[
{
"id": "authors:fjqnr-0yj37",
"collection": "authors",
"collection_id": "fjqnr-0yj37",
"cite_using_url": "https://authors.library.caltech.edu/records/fjqnr-0yj37",
"type": "article",
"title": "Synthesis of bufalin and digitoxigenin derivatives",
"author": [
{
"family_name": "Hubble",
"given_name": "Veronica B.",
"orcid": "0000-0002-1099-8391",
"clpid": "Hubble-Veronica-B"
},
{
"family_name": "Suarez",
"given_name": "Camila A.",
"orcid": "0000-0003-1858-000X",
"clpid": "Suarez-Camila-A"
},
{
"family_name": "Navaratne",
"given_name": "Primali V.",
"orcid": "0000-0002-2679-7199",
"clpid": "Navaratne-Primali-V"
},
{
"family_name": "de la Torre Roehl",
"given_name": "Isabel M.",
"orcid": "0009-0001-4181-1876",
"clpid": "de-la-Torre-Roehl-Isabel"
},
{
"family_name": "Fonteh",
"given_name": "Alfred N.",
"orcid": "0000-0003-4860-5749"
},
{
"family_name": "Harrington",
"given_name": "Michael G."
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "\n
\n
We report the syntheses of seven novel bufalin derivatives and four digitoxigenin derivatives, inspired by the high affinity of bufalin and digitoxigenin to a ubiquitous enzyme called the Na+, K+–ATPase and their biological potential as brain Na+, K+–ATPase modulators. We sought to design and synthesize derivatives that more closely obey CNS-penetrant guidelines set forth by the medicinal chemistry community compared to their natural product class counterparts, by reducing the number of hydrogen bond donors or acceptors and increasing lipophilicity. In addition, we highlight the necessity of a C14 bulky protecting group in the steroid core to set a desired C17-β stereocenter for the synthesis of C17-β-pyridines or pyridones.
\n
\n
Alzheimer neurodegenerative disease (AD) has had a major impact worldwide, with no effective drugs for treatment. We discovered and reported earlier that neurotrophic factor-α1 (NF-α1)/carboxypeptidase E (CPE) reversed neurodegeneration and cognitive dysfunction in AD mouse models. We then predicted computationally and validated experimentally that CPE interacts with a pharmacophore of six residues on the 5-HT1E receptor (HTR1E) to activate the ERK-BCL2 signaling pathway leading to protection of human neurons against oxidative stress–induced cell death. We now report using this pharmacophore for in silico virtual screening of ~6 million small molecules to discover candidates with similar binding and neuroprotective properties as CPE. This in silico search identified a molecule (Z124) that was verified experimentally to bind to HTR1E with protective efficacy comparable to NF-α1/CPE but requiring a higher concentration. Next, we carried out R-group design optimization based on Z124 to identify 4 compounds predicted to have much better efficacy than Z124. These compounds were synthesized and tested for neuroprotective activity. All four compounds showed binding to HTLA-HTR1E cells comparable to CPE. We determined the Kd for two of these compounds: R9, 1.38 ± 0.2 nM, and R10, 2.1 ± 0.2 nM, to be over 15 times better than CPE. Furthermore, all four new compounds showed protective activity against oxidative stress–induced cytotoxicity in human HEK293 cells stably transfected with HTR1E, as well as human primary neurons. Mechanistically, R9 and R10 activated ERK phosphorylation and increased the mitochondria prosurvival protein, BCL2, making them excellent candidates for further development as a drug to treat neurodegenerative diseases.
",
"doi": "10.1073/pnas.2505359122",
"pmcid": "PMC12625973",
"issn": "0027-8424",
"publisher": "National Academy of Sciences",
"publication": "Proceedings of the National Academy of Sciences",
"publication_date": "2025-11-11",
"series_number": "45",
"volume": "122",
"issue": "45",
"pages": "e2505359122"
},
{
"id": "authors:f07nd-jtw22",
"collection": "authors",
"collection_id": "f07nd-jtw22",
"cite_using_url": "https://authors.library.caltech.edu/records/f07nd-jtw22",
"type": "article",
"title": "Formation of vicinal secondary and all-carbon quaternary stereocenters in enantioenriched diazenes via branched-selective Pd-catalyzed allylic alkylation",
"author": [
{
"family_name": "Zoll",
"given_name": "Adam J.",
"clpid": "Zoll-Adam-J"
},
{
"family_name": "Cerione",
"given_name": "Chloe S.",
"clpid": "Cerione-Chloe-S"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The synthesis of enantioenriched alkyl diazenes with vicinal secondary and all\u2011carbon quaternary stereocenters via palladium-catalyzed allylic alkylation is reported. Diazenes were formed in high diastereoselectivity and modest enantioselectivity. Notably, the ratio of branched to linear products was very high, a rarely observed phenomenon in palladium catalysis. The utility of this approach was demonstrated by cleaving the NN bond to form an α-secondary amine with a vicinal all\u2011carbon quaternary stereocenter.
",
"doi": "10.1016/j.tetlet.2025.155657",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2025-07-30",
"volume": "165-166",
"pages": "155657"
},
{
"id": "authors:e0d36-hwr50",
"collection": "authors",
"collection_id": "e0d36-hwr50",
"cite_using_url": "https://authors.library.caltech.edu/records/e0d36-hwr50",
"type": "article",
"title": "Enantioselective Michael Spirocyclization of Palladium Enolates",
"author": [
{
"family_name": "Strong",
"given_name": "Christian Santiago",
"orcid": "0000-0003-1349-302X",
"clpid": "Strong-Christian-Santiago"
},
{
"family_name": "Chen",
"given_name": "Peng-Jui",
"orcid": "0000-0002-3594-0081",
"clpid": "Chen-Peng-Jui"
},
{
"family_name": "Bissenali",
"given_name": "Sanzhar",
"orcid": "0009-0009-2568-393X",
"clpid": "Bissenali-Sanzhar"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report an enantioselective and diastereoselective Michael spirocyclization reaction of tetrasubstituted palladium enolates. This allows for the formation of adjacent all-carbon quaternary and tertiary stereocenters in good yield, dr, and ee. Various subsequent cyclization reactions enable access to a diverse range of tricyclic scaffolds. The mechanism of this transformation and the origins of stereoselectivity are investigated via quantum mechanics calculations.",
"doi": "10.1021/acscatal.5c02758",
"issn": "2155-5435",
"publisher": "American Chemical Society",
"publication": "ACS Catalysis",
"publication_date": "2025-07-18",
"series_number": "14",
"volume": "15",
"issue": "14",
"pages": "12231-12237"
},
{
"id": "authors:fg309-75g82",
"collection": "authors",
"collection_id": "fg309-75g82",
"cite_using_url": "https://authors.library.caltech.edu/records/fg309-75g82",
"type": "article",
"title": "On the unexpected formation of [2.2.1]- and [2.1.1]homotriblattanes",
"author": [
{
"family_name": "Samkian",
"given_name": "Adrian E.",
"orcid": "0000-0002-0068-3572",
"clpid": "Samkian-Adrian-E"
},
{
"family_name": "Nguyen",
"given_name": "Hanh T."
},
{
"family_name": "Vanderwal",
"given_name": "Christopher D.",
"orcid": "0000-0001-7218-4521"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A new class of polycyclic caged compounds, the [2.n.1]homotriblattanes, is described herein. These scaffolds are accessed through a concise, three-step sequence featuring an unexpected radical cyclization of a-bromocyclopropyl ketones. Their structures and stereochemical assignments were confirmed by a combination of 2D NMR and X-ray crystallography. DFT studies provide mechanistic insight into their formation and the side products formed en route. This study expands the known chemical space of polycyclic cages and offers a new entry point into highly complex 3- dimensional frameworks.
",
"doi": "10.1016/j.tetlet.2025.155591",
"pmcid": "PMC12121957",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2025-07-15",
"volume": "164",
"pages": "155591"
},
{
"id": "authors:gs070-khc69",
"collection": "authors",
"collection_id": "gs070-khc69",
"cite_using_url": "https://authors.library.caltech.edu/records/gs070-khc69",
"type": "article",
"title": "Asymmetric Total Synthesis of (\u2212)-Crotonine G and (\u2212)-Crotonolide D",
"author": [
{
"family_name": "Yu",
"given_name": "Hao",
"orcid": "0009-0008-6002-6276",
"clpid": "Yu-Hao"
},
{
"family_name": "Hatano",
"given_name": "Yutaro",
"clpid": "Hatano-Yutaro"
},
{
"family_name": "Chen",
"given_name": "Peng-Jui",
"orcid": "0000-0002-3594-0081",
"clpid": "Chen-Peng-Jui"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective total syntheses of crotonine G and crotonolide D are disclosed. The synthetic approach employs a SmI2 mediated ketyl radical cyclization to form the highly congested quaternary carbon at the center of these complex molecules. Following the furan introduction, the core structure of the natural product is constructed via oxidative olefin cleavage to install the unusual C-19 and C-20 oxidation. Finally, palladium-catalyzed carbonylation, furan oxidation and acid mediated condensation/epimerization complete the synthesis.
",
"doi": "10.1021/jacs.5c07585",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2025-07-02",
"series_number": "26",
"volume": "147",
"issue": "26",
"pages": "22358-22362"
},
{
"id": "authors:rcty6-hkz15",
"collection": "authors",
"collection_id": "rcty6-hkz15",
"cite_using_url": "https://authors.library.caltech.edu/records/rcty6-hkz15",
"type": "article",
"title": "Concise Syntheses of Lycojapomine Alkaloids Enabled by Radical Dearomatization of a Pyrrole",
"author": [
{
"family_name": "Gross",
"given_name": "Benjamin M.",
"orcid": "0000-0002-9124-2317",
"clpid": "Gross-Benjamin-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We disclose the first total syntheses of the complex alkaloids Lycojapomine A and B. Our synthetic strategy is built on a dearomatization and stepwise functionalization of a pyrrole starting material, constructing the three-dimensional structure of the target around it. This is enabled by a high-yielding photoinduced primary radical addition from the N-hydroxy phthalimide ester and a subsequent silver-catalyzed 5-endo-dig and Aza-silyl-Prins annulation cascade. Divergent control over an aldol reaction yields both Lycojapomines A and B in an efficient manner, without the need for any excess protecting groups.
",
"doi": "10.1021/jacs.5c05721",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2025-06-18",
"series_number": "24",
"volume": "147",
"issue": "24",
"pages": "20200-20204"
},
{
"id": "authors:vvhcm-ykk10",
"collection": "authors",
"collection_id": "vvhcm-ykk10",
"cite_using_url": "https://authors.library.caltech.edu/records/vvhcm-ykk10",
"type": "article",
"title": "Potassium tert-butoxide mediated stereoselective/direct Mannich reaction of \u03b1-substituted-\u03b3-lactams with in situ generated aryl N-silyl imines",
"author": [
{
"family_name": "Casselman",
"given_name": "Tyler D.",
"clpid": "Casselman-Tyler-D"
},
{
"family_name": "Madhusudhanan",
"given_name": "Mithun C.",
"orcid": "0000-0002-3122-0802"
},
{
"family_name": "Mai",
"given_name": "Binh Khanh",
"orcid": "0000-0001-8487-1417"
},
{
"family_name": "Liu",
"given_name": "Peng",
"orcid": "0000-0002-8188-632X"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A potassium tert-butoxide (KOt-Bu)-mediated Mannich reaction between α-substituted-γ-lactams and N-silyl imines is reported. N-silyl imines are generated in situ from readily available aryl nitriles and directly combined with the lactams, without preformation of the lactam enolate, to afford the α-quaternary center-bearing Mannich bases in high yield and with high diastereoselectivity (24 examples). This reaction is shown to be catalytic with respect to KOt-Bu and the catalytic mechanism has been investigated using density functional theory calculations. The computational investigations suggest that the diastereoselectivity is controlled by explicit interactions between a binuclear potassium complex and both the imine nitrogen and the enolate oxygen atoms in the selectivity-determining transition states. The Mannich products are shown to be useful in accessing novel spirocyclic pyrrolidines.
",
"doi": "10.1039/d4sc06391k",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2025-06-14",
"series_number": "22",
"volume": "16",
"issue": "22",
"pages": "9863-9871"
},
{
"id": "authors:e14xd-gsb05",
"collection": "authors",
"collection_id": "e14xd-gsb05",
"cite_using_url": "https://authors.library.caltech.edu/records/e14xd-gsb05",
"type": "article",
"title": "A Modular Cyclopentene Annulation",
"author": [
{
"family_name": "Samkian",
"given_name": "Adrian E.",
"orcid": "0000-0002-0068-3572",
"clpid": "Samkian-Adrian-E"
},
{
"family_name": "Poonswat",
"given_name": "Kasam",
"clpid": "Poonswat-Kasam"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report a modular three-component annulation among propargyl zinc reagents, unsaturated 1,3-dicarbonyls, and electrophiles to enable rapid construction of highly substituted cyclopentenes. In addition to optimization studies, a range of substrates were investigated. These products can be readily diversified to highlight their synthetic utility.
",
"doi": "10.1021/acs.orglett.5c01750",
"pmcid": "PMC12251832",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2025-06-06",
"series_number": "22",
"volume": "27",
"issue": "22",
"pages": "5876-5879"
},
{
"id": "authors:qzkff-b8n97",
"collection": "authors",
"collection_id": "qzkff-b8n97",
"cite_using_url": "https://authors.library.caltech.edu/records/qzkff-b8n97",
"type": "article",
"title": "Direct, Convergent \u03b1-Amidation of \u03b2-Keto Esters via Nickelocene Catalysis",
"author": [
{
"family_name": "Sharp",
"given_name": "Kimberly R.",
"orcid": "0000-0002-5718-3552",
"clpid": "Sharp-Kimberly-R"
},
{
"family_name": "Siddiqui",
"given_name": "Sara Y.",
"clpid": "Siddiqui-Sara-Y"
},
{
"family_name": "Nikas",
"given_name": "Emily G.",
"orcid": "0000-0003-0455-605X",
"clpid": "Nikas-Emily-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "\u03b1-Amidation of carbonyl-containing compounds without prefunctionalization of starting materials represents a continuing challenge within the scientific community. Here, nickelocene is used catalytically to effect an amidation of \u03b2-keto esters. Broad substrate tolerance on both coupling partners is achieved, enabling the application toward a convergent synthetic strategy. Initial mechanistic investigations suggest complex activation pathways.",
"doi": "10.1021/acs.orglett.5c01621",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2025-06-05"
},
{
"id": "authors:tsen5-0ka95",
"collection": "authors",
"collection_id": "tsen5-0ka95",
"cite_using_url": "https://authors.library.caltech.edu/records/tsen5-0ka95",
"type": "article",
"title": "Synthesis of the Pentacyclic Core of Sanguinone B Enabled by Alkyne Functionalization",
"author": [
{
"family_name": "Farhi",
"given_name": "Jonathan",
"clpid": "Farhi-Jonathan"
},
{
"family_name": "Rezgui",
"given_name": "Samir P.",
"orcid": "0000-0003-4080-9835",
"clpid": "Rezgui-Samir-P"
},
{
"family_name": "Yu",
"given_name": "Hao",
"orcid": "0009-0008-6002-6276",
"clpid": "Yu-Hao"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Sanguinones A and B are recently isolated pyrroloiminoquinone alkaloids possessing a rare C4 carboxylic acid. We report a synthetic approach toward the full carbon and nitrogen pentacyclic core of sanguinone B, with the correct oxidation at C4. Highlights of this approach include the application of a Larock/Buchwald-Hartwig annulation cascade to access a key tricyclic intermediate and alkyne functionalization using Rh(I) or Cu(I) catalysis to access hindered benzylic ketones.
",
"doi": "10.1021/acs.orglett.5c01332",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2025-05-30",
"series_number": "21",
"volume": "27",
"issue": "21",
"pages": "5390-5393"
},
{
"id": "authors:gtrx1-ayw31",
"collection": "authors",
"collection_id": "gtrx1-ayw31",
"cite_using_url": "https://authors.library.caltech.edu/records/gtrx1-ayw31",
"type": "monograph",
"title": "Asymmetric Total Synthesis of (\u2013)-Crotonine G and (\u2013)-Crotonolide D",
"author": [
{
"family_name": "Yu",
"given_name": "Hao",
"clpid": "Yu-Hao"
},
{
"family_name": "Hatano",
"given_name": "Yutaro",
"clpid": "Hatano-Yutaro"
},
{
"family_name": "Chen",
"given_name": "Peng\u2013Jui",
"clpid": "Chen-Peng\u2013Jui"
},
{
"family_name": "Virgil",
"given_name": "Scott",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective total syntheses of crotonine G and crotonolide D are disclosed. The synthetic approach employs a SmI2 mediated ketyl radical cyclization to form the highly congested quaternary carbon at the center of these complex molecules. Following the furan introduction, the core structure of the natural product is con-structed via oxidative olefin cleavage to install the unusual C-19 and C-20 oxidation. Finally, palladium catalyzed carbonylation, furan oxidation and acid mediated condensation/epimerization completes the synthesis.",
"doi": "10.26434/chemrxiv-2025-zh07z",
"publisher": "American Chemical Society (ACS)",
"publication_date": "2025-05-08"
},
{
"id": "authors:5twmy-cbv13",
"collection": "authors",
"collection_id": "5twmy-cbv13",
"cite_using_url": "https://authors.library.caltech.edu/records/5twmy-cbv13",
"type": "monograph",
"title": "Enantioselective Michael Spirocyclization of Palladium Enolates",
"author": [
{
"family_name": "Strong",
"given_name": "Christian S.",
"orcid": "0000-0003-1349-302X",
"clpid": "Strong-Christian-S"
},
{
"family_name": "Chen",
"given_name": "Peng-Jui",
"clpid": "Chen-Peng-Jui"
},
{
"family_name": "Bissenali",
"given_name": "Sanzhar",
"orcid": "0009-0009-2568-393X",
"clpid": "Bissenali-Sanzhar"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report an enantio- and diastereoselective Michael spirocyclization reaction of tetrasubstituted palladium enolates. This allows for the formation of adjacent all-carbon quaternary and tertiary stereocenters in good yield, dr, and ee. Various subsequent cyclization reactions enable access to a diverse range of tricyclic scaffolds. The mechanism of this trans-formation is evaluated via quantum mechanics calculations to elucidate the origins of stereoselectivity and the mechanism of catalyst turnover.
",
"doi": "10.26434/chemrxiv-2025-59lfh",
"publisher": "ChemRxiv",
"publication_date": "2025-03-07"
},
{
"id": "authors:h0tea-jnr76",
"collection": "authors",
"collection_id": "h0tea-jnr76",
"cite_using_url": "https://authors.library.caltech.edu/records/h0tea-jnr76",
"type": "publication_workingpaper",
"title": "Mo-Catalyzed Asymmetric Allylic Alkylation Enabling the Con-struction of Highly Enantioenriched 1,4-Dicarbonyl Scaffolds",
"author": [
{
"family_name": "Moghadam",
"given_name": "Farbod A.",
"orcid": "0009-0005-4442-2349",
"clpid": "Moghadam-Farbod-A"
},
{
"family_name": "Cerione",
"given_name": "Chloe S.",
"clpid": "Cerione-Chloe-S"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein, we report a Mo-catalyzed allylic alkylation that couples malonate nucleophiles with linear, tri-substituted allylic electrophiles, followed by a rapid ozonolysis. The process delivers 1,4-dicarbonyl compounds con-taining an -quaternary aldehyde motif with excellent enantioselectivity. This constitutes the first example of a Mo-catalyzed asymmetric allylic alkylation to form an electrophile-derived all-carbon quaternary stereocenter. The reac-tivity and stereoselectivity of the process was enabled by the invention of ShabyDACH, a novel C1-symmetric diamino-cyclohexane (DACH) pyridyl ligand. The utility of this transformation was demonstrated through a series of diverse synthetic transformations.
",
"doi": "10.26434/chemrxiv-2025-41644",
"publisher": "ChemRxiv",
"publication_date": "2025-03-06"
},
{
"id": "authors:psyqa-12z51",
"collection": "authors",
"collection_id": "psyqa-12z51",
"cite_using_url": "https://authors.library.caltech.edu/records/psyqa-12z51",
"type": "article",
"title": "Formation of All-Carbon Quaternary Centers via Enantioselective Pd-Catalyzed \u03b1-Vinylation of \u03b3-Lactams",
"author": [
{
"family_name": "Moghadam",
"given_name": "Farbod A."
},
{
"family_name": "Barbor",
"given_name": "Jay P.",
"orcid": "0000-0003-2787-4923"
},
{
"family_name": "Chan",
"given_name": "Melinda",
"orcid": "0000-0002-2495-0110"
},
{
"family_name": "Jette",
"given_name": "Carina"
},
{
"family_name": "Sakurai",
"given_name": "Shunya"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein, we report an enantioselective vinylation of α-substituted γ-lactams that forges quaternary centers in up to 59% yield with 94% ee. The use of canonically inactive vinyl chloride electrophiles afforded the highest yields and levels of stereoselectivity, and a range of trisubstituted vinyl chlorides were found to be proficient in promoting this transformation. These stereogenic products could be further elaborated to functionally rich scaffolds, thereby highlighting the synthetic utility of this process.
",
"doi": "10.1021/acs.orglett.4c02551",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2024-09-13",
"series_number": "36",
"volume": "26",
"issue": "36",
"pages": "7551\u20137554"
},
{
"id": "authors:s5m1v-aa475",
"collection": "authors",
"collection_id": "s5m1v-aa475",
"cite_using_url": "https://authors.library.caltech.edu/records/s5m1v-aa475",
"type": "article",
"title": "Enantioselective Nickel-Catalyzed \u03b1-Spirocyclization of Lactones",
"author": [
{
"family_name": "Stanko",
"given_name": "Allison M.",
"orcid": "0000-0003-0576-3739",
"clpid": "Stanko-Allison-M"
},
{
"family_name": "Ramirez",
"given_name": "Melissa",
"clpid": "Ramirez-Melissa"
},
{
"family_name": "de Almenara",
"given_name": "Adrian J.",
"clpid": "de-Almenara-Adrian-J"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein we report a strategy for the enantioselective synthesis of spirocycles containing all-carbon quaternary centers via nickel-catalyzed intramolecular addition of lactone enolates to aryl nitriles. The established lactone α-spirocyclization efficiently and enantioselectively forges 5-, 6-, and 7-membered rings, performing best in the synthesis of 7-membered rings (up to 90% ee). This discovery represents an expansion of the synthetic toolkit for enantioselective spirocyclization, providing access to chiral, pharmaceutically relevant spirocyclic products.
",
"doi": "10.1021/acs.orglett.4c01661",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2024-08-16",
"series_number": "32",
"volume": "26",
"issue": "32",
"pages": "6793-6797"
},
{
"id": "authors:nv5k6-kd788",
"collection": "authors",
"collection_id": "nv5k6-kd788",
"cite_using_url": "https://authors.library.caltech.edu/records/nv5k6-kd788",
"type": "article",
"title": "Total Synthesis of Hypersampsone M",
"author": [
{
"family_name": "Samkian",
"given_name": "Adrian E.",
"orcid": "0000-0002-0068-3572",
"clpid": "Samkian-Adrian-E"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "\n
We report the first total synthesis of hypersampsone M, an archetypal member of the homoadamantane polycyclic polyprenylated acylphloroglucinols (PPAPs). Commencing from cyclohexenone, a key cyclopentene annulation followed by ring-expansion results in an elusive hydrazulene that undergoes a series of unexpected late-stage transformations, ultimately enabling completion of the synthesis. The route detailed herein represents a potentially general strategy for the synthesis of related homoadamantane PPAPs.
\n
The bis-tetrahydroisoquinoline (bis-THIQ) natural products represent a medicinally important class of isoquinoline alkaloids that exhibit broad biological activities with particularly potent antitumor properties, as exemplified by the two U.S. FDA approved molecules trabectidin and lurbinectedin. Accordingly, other members within the bis-THIQ family have emerged as prime targets for synthetic chemists, aiming to innovate an orthogonal chemical production of these compounds. With the ability of these complementary strategies to reliably and predictably manipulate molecular structures with atomic precision, this should allow the preparation of synthetic derivatives not existing in nature as new drug leads in the development of novel medicines with desired biological functions.
\nBeyond the biological perspective, bis-THIQ natural products also possess intricate and unique structures, serving as a source of intellectual stimulation for synthetic organic chemists. Within our laboratory, we have developed an integrated program that combines reaction development and target-directed synthesis, leveraging the architecturally complex molecular framework of bis-THIQ natural products as a driving force for the advancement of novel reaction methodologies. In this Account, we unveil our synthetic efforts in a comprehensive story, describing how our synthetic strategy toward bis-THIQ natural products, specifically jorunnamycin A and jorumycin, has evolved over the course of our studies through our key transformations comprising (a) the direct functionalization of isoquinoline N-oxide to prepare the bis-isoquinoline (bis-IQ) intermediate, (b) the diastereoselective and enantioselective isoquinoline hydrogenation to forge the pentacyclic skeleton of the natural product, and (c) the late-stage oxygenation chemistry to adjust the oxidation states of the A- and E-rings. First, we detail our plan in utilizing the aryne annulation strategy to prepare isoquinoline fragments for the bis-THIQ molecules. Faced with unpromising results in the direct C–H functionalization of isoquinoline N-oxide, we lay out in this Account our rationale behind the design of each isoquinoline coupling partner to overcome these challenges. Additionally, we reveal the inspiration for our hydrogenation system, the setup of our pseudo-high-throughput screening, and the extension of the developed hydrogenation protocols to other simplified isoquinolines.
\nIn the context of non-natural bis-THIQ molecules, we have successfully adapted this tandem coupling/hydrogenation approach in the preparation of perfluorinated bis-THIQs, representing the first set of electron-deficient non-natural analogues. Finally, we include our unsuccessful late-stage oxygenation attempts prior to the discovery of the Pd-catalyzed C–O cross-coupling reaction. With this full disclosure of the chemistry developed for the syntheses of bis-THIQs, we hope our orthogonal synthetic tactics will provide useful information and serve as an inspiration for the future development of bis-THIQ pharmaceuticals.
",
"doi": "10.1021/acs.accounts.4c00262",
"pmcid": "PMC11223266",
"issn": "0001-4842",
"publisher": "American Chemical Society",
"publication": "Accounts of Chemical Research",
"publication_date": "2024-07-02",
"series_number": "13",
"volume": "57",
"issue": "13",
"pages": "1870-1884"
},
{
"id": "authors:53ycg-4c740",
"collection": "authors",
"collection_id": "53ycg-4c740",
"cite_using_url": "https://authors.library.caltech.edu/records/53ycg-4c740",
"type": "article",
"title": "Strategies for the Development of Asymmetric and Non\u2010Directed Petasis Reactions",
"author": [
{
"family_name": "Gonzalez",
"given_name": "Kevin J.",
"clpid": "Gonzalez-Kevin-J"
},
{
"family_name": "Cerione",
"given_name": "Chloe",
"clpid": "Cerione-Chloe"
},
{
"family_name": "Stoltz",
"given_name": "Brian",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "\n
\n
\n\n\n
\n
The Petasis reaction is a multicomponent reaction of aldehydes, amines and organoboron reagents and is a useful method for the construction of substituted amines. Despite the significant advancement of the Petasis reaction since its invention in 1993, strategies for asymmetric and non-directed Petasis reactions remain limited. To date, there are very few catalytic asymmetric Petasis reactions and almost all asymmetric reports employ a chiral auxiliary. Likewise, the aldehyde component often requires a directing group, ultimately limiting the reaction’s scope. In this concept, key methods for asymmetric and non-directed Petasis reactions are discussed, focusing on how these conceptual advances can be applied to solve long-standing gaps in the Petasis literature.
\n
\n\n
\n
\n
\n
We report quantum mechanics calculations and quasiclassical trajectory simulations of [4 + 2] reactions using three common dienolate substrates: siloxy dienes, Li dienolates, and conjugated Pd enolates. Asynchronous transition structures and unequal bond formation were invariably found, with average time gaps of developing bonds ranging from 26.5 to >251.0 fs. The results display a spectrum of dynamically concerted and stepwise [4 + 2] reactions, offering insights into the origin of the stereochemical outcomes of such reactions.
\n
The norcembranoid and cembranoid diterpenoids represent an intriguing class of natural products isolated from marine sources. Their chemical synthesis has been a challenging and exciting field of research over the past two decades, owing largely to their structural complexity. We recently disclosed a total synthesis of a member of this class, ineleganolide, in a 23 step longest linear sequence. In search of a shorter, more efficient route, we have devised a new strategy for the synthesis of a key bicyclic enone. Disclosed herein is our improved synthesis of this strained intermediate, completing the formal synthesis of ineleganolide in only 14 steps, thereby shortening our previous synthesis by 9 steps.
",
"doi": "10.1016/j.tetlet.2024.155011",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2024-04-28",
"volume": "140",
"pages": "155011"
},
{
"id": "authors:dhwpw-c6z37",
"collection": "authors",
"collection_id": "dhwpw-c6z37",
"cite_using_url": "https://authors.library.caltech.edu/records/dhwpw-c6z37",
"type": "article",
"title": "Enantioselective Total Synthesis of (\u2212)-Hunterine A Enabled by a Desymmetrization/Rearrangement Strategy",
"author": [
{
"family_name": "Hicks",
"given_name": "Elliot F.",
"clpid": "Hicks-Elliot-F"
},
{
"family_name": "Inoue",
"given_name": "Kengo",
"clpid": "Inoue-Kengo"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective total synthesis of (−)-hunterine A is disclosed. Our strategy employs a catalytic asymmetric desymmetrization of a symmetrical diketone and subsequent Beckmann rearrangement to construct a 5,6-α-aminoketone. A convergent 1,2-addition joins a vinyl dianion nucleophile and the enantioenriched ketone. The endgame of the synthesis features an aza-Cope/Mannich reaction and azide-olefin dipolar cycloaddition to complete the pentacyclic ring system. The synthesis is completed through a regioselective aziridine ring opening.
",
"doi": "10.1021/jacs.3c13590",
"pmcid": "PMC10885145",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2024-02-21",
"series_number": "7",
"volume": "146",
"issue": "7",
"pages": "4340-4345"
},
{
"id": "authors:pec2g-df866",
"collection": "authors",
"collection_id": "pec2g-df866",
"cite_using_url": "https://authors.library.caltech.edu/records/pec2g-df866",
"type": "article",
"title": "Low Part-Per-Trillion, Humidity Resistant Detection of Nitric Oxide Using Microtoroid Optical Resonators",
"author": [
{
"family_name": "Xu",
"given_name": "Yinchao",
"clpid": "Xu-Yinchao"
},
{
"family_name": "Stanko",
"given_name": "Allison M.",
"orcid": "0000-0003-0576-3739",
"clpid": "Stanko-Allison-M"
},
{
"family_name": "Cerione",
"given_name": "Chloe S.",
"clpid": "Cerione-Chloe-S"
},
{
"family_name": "Lohrey",
"given_name": "Trevor D.",
"clpid": "Lohrey-Trevor-D"
},
{
"family_name": "McLeod",
"given_name": "Euan",
"orcid": "0000-0002-6327-3642",
"clpid": "Su-Judith"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "\n
The nitric oxide radical plays pivotal roles in physiological as well as atmospheric contexts. Although the detection of dissolved nitric oxide in vivo has been widely explored, highly sensitive (i.e., low part-per-trillion level), selective, and humidity-resistant detection of gaseous nitric oxide in air remains challenging. In the field, humidity can have dramatic effects on the accuracy and selectivity of gas sensors, confounding data, and leading to overestimation of gas concentration. Highly selective and humidity-resistant gaseous NO sensors based on laser-induced graphene were recently reported, displaying a limit of detection (LOD) of 8.3 ppb. Although highly sensitive (LOD = 590 ppq) single-wall carbon nanotube NO sensors have been reported, these sensors lack selectivity and humidity resistance. In this report, we disclose a highly sensitive (LOD = 2.34 ppt), selective, and humidity-resistant nitric oxide sensor based on a whispering-gallery mode microtoroid optical resonator. Excellent analyte selectivity was enabled via novel ferrocene-containing polymeric coatings synthesized via reversible addition–fragmentation chain-transfer polymerization. Utilizing a frequency locked optical whispering evanescent resonator system, the microtoroid’s real-time resonance frequency shift response to nitric oxide was tracked with subfemtometer resolution. The lowest concentration experimentally detected was 6.4 ppt, which is the lowest reported to date. Additionally, the performance of the sensor remained consistent across different humidity environments. Lastly, the impact of the chemical composition and molecular weight of the novel ferrocene-containing polymeric coatings on sensing performance was evaluated. We anticipate that our results will have impact on a wide variety of fields where NO sensing is important such as medical diagnostics through exhaled breath, determination of planetary habitability, climate change, air quality monitoring, and treating cardiovascular and neurological disorders.
\n
Aleutianamine is a recently isolated pyrroloiminoquinone natural product that displays potent and selective biological activity toward human pancreatic cancer cells with an IC\u2085\u2080 of 25 nM against PANC-1, making it a potential candidate for therapeutic development. We report a synthetic approach to aleutianamine wherein the unique [3.3.1] ring system and tertiary sulfide of this alkaloid were constructed via a novel palladium-catalyzed dearomative thiophene functionalization. Other highlights of the synthesis include a palladium-catalyzed decarboxylative pinacol-type rearrangement of an allylic carbonate to install a ketone and a late-stage oxidative amination. This concise and convergent strategy will enable access to analogues of aleutianamine and further investigation of the biological activity of this unique natural product.
",
"doi": "10.1021/jacs.3c10212",
"pmcid": "PMC10690800",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-11-29",
"series_number": "47",
"volume": "145",
"issue": "47",
"pages": "25533-25537"
},
{
"id": "authors:k5ygt-7pr51",
"collection": "authors",
"collection_id": "k5ygt-7pr51",
"cite_using_url": "https://authors.library.caltech.edu/records/k5ygt-7pr51",
"type": "article",
"title": "Particle-phase accretion forms dimer esters in pinene secondary organic aerosol",
"author": [
{
"family_name": "Kenseth",
"given_name": "Christopher M.",
"orcid": "0000-0003-3188-2336",
"clpid": "Kenseth-Christopher-M"
},
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Rezgui",
"given_name": "Samir P.",
"orcid": "0000-0003-4080-9835",
"clpid": "Rezgui-Samir-P"
},
{
"family_name": "Chen",
"given_name": "Jing",
"orcid": "0000-0001-6545-6197"
},
{
"family_name": "Huang",
"given_name": "Yuanlong",
"orcid": "0000-0002-6726-8904",
"clpid": "Huang-Yuanlong"
},
{
"family_name": "Dalleska",
"given_name": "Nathan F.",
"orcid": "0000-0002-2059-1587",
"clpid": "Dalleska-Nathan-F"
},
{
"family_name": "Kjaergaard",
"given_name": "Henrik G.",
"orcid": "0000-0002-7275-8297"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Seinfeld",
"given_name": "John H.",
"orcid": "0000-0003-1344-4068",
"clpid": "Seinfeld-J-H"
},
{
"family_name": "Wennberg",
"given_name": "Paul O.",
"orcid": "0000-0002-6126-3854",
"clpid": "Wennberg-P-O"
}
],
"abstract": "Secondary organic aerosol (SOA) is ubiquitous in the atmosphere and plays a pivotal role in climate, air quality, and health. The production of low-volatility dimeric compounds through accretion reactions is a key aspect of SOA formation. However, despite extensive study, the structures and thus the formation mechanisms of dimers in SOA remain largely uncharacterized. In this work, we elucidate the structures of several major dimer esters in SOA from ozonolysis of \u03b1-pinene and \u03b2-pinene\u2014substantial global SOA sources\u2014through independent synthesis of authentic standards. We show that these dimer esters are formed in the particle phase and propose a mechanism of nucleophilic addition of alcohols to a cyclic acylperoxyhemiacetal. This chemistry likely represents a general pathway to dimeric compounds in ambient SOA.",
"doi": "10.1126/science.adi0857",
"issn": "0036-8075",
"publisher": "American Association for the Advancement of Science",
"publication": "Science",
"publication_date": "2023-11-17",
"series_number": "6672",
"volume": "382",
"issue": "6672",
"pages": "787-792"
},
{
"id": "authors:mb8sx-eck72",
"collection": "authors",
"collection_id": "mb8sx-eck72",
"cite_using_url": "https://authors.library.caltech.edu/records/mb8sx-eck72",
"type": "article",
"title": "Editorial for special issue in honor of Professor John Wood",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "It is with great enthusiasm that we publish this special issue of Tetrahedron and Tetrahedron Letters in honor of John L. Wood, the Robert A. Welch Distinguished Professor of Chemistry at Baylor University. John served as a long-time Associate Editor for the Americas of Tetrahedron Letters and performed these duties for twenty years from 2001 to 2021 with the highest possible ethical and scientific standards. Wood is among a small group of truly gifted leaders in the field of organic chemistry and one of the most scholarly, selfless, and committed citizens of our community.
",
"doi": "10.1016/j.tet.2023.133700",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2023-11-16",
"volume": "148",
"pages": "133700"
},
{
"id": "authors:xtx2s-t7e87",
"collection": "authors",
"collection_id": "xtx2s-t7e87",
"cite_using_url": "https://authors.library.caltech.edu/records/xtx2s-t7e87",
"type": "article",
"title": "Enantioselective 1,3-Dipolar Cycloadditions of \u03b1-Methylene Lactams to Construct Spirocycles",
"author": [
{
"family_name": "Nishiura",
"given_name": "Yuji",
"orcid": "0000-0001-8860-4666",
"clpid": "Nishiura-Yuji"
},
{
"family_name": "Gonzalez",
"given_name": "Kevin J.",
"orcid": "0000-0002-4904-590X",
"clpid": "Gonzalez-Kevin-J"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Spirocyclic scaffolds are important motifs due to their potential to bestow favorable effects on pharmaceutical compounds. However, there is a need for efficient methods for their enantioselective construction. We report a method for the asymmetric 1,3-dipolar cycloaddition of diazoacetates or nitrile oxides with \u03b1-methylene lactams to prepare chiral spirocyclic heterocycles. The methodology is high yielding (up to 91% yield) and enantioselective (up to 89% ee) for a wide range of N-substituents and 6- and 7-membered ring lactam substrates.
",
"doi": "10.1021/acs.orglett.3c01978",
"pmcid": "PMC10496134",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2023-09-08",
"series_number": "35",
"volume": "25",
"issue": "35",
"pages": "6469-6473"
},
{
"id": "authors:8yw7r-nhf53",
"collection": "authors",
"collection_id": "8yw7r-nhf53",
"cite_using_url": "https://authors.library.caltech.edu/records/8yw7r-nhf53",
"type": "article",
"title": "Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to \u03b1,\u03b2-Unsaturated Lactams: Enantioselective Construction of All-Carbon Quaternary Stereocenters in Saturated Nitrogen-Containing Heterocycles",
"author": [
{
"family_name": "Zhang",
"given_name": "Tianyi",
"orcid": "0000-0001-8289-3102",
"clpid": "Zhang-Tianyi"
},
{
"family_name": "Nishiura",
"given_name": "Yuji",
"orcid": "0000-0001-8860-4666",
"clpid": "Nishiura-Yuji"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Stereogenic nitrogen-containing heterocycles are ubiquitous in natural products and pharmaceutical compounds, but methods for their enantioselective construction have remained elusive. We report a general method for the asymmetric conjugate addition of arylboronic acids to \u03b2-alkyl/aryl \u03b1,\u03b2-unsaturated lactams that affords chiral \u03b2,\u03b2-disubstituted lactams. The transformation is operationally simple and air- and moisture-tolerant and uses a commercially available (S)-t-Bu-PyOx ligand. The method is high-yielding (up to 95% yield) and enantioselective (up to 97% ee) for a wide range of arylboronic acids and \u03b1,\u03b2-unsaturated lactams, including those with different ring sizes.
",
"doi": "10.1021/acs.orglett.3c02064",
"pmcid": "PMC10496148",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2023-09-08",
"series_number": "35",
"volume": "25",
"issue": "35",
"pages": "6479-6484"
},
{
"id": "authors:nj0zp-kv080",
"collection": "authors",
"collection_id": "nj0zp-kv080",
"cite_using_url": "https://authors.library.caltech.edu/records/nj0zp-kv080",
"type": "article",
"title": "Origins of Enhanced Enantioselectivity in the Pd-Catalyzed Decarboxylative Allylic Alkylation of N-Benzoyl Lactams",
"author": [
{
"family_name": "Cusumano",
"given_name": "Alexander",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander"
},
{
"family_name": "Zhang",
"given_name": "Tianyi",
"orcid": "0000-0001-8289-3102",
"clpid": "Zhang-Tianyi"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We explore the origins of the marked improvement in enantioselectivity in the inner-sphere (PHOX)Pd-catalyzed allylic alkylation of N-benzoyl lactam nucleophiles over their carbocyclic counterparts. We employ density functional theory calculations to aid in the interpretation of experimental results. Ultimately, we propose that the enhancement in enantioselectivity arises primarily from noncovalent interactions between the substrate and ligand rather than secondary substrate chelation, as previously hypothesized.
",
"doi": "10.3390/catal13091258",
"pmcid": "PMC10662798",
"issn": "2073-4344",
"publisher": "MDPI AG",
"publication": "Catalysts",
"publication_date": "2023-09",
"series_number": "9",
"volume": "13",
"issue": "9",
"pages": "1258"
},
{
"id": "authors:wwtth-30504",
"collection": "authors",
"collection_id": "wwtth-30504",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230718-855947900.3",
"type": "article",
"title": "Recent Advances in the Total Synthesis of the Tetrahydroisoquinoline Alkaloids (2002\u20132020)",
"author": [
{
"family_name": "Kim",
"given_name": "Alexia N.",
"orcid": "0000-0002-4060-8892",
"clpid": "Kim-Alexia-N"
},
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Du",
"given_name": "Emily",
"clpid": "Du-Emily"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The tetrahydroisoquinoline (THIQ) natural products constitute one of the largest families of alkaloids and exhibit a wide range of structural diversity and biological activity. Ranging from simple THIQ natural products to complex trisTHIQ alkaloids such as the ecteinascidins, the chemical syntheses of these alkaloids and their analogs have been thoroughly investigated due to their intricate structural features and functionalities, as well as their high therapeutic potential. This review describes the general structure and biosynthesis of each family of THIQ alkaloids as well as recent advancements of the total synthesis of these natural products from 2002 to 2020. Recent chemical syntheses that have emerged harnessing novel, creative synthetic design, and modern chemical methodology will be highlighted. This review will hopefully serve as a guide for the unique strategies and tools used in the total synthesis of THIQ alkaloids, as well as address the longstanding challenges in their chemical and biosynthesis.",
"doi": "10.1021/acs.chemrev.3c00054",
"pmcid": "PMC10416225",
"issn": "0009-2665",
"publisher": "American Chemical Society",
"publication": "Chemical Reviews",
"publication_date": "2023-08-09",
"series_number": "15",
"volume": "123",
"issue": "15",
"pages": "9447-9496"
},
{
"id": "authors:x70h2-sha78",
"collection": "authors",
"collection_id": "x70h2-sha78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-856879000.13",
"type": "article",
"title": "Development of a Nickel-Catalyzed N\u2013N Coupling for the Synthesis of Hydrazides",
"author": [
{
"family_name": "Barbor",
"given_name": "Jay P.",
"clpid": "Barbor-Jay-P"
},
{
"family_name": "Nair",
"given_name": "Vaishnavi N.",
"orcid": "0000-0002-2873-0596",
"clpid": "Nair-Vaishnavi-N"
},
{
"family_name": "Sharp",
"given_name": "Kimberly R.",
"clpid": "Sharp-Kimberly-R"
},
{
"family_name": "Lohrey",
"given_name": "Trevor D.",
"orcid": "0000-0003-3568-7861",
"clpid": "Lohrey-Trevor-D"
},
{
"family_name": "Dibrell",
"given_name": "Sara E.",
"orcid": "0000-0003-0332-1101",
"clpid": "Dibrell-Sara-E"
},
{
"family_name": "Shah",
"given_name": "Tejas K.",
"orcid": "0000-0002-2345-4764",
"clpid": "Shah-Tejas-K"
},
{
"family_name": "Walsh",
"given_name": "Martin J.",
"clpid": "Walsh-Martin-J"
},
{
"family_name": "Reisman",
"given_name": "Sarah E.",
"orcid": "0000-0001-8244-9300",
"clpid": "Reisman-S-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A nickel-catalyzed N\u2013N cross-coupling for the synthesis of hydrazides is reported. O-Benzoylated hydroxamates were efficiently coupled with a broad range of aryl and aliphatic amines via nickel catalysis to form hydrazides in an up to 81% yield. Experimental evidence implicates the intermediacy of electrophilic Ni-stabilized acyl nitrenoids and the formation of a Ni(I) catalyst via silane-mediated reduction. This report constitutes the first example of an intermolecular N\u2013N coupling compatible with secondary aliphatic amines.",
"doi": "10.1021/jacs.3c04834",
"pmcid": "PMC10360072",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-07-06",
"series_number": "28",
"volume": "145",
"issue": "28",
"pages": "15071-15077"
},
{
"id": "authors:gf3h3-cq877",
"collection": "authors",
"collection_id": "gf3h3-cq877",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230615-129167000.10",
"type": "article",
"title": "Tandem Dearomatization/Enantioselective Allylic Alkylation of Pyridines",
"author": [
{
"family_name": "Gre\u00dfies",
"given_name": "Steffen",
"clpid": "Gre\u00dfies-Steffen"
},
{
"family_name": "S\u00fc\u00dfe",
"given_name": "Lars",
"clpid": "S\u00fc\u00dfe-Lars"
},
{
"family_name": "Casselman",
"given_name": "Tyler",
"clpid": "Casselman-Tyler"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein, we report a multistep one-pot reaction of substituted pyridines leading to N-protected tetrahydropyridines with outstanding enantioselectivity (up to 97% ee). An iridium(I)-catalyzed dearomative 1,2-hydrosilylation of pyridines enables the use of N-silyl enamines as a new type of nucleophile in a subsequent palladium-catalyzed asymmetric allylic alkylation. This telescoped process overcomes the intrinsic nucleophilic selectivity of pyridines to synthesize enantioenriched, C-3-substituted tetrahydropyridine products that have been otherwise challenging to access.",
"doi": "10.1021/jacs.3c02470",
"pmcid": "PMC10251512",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-06-07",
"series_number": "22",
"volume": "145",
"issue": "22",
"pages": "11907-11913"
},
{
"id": "authors:eg3wd-7mj61",
"collection": "authors",
"collection_id": "eg3wd-7mj61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230607-310749000.5",
"type": "article",
"title": "Divergent Catalysis: Catalytic Asymmetric [4+2] Cycloaddition of Palladium Enolates",
"author": [
{
"family_name": "Flesch",
"given_name": "Kaylin N.",
"orcid": "0000-0002-8582-2614",
"clpid": "Flesch-Kaylin-N"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Chen",
"given_name": "Peng-Jui",
"orcid": "0000-0002-3594-0081",
"clpid": "Chen-Peng-Jui"
},
{
"family_name": "Strong",
"given_name": "Christian Santiago",
"clpid": "Strong-Christian-Santiago"
},
{
"family_name": "Sardini",
"given_name": "Stephen R.",
"orcid": "0000-0003-3643-4655",
"clpid": "Sardini-Stephen-R"
},
{
"family_name": "Du",
"given_name": "Yun E.",
"clpid": "Du-Yun-Emily"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An asymmetric decarboxylative [4+2] cycloaddition from a catalytically generated chiral Pd enolate was developed, forging four contiguous stereocenters in a single transformation. This was achieved through a strategy termed divergent catalysis, wherein departure from a known catalytic cycle enables novel reactivity of a targeted intermediate prior to re-entry into the original cycle. Mechanistic studies including quantum mechanics calculations, Eyring analysis, and KIE studies offer insight into the reaction mechanism.",
"doi": "10.1021/jacs.3c02104",
"pmcid": "PMC10388310",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-05-24",
"series_number": "20",
"volume": "145",
"issue": "20",
"pages": "11301-11310"
},
{
"id": "authors:hcyq2-y7d79",
"collection": "authors",
"collection_id": "hcyq2-y7d79",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230630-537205000.3",
"type": "article",
"title": "Total synthesis of (\u2212)-scabrolide A and (\u2212)-yonarolide",
"author": [
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-Steven-A"
},
{
"family_name": "Reimann",
"given_name": "Christopher E.",
"orcid": "0000-0003-3274-7590",
"clpid": "Reimann-Christopher-E"
},
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The complete account of the total syntheses of scabrolide A and yonarolide is disclosed. This article describes an initial approach involving a bio-inspired macrocyclization/transannular Diels\u2013Alder cascade, which ultimately failed due to undesired reactivity during macrocycle construction. Next, the evolution of a second and third strategy, which both involve an initial intramolecular Diels\u2013Alder reaction followed by a late-stage closure of the seven-membered ring of scabrolide A are detailed. The third strategy was first validated on a simplified system, but problems were encountered during a key [2 + 2] photocycloaddition on the fully elaborated system. An olefin protection strategy was employed to circumvent this problem, ultimately leading to the completion of the first total synthesis of scabrolide A and the closely related natural product yonarolide.",
"doi": "10.1039/d3sc00651d",
"pmcid": "PMC10173254",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2023-05-14",
"series_number": "18",
"volume": "14",
"issue": "18",
"pages": "4745-4758"
},
{
"id": "authors:qd3z8-a5d39",
"collection": "authors",
"collection_id": "qd3z8-a5d39",
"cite_using_url": "https://authors.library.caltech.edu/records/qd3z8-a5d39",
"type": "article",
"title": "Accretion product formation in the self-reaction of ethene-derived hydroxy peroxy radicals",
"author": [
{
"family_name": "Murphy",
"given_name": "Sara E.",
"orcid": "0000-0002-8226-9446",
"clpid": "Murphy-Sara-E"
},
{
"family_name": "Crounse",
"given_name": "John D.",
"orcid": "0000-0001-5443-729X",
"clpid": "Crounse-John-D"
},
{
"family_name": "M\u00f8ller",
"given_name": "Kristian H.",
"orcid": "0000-0001-8070-8516",
"clpid": "M\u00f8ller-Kristian-H"
},
{
"family_name": "Rezgui",
"given_name": "Samir P.",
"clpid": "Rezgui-Samir-P"
},
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Park",
"given_name": "James",
"clpid": "Park-James"
},
{
"family_name": "Kjaergaard",
"given_name": "Henrik G.",
"orcid": "0000-0002-7275-8297",
"clpid": "Kjaergaard-Henrik-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Wennberg",
"given_name": "Paul O.",
"orcid": "0000-0002-6126-3854",
"clpid": "Wennberg-P-O"
}
],
"abstract": "In this study we revisit one of the simplest RO\u2082\u2022 + RO\u2082\u2022 reactions: the self-reaction of the ethene-derived hydroxyperoxy radical formed via sequential addition of \u2022OH and O\u2082 to ethene. Previous studies of this reaction suggested that the branching to 'accretion products', compounds containing the carbon backbone of both reactants, was minimal. Here, CF\u2083O\u207b GC-CIMS is used to quantify the yields of ethylene glycol, glycolaldehyde, a hydroxy hydroperoxide produced from RO\u2082\u2022 + RO\u2082\u2022, and a C\u2084O\u2084H\u2081\u2080\naccretion product. These experiments were performed in an environmental chamber at 993 hPa and 294 K. We provide evidence that the accretion product is likely dihydroxy diethyl peroxide (HOC\u2082H\u2084OOC\u2082H\u2084OH=ROOR) and forms in the gas-phase with a branching fraction of 23 \u00b1 5%. We suggest a new channel in the RO\u2082\u2022 + RO\u2082\u2022 chemistry leading directly to the formation of HO\u2082 (together with glycolaldehyde and an alkoxy radical). Finally, by varying the ratio of the formation rate of RO\u2082 and HO\u2082 in our chamber, we constrain the ratio of the rate coefficient for the reaction of RO\u2082\u2022 + RO\u2082\u2022 to that of RO\u2082\u2022 + HO\u2082\u2022 and find that this ratio is 0.22 \u00b1 0.07, consistent with previous flash photolysis studies.",
"doi": "10.1039/d3ea00020f",
"issn": "2634-3606",
"publisher": "Royal Society of Chemistry",
"publication": "Environmental Science: Atmospheres",
"publication_date": "2023-05-01",
"series_number": "5",
"volume": "3",
"issue": "5",
"pages": "882-893"
},
{
"id": "authors:6prae-9qe77",
"collection": "authors",
"collection_id": "6prae-9qe77",
"cite_using_url": "https://authors.library.caltech.edu/records/6prae-9qe77",
"type": "article",
"title": "A Convergent Total Synthesis of (+)-Ineleganolide",
"author": [
{
"family_name": "Gross",
"given_name": "Benjamin M.",
"orcid": "0000-0002-9124-2317",
"clpid": "Gross-Benjamin-M"
},
{
"family_name": "Han",
"given_name": "Seo-Jung",
"orcid": "0000-0002-5812-3826",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report the total synthesis of the furanobutenolide-derived diterpenoid (+)-ineleganolide. The synthetic approach relies on a convergent strategy based on the coupling of two enantioenriched fragments, which are derived from (−)-linalool and (+)-norcarvone, respectively. A high-yielding, one-step Michael addition and aldol cascade furnishes a pentacyclic framework as a single diastereomer, thereby overcoming previous challenges in controlling stereochemistry. The endgame features an O2-facilitated C–H oxidation and a samarium diiodide-induced semipinacol rearrangement to furnish the highly rigid central seven-membered ring.
",
"doi": "10.1021/jacs.3c02142",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-04-12",
"series_number": "14",
"volume": "145",
"issue": "14",
"pages": "7763-7767"
},
{
"id": "authors:1nym7-p5r51",
"collection": "authors",
"collection_id": "1nym7-p5r51",
"cite_using_url": "https://authors.library.caltech.edu/records/1nym7-p5r51",
"type": "monograph",
"title": "A Convergent Total Synthesis of (+)-Ineleganolide",
"author": [
{
"family_name": "Gross",
"given_name": "Benjamin M.",
"orcid": "0000-0002-9124-2317",
"clpid": "Gross-Benjamin-M"
},
{
"family_name": "Han",
"given_name": "Seojung",
"clpid": "Han-Seojung"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report the total synthesis of the furanobutenolide-derived diterpenoid (+)-ineleganolide. The synthetic approach relies on a convergent strategy, based on the coupling of two enantioenriched fragments which are derived from (-)-linalool and (+)-norcarvone respectively. A high-yielding, one-step Michael addition and aldol cascade furnishes a pentacyclic framework as a single diastereomer, overcoming previous challenges in controlling stereochemistry. The endgame features an O\u2082 facilitated C-H oxidation and a samarium diiodide induced semi-pinacol rearrangement to furnish the highly rigid central seven membered ring.",
"doi": "10.1021/jacs.3c02142",
"pmcid": "PMC10544024",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-04-12",
"series_number": "14",
"volume": "145",
"issue": "14",
"pages": "7763-7767"
},
{
"id": "authors:2m2nm-3nt04",
"collection": "authors",
"collection_id": "2m2nm-3nt04",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230420-956212500.8",
"type": "article",
"title": "Total Synthesis of Strempeliopidine and Non-Natural Stereoisomers through a Convergent Petasis Borono-Mannich Reaction",
"author": [
{
"family_name": "Rand",
"given_name": "Alexander W.",
"orcid": "0000-0002-7099-5870",
"clpid": "Rand-Alexander-W"
},
{
"family_name": "Gonzalez",
"given_name": "Kevin J.",
"orcid": "0000-0002-4904-590X",
"clpid": "Gonzalez-Kevin-J"
},
{
"family_name": "Reimann",
"given_name": "Christopher E.",
"orcid": "0000-0003-3274-7590",
"clpid": "Reimann-Christopher-E"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Strempeliopidine is a member of the monoterpenoid bisindole alkaloid family, a class of natural products that have been shown to elicit an array of biological responses including modulating protein\u2013protein interactions in human cancer cells. Our synthesis of strempeliopidine leverages palladium-catalyzed decarboxylative asymmetric allylic alkylations to install the requisite all-carbon quaternary centers found in each of the two monomeric natural products, aspidospermidine and eburnamine. Initial studies employing Suzuki\u2013Miyaura cross-coupling followed by diastereoselective hydrogenation provided evidence for a structural reassignment of the natural product. Our final synthetic sequence employs a diastereoselective Petasis borono\u2013Mannich reaction to couple eburnamine to a trifluoroborate aspidospermidine derivative. These convergent approaches enabled the synthesis of eight diastereomers of this heterodimer and offer support for the reassignment of the absolute configuration of strempeliopidine.",
"doi": "10.1021/jacs.2c13146",
"pmcid": "PMC10281614",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2023-04-05",
"series_number": "13",
"volume": "145",
"issue": "13",
"pages": "7278-7287"
},
{
"id": "authors:cqrn7-qps14",
"collection": "authors",
"collection_id": "cqrn7-qps14",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230321-822411600.77",
"type": "article",
"title": "Development of a Non\u2010Directed Petasis\u2010Type Reaction by an Aromaticity\u2010Disrupting Strategy",
"author": [
{
"family_name": "Gonzalez",
"given_name": "Kevin J.",
"orcid": "0000-0002-4904-590X",
"clpid": "Gonzalez-Kevin-J"
},
{
"family_name": "Rand",
"given_name": "Alexander W.",
"orcid": "0000-0002-7099-5870",
"clpid": "Rand-Alexander-W"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The Petasis-type reaction, which couples an imine and boronic acid, is an important tool for C\u2212C bond formation in organic synthesis. However, the generality of this transformation has been limited by the requirement for a directing heteroatom to enable reactivity. Herein, we report the development of a non-directed Petasis-type reaction that allows for the coupling of trifluoroborate salts with \u03b1-hydroxyindoles. By disrupting aromaticity to generate a reactive iminium ion, in conjunction with using trifluoroborate nucleophiles, the method generates a new C\u2212C bond without the need for a directing group. This reaction is operationally simple, providing \u03b1-functionalized indoles in up to 99\u2009% yield using sp, sp\u00b2, and sp\u00b3-hybridized trifluoroborate nucleophiles. Finally, this reaction is applied as a novel bioconjugation strategy to link biologically active molecules and toward the convergent synthesis of non-natural heterodimeric bisindole alkaloid analogs.",
"pmcid": "PMC10033435",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2023-03-27",
"series_number": "14",
"volume": "62",
"issue": "14",
"pages": "e202218921"
},
{
"id": "authors:wd6hq-ncg82",
"collection": "authors",
"collection_id": "wd6hq-ncg82",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230203-890564800.1",
"type": "article",
"title": "What is a cross-coupling? An argument for a universal definition",
"author": [
{
"family_name": "Reimann",
"given_name": "Christopher E.",
"orcid": "0000-0003-3274-7590",
"clpid": "Reimann-Christopher-E"
},
{
"family_name": "Kim",
"given_name": "Kelly E.",
"orcid": "0000-0002-4132-2474",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Rand",
"given_name": "Alexander W.",
"orcid": "0000-0002-7099-5870",
"clpid": "Rand-Alexander-W"
},
{
"family_name": "Moghadam",
"given_name": "Farbod A.",
"clpid": "Moghadam-Farbod-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Despite amazing advances in cross-coupling technologies over the past several decades, there is not a consistent definition of what a cross-coupling reaction is. Often, definitions rely on comparison to \"traditional\" palladium-catalyzed cross-couplings pioneered in the 1970s by chemists such as Suzuki, Negishi, and Heck. While these reactions provide a basis for a cross-coupling definition, they do not define this type of transformation, originally described by Linstead almost 20 years prior. Rather than modify and compartmentalize modern transformations to categorize them into either a synthetic or mechanistic definition, we make an argument for broadening the cross-coupling definition to the union of two distinct molecular entities in a covalent-bond-forming process, to encourage discussion around exploring novel reactivity and disconnections. In addition to making a case for a universal cross-coupling definition, we cite specific examples of reactions that break the mold of prior cross-coupling definitions. We believe this perspective will stimulate dialog around what it means to be a cross-coupling and in turn inspire future developments within this field.",
"doi": "10.1016/j.tet.2022.133176",
"pmcid": "PMC9878734",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2023-01-09",
"volume": "130",
"pages": "133176"
},
{
"id": "authors:8fm38-crb41",
"collection": "authors",
"collection_id": "8fm38-crb41",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221128-494241100.52",
"type": "article",
"title": "Asymmetric Total Synthesis of Havellockate",
"author": [
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Chan",
"given_name": "Melinda",
"orcid": "0000-0002-2495-0110",
"clpid": "Chan-Melinda"
},
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-Steven-A"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first total synthesis of the furanobutenolide-derived cembranoid diterpenoid havellockate is disclosed. Our convergent strategy employs a Julia\u2013Kocienski olefination to join two enantioenriched fragments to produce a diene that is subsequently used in a propiolic acid esterification/Diels\u2013Alder cascade. This sequence generates the fused carbocyclic core of the natural product in short order. A challenging Zn-mediated Barbier allylation then forges the final C\u2013C bond and also establishes two vicinal stereogenic centers. Finally, a Cu-catalyzed aerobic oxidation facilitates the formation of the \u03b2-hydroxybutanolide to complete the total synthesis.",
"doi": "10.1021/jacs.2c09583",
"pmcid": "PMC9997676",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2022-11-09",
"series_number": "44",
"volume": "144",
"issue": "44",
"pages": "20232-20236"
},
{
"id": "authors:3e6x4-b3n94",
"collection": "authors",
"collection_id": "3e6x4-b3n94",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221216-550232000.1",
"type": "article",
"title": "Investigations of an Unexpected [2+2] Photocycloaddition in the Synthesis of (\u2212)-Scabrolide A from Quantum Mechanics Calculations",
"author": [
{
"family_name": "Zhang",
"given_name": "Tianyi",
"orcid": "0000-0001-8289-3102",
"clpid": "Zhang-Tianyi"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-Steven-A"
},
{
"family_name": "Reimann",
"given_name": "Christopher E.",
"orcid": "0000-0003-3274-7590",
"clpid": "Reimann-Christopher-E"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Goddard",
"given_name": "William A.",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "It is imperative to develop efficient CO\u2082 capture and activation technologies to combat the rising levels of deleterious greenhouse gases in the atmosphere. Using Quantum Mechanics methods (Density Functional Theory), we propose and evaluate several metal-free and metal-containing phosphines that provide strong CO\u2082 binding under ambient conditions. Depending on the electron donating capacity of the phosphine and the ability of the P-bound ligands to hydrogen bond to the CO\u2082, we find that the CO\u2082 binding can be as strong as \u221218.6 kcal/mol downhill, which should be quite adequate for ambient conditions. We explore some modifications of the phosphine to improve CO\u2082 binding, and we elucidate which chemical descriptors correlate directly with CO\u2082 binding energy. Specifically, we find that charge accumulation on the CO\u2082 unit of the CO\u2082-bound adduct has the greatest correlation with CO\u2082 binding affinity. Finally, we probe the mechanism for CO\u2082 reduction to CO and methanol in aqueous media.",
"doi": "10.1021/acs.joc.2c01693",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2022-11-04",
"series_number": "21",
"volume": "87",
"issue": "21",
"pages": "14115-14124"
},
{
"id": "authors:3dq8k-wms92",
"collection": "authors",
"collection_id": "3dq8k-wms92",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221114-800492800.1",
"type": "article",
"title": "Synthesis of enantioenriched 2,2-disubstituted pyrrolidines via sequential asymmetric allylic alkylation and ring contraction",
"author": [
{
"family_name": "Goldstein",
"given_name": "Elizabeth L.",
"orcid": "0000-0002-2208-6090",
"clpid": "Goldstein-Elizabeth-L"
},
{
"family_name": "Takada",
"given_name": "Hirokazu",
"orcid": "0000-0003-3452-6070",
"clpid": "Takada-Hirokazu"
},
{
"family_name": "Sumii",
"given_name": "Yuji",
"orcid": "0000-0003-3900-1089",
"clpid": "Sumii-Yuji"
},
{
"family_name": "Baba",
"given_name": "Katsuaki",
"clpid": "Baba-Katsuaki"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The synthesis of a variety of enantioenriched 2,2-disubstituted pyrrolidines is described. A stereogenic quaternary center is first formed utilizing an asymmetric allylic alkylation reaction of a benzyloxy imide, which can then be reduced to a chiral hydroxamic acid. This compound can then undergo a thermal \"Spino\" ring contraction to afford a carbamate protected 2,2-disubstituted pyrrolidine stereospecifically. These pyrrolidines can be further advanced to enantioenriched indolizidine compounds. This reaction sequence allows access to new molecules that could be useful in the development of pharmaceutical agents.",
"doi": "10.1016/j.tet.2022.132940",
"pmcid": "PMC10038171",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2022-09-24",
"volume": "123",
"pages": "Art. No. 132940"
},
{
"id": "authors:td2xs-6jr65",
"collection": "authors",
"collection_id": "td2xs-6jr65",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220606-735972000",
"type": "book_section",
"title": "Asymmetric allylic alkylation, allylation, and related reactions",
"book_title": "Catalytic Asymmetric Synthesis, Fourth Edition",
"author": [
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Du",
"given_name": "Yun E.",
"clpid": "Du-Yun-Emily"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"contributor": [
{
"family_name": "Akiyama",
"given_name": "Takahiko",
"clpid": "Akiyama-Takahiko"
},
{
"family_name": "Ojima",
"given_name": "Iwao",
"clpid": "Ojima-Iwao"
}
],
"abstract": "Transition-metal catalyzed asymmetric allylic substitution processes are powerful tactics for the enantioselective construction of a diverse scope of C-C bonds. This chapter highlights some of the most significant developments in the field of C-C bond forming asymmetric allylic substitutions from c. 2010\u20132020. This includes coverage of new developments in well-established Pd-catalysis, as well as the recent emergence of other metals such as Rh, Ir, and Cu. This entry endeavors to emphasize the increasing diversity and state-of-the-art in transition metal-catalyzed allylic substitutions rather than provide a comprehensive review.",
"doi": "10.1002/9781119736424.ch17",
"isbn": "9781119736424",
"publisher": "Wiley",
"place_of_publication": "New York, NY",
"publication_date": "2022-07-03",
"pages": "661-704"
},
{
"id": "authors:s9enx-7bp18",
"collection": "authors",
"collection_id": "s9enx-7bp18",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220520-649526000",
"type": "article",
"title": "Ir-Catalyzed Asymmetric Allylic Alkylation of Dialkyl Malonates Enabling the Construction of Enantioenriched All-Carbon Quaternary Centers",
"author": [
{
"family_name": "Moghadam",
"given_name": "Farbod A.",
"clpid": "Moghadam-Farbod-A"
},
{
"family_name": "Hicks",
"given_name": "Elliot F.",
"clpid": "Hicks-Elliot-F"
},
{
"family_name": "Sercel",
"given_name": "Zachary P.",
"clpid": "Sercel-Zachary-P"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective iridium-catalyzed allylic alkylation of malonates with trisubstituted allylic electrophiles to form all-carbon quaternary stereocenters is reported. This reaction proceeds at ambient temperature and enables the preparation of a wide range of enantioenriched products in up to 93% yield and 97% ee. The quaternary products can be readily converted to several valuable building blocks such as vicinal quaternary products and \u03b2-quaternary acids.",
"doi": "10.1021/jacs.2c02960",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2022-05-11",
"series_number": "18",
"volume": "144",
"issue": "18",
"pages": "7983-7987"
},
{
"id": "authors:wxsj5-p8f78",
"collection": "authors",
"collection_id": "wxsj5-p8f78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220302-956596361",
"type": "article",
"title": "Iridium-catalyzed asymmetric trans-selective hydrogenation of 1,3-disubstituted isoquinolines",
"author": [
{
"family_name": "Kim",
"given_name": "Alexia\u00a0N.",
"orcid": "0000-0002-4060-8892",
"clpid": "Kim-Alexia-N"
},
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development of the first asymmetric trans-selective hydrogenation of 1,3-disubstituted isoquinolines is reported. Utilizing [Ir(cod)Cl]\u2082 and a commercially available chiral Josiphos ligand, a variety of differentially substituted isoquinolines are hydrogenated to produce enantioenriched trans-tetrahydroisoquinolines in good yield with high levels of enantioselectivity. Directing group studies demonstrate that the hydroxymethyl functionality at the C1 position is critical for hydrogenation to favor the trans-diastereomer. Preliminary mechanistic studies reveal that non-coordinating chlorinated solvents and halide additives are crucial to enable trans-selectivity.",
"doi": "10.1039/d1sc06729j",
"pmcid": "PMC8926345",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2022-03-21",
"series_number": "11",
"volume": "13",
"issue": "11",
"pages": "3227-3232"
},
{
"id": "authors:hvjqy-p1005",
"collection": "authors",
"collection_id": "hvjqy-p1005",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220427-196780100",
"type": "monograph",
"title": "Part-per-trillion trace selective gas detection using frequency locked whispering gallery mode microtoroids",
"author": [
{
"family_name": "Li",
"given_name": "Cheng",
"clpid": "Li-Cheng"
},
{
"family_name": "Lohrey",
"given_name": "Trevor D.",
"orcid": "0000-0003-3568-7861",
"clpid": "Lohrey-Trevor-D"
},
{
"family_name": "Nguyen",
"given_name": "Phuong-Diem",
"clpid": "Nguyen-"
},
{
"family_name": "Min",
"given_name": "Zhouyang",
"clpid": "Min-Zhouyang"
},
{
"family_name": "Tang",
"given_name": "Yisha",
"clpid": "Tang-Yisha"
},
{
"family_name": "Ge",
"given_name": "Chang",
"clpid": "Ge-Chang"
},
{
"family_name": "Sercel",
"given_name": "Zachary P.",
"clpid": "Sercel-Zachary-P"
},
{
"family_name": "McLeod",
"given_name": "Euan",
"clpid": "McLeod-Euan"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Su",
"given_name": "Judith",
"orcid": "0000-0002-1005-1755",
"clpid": "Su-Judith"
}
],
"abstract": "Rapid detection of toxic and hazardous gases at trace concentrations plays a vital role in industrial, battlefield, and laboratory scenarios. Of interest are both sensitive as well as highly selective sensors. Whispering gallery mode (WGM) microresonator-based biochemical sensors are among the most sensitive sensors in existence due to their long photon confinement times. One main concern with these devices, however, is their selectivity towards specific classes of target analytes. Here, we employ frequency locked whispering gallery mode microtoroid optical resonators covalently modified with various polymer coatings to selectively detect the chemical warfare agent surrogate diisopropyl methylphosphonate (DIMP) as well as the toxic industrial chemicals formaldehyde and ammonia at parts-per-trillion concentrations. This is 1-2 orders of magnitude better than previously reported, depending on the target, except for pristine graphene and pristine carbon nanotube sensors, which demonstrate similar detection levels but in vacuum and without selectivity. Selective polymer coatings include polyethylene glycol (PEG) for DIMP sensing, accessed by the modification of commercially available materials, and 3-(triethoxysilyl)propyl-terminated polyvinyl acetate (PVAc) for ammonia sensing. Notably, we developed an efficient one-pot procedure to access 3-(triethoxysilyl)propyl-terminated PVAc that utilizes cobalt-mediated living radical polymerization and a nitroxyl polymer-terminating agent. Alkaline hydrolysis of PVAc coatings to form polyvinyl alcohol (PVA) coatings directly bound to the microtoroid proved to be reliable and reproducible, leading to WGM sensors capable of the rapid and selective detection of formaldehyde vapors. The selectivity of these three polymer coatings as sensing media was predicted, in part, based on their functional group content and known reactivity patterns with the target analytes. Furthermore, we demonstrate that microtoroids coated with a mixture of polymers can serve as an all-in-one sensor that can detect multiple agents. We anticipate that our results will facilitate rapid early detection of chemical agents, as well as their surrogates and precursors.",
"doi": "10.26434/chemrxiv-2022-606xv",
"publication_date": "2022-03-18"
},
{
"id": "authors:s07r2-zz403",
"collection": "authors",
"collection_id": "s07r2-zz403",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220322-742009000",
"type": "monograph",
"title": "Ir-Catalyzed Asymmetric Allylic Alkylation of Dialkyl Malo-nates Enabling the Construction of Enantioenriched All-Carbon Quaternary Centers",
"author": [
{
"family_name": "Moghadam",
"given_name": "Farbod A.",
"clpid": "Moghadam-Farbod-A"
},
{
"family_name": "Hicks",
"given_name": "Elliot F.",
"clpid": "Hicks-Elliot-F"
},
{
"family_name": "Sercel",
"given_name": "Zachary P.",
"clpid": "Sercel-Zachary-P"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective iridium-catalyzed allylic alkylation of malonates with trisubstituted allylic electrophiles to form all-carbon quaternary stereocenters is reported. This cross-coupling reaction features unprecedented reactivity at ambient temperature, particularly for challenging fully alkyl-substituted allylic electrophiles, and enables the preparation of a wide range of enantio-enriched products in up to 93% yield and 97% ee. The products of this transformation can be readily converted to a number of valuable building blocks including vicinal quaternary stereodiads and \u03b2-quaternary acids. This method was also used to prepare an enantioenriched intermediate facilitating the asymmetric formal synthesis of the sporochnol family of natural products.",
"doi": "10.26434/chemrxiv-2022-n4bsw",
"publication_date": "2022-03-18"
},
{
"id": "authors:00bft-cpd16",
"collection": "authors",
"collection_id": "00bft-cpd16",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220121-870770000",
"type": "article",
"title": "Isotope effects at the origin of life: Fingerprints of the Strecker synthesis",
"author": [
{
"family_name": "Chimiak",
"given_name": "L.",
"orcid": "0000-0002-5047-5421",
"clpid": "Chimiak-Laura"
},
{
"family_name": "Eiler",
"given_name": "J.",
"orcid": "0000-0001-5768-7593",
"clpid": "Eiler-J-M"
},
{
"family_name": "Sessions",
"given_name": "A.",
"orcid": "0000-0001-6120-2763",
"clpid": "Sessions-A-L"
},
{
"family_name": "Blumenfeld",
"given_name": "C.",
"clpid": "Blumenfeld-Carl-M"
},
{
"family_name": "Klatte",
"given_name": "M.",
"clpid": "Klatte-Max"
},
{
"family_name": "Stoltz",
"given_name": "B. M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Strecker synthesis creates \u03b1-amino acids from prebiotically plausible substrates (cyanide, ammonia, and aldehydes) and is widely hypothesized to be a key mechanism in the chemistry that led to life on Earth and on other planets. To better constrain the synthetic environments and precursors of abiotic \u03b1-amino acids, and to determine unique signatures of abiogenic amino acids, we measured the molecular-averaged and site-specific carbon and nitrogen isotope effects for the Strecker synthesis of alanine. The reaction steps of the Strecker synthesis can be divided into two groups: an initial series of reversible amination and nitrile-addition reactions ('equilibration') and a second series of irreversible hydrolysis reactions ('hydrolysis'). The equilibration of cyanide, acetaldehyde, and ammonia with the intermediate, \u03b1-aminopropionitrile (\u03b1-APN), has a measured 55.1\u2030 equilibrium nitrogen isotope effect between the \u00b9\u2075N-rich amine nitrogen in \u03b1-aminopropionitrile and the \u00b9\u2075N-poor ammonia and a 20.0\u2030 equilibrium carbon isotope effect between the \u00b9\u00b3C-poor C-2 site in \u03b1-aminopropionitrile and the \u00b9\u00b3C-rich carbonyl carbon in acetaldehyde. The first irreversible hydrolysis step is inferred to have an up to 10\u2030 normal carbon fractionation (i.e., faster for \u00b9\u00b2C, slower for \u00b9\u00b3C) for the whole molecule, but it also has one or more side reactions that deplete the reactive \u03b1-APN reservoir by up to 15\u2030. The second hydrolysis step has a 15.4\u2030 normal kinetic isotope effect on the amide (C-1) site of alaninamide, which becomes the carboxyl site of alanine. Other \u03b1-amino acids will likely experience similar nitrogen isotope fractionations between ammonia and their amine sites, and similar carbon isotope fractionations between the carbonyl carbon in reactant aldehydes or ketones and the intermediate \u03b1-aminonitrile, and between cyanide and the carboxyl site. Therefore, these isotope effects allow us to predict the carbon and nitrogen isotopic contents and intramolecular structures of \u03b1-amino acids formed by Strecker synthesis based on their substrates' isotopic compositions, or to infer the isotopic compositions of substrates from which amino acids formed, for example in the case of the amino-acid-rich carbonaceous chondrites. The site-specific C and N isotopic compositions of amino acids formed by Strecker chemistry contrast with those typical of terrestrial biosynthetic amino acids, so these data also provide a means of discriminating between biogenic and abiogenic \u03b1-amino acids.",
"doi": "10.1016/j.gca.2022.01.015",
"issn": "0016-7037",
"publisher": "Elsevier",
"publication": "Geochimica et Cosmochimica Acta",
"publication_date": "2022-03-15",
"volume": "321",
"pages": "78-98"
},
{
"id": "authors:2b84f-9tc42",
"collection": "authors",
"collection_id": "2b84f-9tc42",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220112-698034937",
"type": "article",
"title": "Some unusual transformations of a highly reactive \u03b1-bromocaranone",
"author": [
{
"family_name": "Samkian",
"given_name": "Adrian E.",
"orcid": "0000-0002-0068-3572",
"clpid": "Samkian-Adrian-E"
},
{
"family_name": "Sercel",
"given_name": "Zachary P.",
"clpid": "Sercel-Zachary-P"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The facile synthesis of a highly reactive \u03b1-bromocaranone from (+)-carene is reported. This intermediate was found to generate diverse chiral building blocks through radical or carbocation mediated cyclopropyl fragmentation reactions in moderate to excellent yields. Furthermore, the formation of an unexpected carvone derivative prompted several control studies that provided mechanistic insight into an unusual transformation. This study not only demonstrates the synthesis of a variety of chiral building blocks but provides insight into the reactivity of keto-halo-cyclopropanes in general.",
"doi": "10.1016/j.tetlet.2021.153496",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2022-01-19",
"volume": "89",
"pages": "Art. No. 153496"
},
{
"id": "authors:cssf9-can74",
"collection": "authors",
"collection_id": "cssf9-can74",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211012-211826965",
"type": "article",
"title": "Late-Stage Diversification: A Motivating Force in Organic Synthesis",
"author": [
{
"family_name": "Kim",
"given_name": "Kelly E.",
"orcid": "0000-0002-4132-2474",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Kim",
"given_name": "Alexia N.",
"orcid": "0000-0002-4060-8892",
"clpid": "Kim-Alexia-N"
},
{
"family_name": "McCormick",
"given_name": "Carter J.",
"clpid": "McCormick-Carter-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Interest in therapeutic discovery typically drives the preparation of natural product analogs, but these undertakings contribute significant advances for synthetic chemistry as well. The need for a highly efficient and scalable synthetic route to a complex molecular scaffold for diversification frequently inspires new methodological development or unique application of existing methods on structurally intricate systems. Additionally, synthetic planning with an aim toward late-stage diversification can provide access to otherwise unavailable compounds or facilitate preparation of complex molecules with diverse patterns of substitution around a shared carbon framework. For these reasons among others, programs dedicated to the diversification of natural product frameworks and other complex molecular scaffolds have been increasing in popularity, a trend likely to continue given their fruitfulness and breadth of impact. In this Perspective, we discuss our experience using late-stage diversification as a guiding principle for the synthesis of natural product analogs and reflect on the impact such efforts have on the future of complex molecule synthesis.",
"doi": "10.1021/jacs.1c08920",
"pmcid": "PMC9285880",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2021-10-20",
"series_number": "41",
"volume": "143",
"issue": "41",
"pages": "16890-16901"
},
{
"id": "authors:h85xr-eb257",
"collection": "authors",
"collection_id": "h85xr-eb257",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210821-142512577",
"type": "article",
"title": "Identifying the Imperative Role of Metal\u2013Olefin Interactions in Catalytic C\u2013O Reductive Elimination from Nickel(II)",
"author": [
{
"family_name": "Lohrey",
"given_name": "Trevor D.",
"orcid": "0000-0003-3568-7861",
"clpid": "Lohrey-Trevor-D"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We present a series of experimental and computational mechanistic investigations of an unusually facile example of Ni-catalyzed C\u2013O bond formation. Our method, originally reported in 2016, involves the formation of cyclic enol ethers from vinyl iodides bearing pendant alcohol groups. Our findings suggest that the observed reactivity arises from the coordination of the olefin in the vinyl iodide starting material and the enol ether product with Ni(0) intermediates. Density functional theory calculations reveal a plausible catalytic mechanism involving a Ni(II)/Ni(0) redox cycle featuring two-electron C\u2013I oxidative addition and C\u2013O reductive elimination steps. The direct formation of a \u03b72-enol ether Ni(0) complex from a key Ni(II) alkoxide intermediate dramatically alters the free energy (\u0394G) for the vinyl C\u2013O reductive elimination step relative to other examples of C\u2013O reductive elimination at Ni(II). Furthermore, efficient \u03c3-\u03c0 mixing in the course of vinyl C\u2013O reductive elimination leads to lower computed kinetic barriers (\u0394G\u2021) relative to those of aryl C\u2013O reductive elimination. The conclusions drawn from these computational models are supported by synthetic organometallic experiments, whereby a vinyl\u2013Ni(II) iodide intermediate was isolated, characterized, and proved to yield enol ether, following exposure to triethylamine. We conducted further experiments and computations, which indicated that the two-electron oxidative addition of vinyl iodides by Ni(0) depends on the formation of an \u03b7\u00b2-vinyl iodide precomplex, based on the observation of one-electron activation of the same vinyl iodide in the presence of sterically encumbering ligands (e.g., tricyclohexylphosphine).",
"doi": "10.1021/acscatal.1c02790",
"pmcid": "PMC8849544",
"issn": "2155-5435",
"publisher": "American Chemical Society",
"publication": "ACS Catalysis",
"publication_date": "2021-08-20",
"series_number": "16",
"volume": "11",
"issue": "16",
"pages": "10208-10222"
},
{
"id": "authors:44cy2-qaf78",
"collection": "authors",
"collection_id": "44cy2-qaf78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210823-170520379",
"type": "article",
"title": "Synthesis of Enantioenriched gem-Disubstituted 4-Imidazolidinones by Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation",
"author": [
{
"family_name": "Sercel",
"given_name": "Zachary P.",
"clpid": "Sercel-Zachary-P"
},
{
"family_name": "Sun",
"given_name": "Alexander W.",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A variety of enantioenriched gem-disubstituted 4-imidazolidinones were prepared in up to >99% yield and 95% ee by the Pd-catalyzed decarboxylative asymmetric allylic alkylation of imidazolidinone-derived \u03b2-amidoesters. In the process of preparing these substrates, a rapid synthetic route to 4-imidazolidinone derivatives was developed, beginning from 2-thiohydantoin. The orthogonality of the benzoyl imide and tert-butyl carbamate groups used to protect these nitrogen-rich products was demonstrated, enabling potential applications in drug design.",
"doi": "10.1021/acs.orglett.1c02134",
"pmcid": "PMC8534816",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2021-08-20",
"series_number": "16",
"volume": "23",
"issue": "16",
"pages": "6348-6351"
},
{
"id": "authors:kt114-w7h80",
"collection": "authors",
"collection_id": "kt114-w7h80",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210527-093457752",
"type": "article",
"title": "The Enantioselective Synthesis of Eburnamonine, Eucophylline, and 16\u2032-epi-Leucophyllidine",
"author": [
{
"family_name": "Reimann",
"given_name": "Christopher E.",
"orcid": "0000-0003-3274-7590",
"clpid": "Reimann-Christopher-E"
},
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Hayashida",
"given_name": "Kohei",
"clpid": "Hayashida-Kohei"
},
{
"family_name": "Saito",
"given_name": "Daisuke",
"clpid": "Saito-Daisuke"
},
{
"family_name": "Korch",
"given_name": "Katerina M.",
"orcid": "0000-0002-1436-8792",
"clpid": "Korch-Katerina-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A synthetic approach to the heterodimeric bisindole alkaloid leucophyllidine is disclosed herein. An enantioenriched lactam building block, synthesized through palladium-catalyzed asymmetric allylic alkylation, served as the precursor to both hemispheres. The eburnamonine-derived fragment was synthesized through a Bischler\u2013Napieralski/hydrogenation approach, while the eucophylline-derived fragment was synthesized by Friedl\u00e4nder quinoline synthesis and two sequential C\u2212H functionalization steps. A convergent Stille coupling and phenol-directed hydrogenation united the two monomeric fragments to afford 16\u2032-epi-leucophyllidine in 21 steps from commercial material.",
"doi": "10.1002/anie.202106184",
"pmcid": "PMC8338904",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2021-08-09",
"series_number": "33",
"volume": "60",
"issue": "33",
"pages": "17957-17962"
},
{
"id": "authors:p6vet-s5c82",
"collection": "authors",
"collection_id": "p6vet-s5c82",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211214-174138725",
"type": "conference_item",
"title": "Reductive elimination from palladium(II) via a [\u03c02s + \u03c02s + \u03c32s + \u03c32s] pericyclic reaction",
"author": [
{
"family_name": "Cusumano",
"given_name": "Alexander",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Goddard",
"given_name": "William Andrew",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian Mark",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The fundamental step responsible for enantioinduction in the inner-sphere asym. Tsuji allylic alkylation is C-C bond formation through a unique seven-membered pericyclic transition state. We investigate how the electronic structure of the transition metal center enables the C-C bond forming process. Phase inversion introduced by d orbitals renders the Pd-catalyzed [\u03c02s + \u03c02s + \u03c32s + \u03c32s] reaction symmetry-allowed in the ground state - proceeding through a transition state with Craig-M\u00f6bius-like aromaticity. We connect these findings to ubiquitous bonding concepts, such as Frontier MO theory and valence bonding theory.",
"publisher": "Caltech Library",
"publication_date": "2021-08"
},
{
"id": "authors:87vq4-v8t39",
"collection": "authors",
"collection_id": "87vq4-v8t39",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210629-212235037",
"type": "article",
"title": "Synthetic strategy toward ineleganolide: A cautionary tale",
"author": [
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-Kendall-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We present a case study to demonstrate how complex molecule synthesis can benefit from quantum mechanics (QM) calculations. Theory is applied in two contexts: testing the chemical intuition used in retrosynthetic planning, along with expediting the resolution of unexpected challenges encountered during the course of the synthesis. From a computational lens, we examine retrospectively the strategies employed and the decisions made during our synthetic efforts toward the diterpenoid natural product ineleganolide. Seemingly logical and robust hypotheses are found to be ill-fated after theoretical investigation. Prior knowledge of these issues may have potentially saved valuable time and resources during our synthetic efforts. This cautionary tale suggests that synthetic campaigns can benefit from computational evaluation of synthetic plans.",
"doi": "10.1016/j.tet.2021.132289",
"pmcid": "PMC8294177",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2021-07-30",
"volume": "93",
"pages": "Art. No. 132289"
},
{
"id": "authors:wds3g-tkv10",
"collection": "authors",
"collection_id": "wds3g-tkv10",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210507-140316316",
"type": "article",
"title": "Discovery of novel modulators for the PPAR\u03b1 (peroxisome proliferator activated receptor \u03b1): Potential therapies for nonalcoholic fatty liver disease",
"author": [
{
"family_name": "Yu",
"given_name": "Donna D.",
"clpid": "Yu-Donna-D"
},
{
"family_name": "Van Citters",
"given_name": "Gregg",
"clpid": "Van-Citters-Gregg"
},
{
"family_name": "Li",
"given_name": "Hongzhi",
"clpid": "Li-Hongzhi"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Forman",
"given_name": "Barry M.",
"clpid": "Forman-Barry-M"
}
],
"abstract": "Nonalcoholic fatty liver disease (NAFLD) is a severe liver disease causing serious liver complications, including nonalcoholic steatohepatitis (NASH). Nuclear receptor PPAR\u03b1 (peroxisome proliferator-activated receptor \u03b1) has drawn special attention recently as a potential developmental drug target to treat type-2 diabetes and related diseases due to its unique functions in regulating lipid metabolism, promoting triglyceride oxidation, and suppressing hepatic inflammation, raising interest in PPAR\u03b1 agonists as potential therapies for NAFLD. However, how PPAR\u03b1 coordinates potential treatment of NAFLD and NASH between various metabolic pathways is still obscure. Here, we show that the DY series of novel selective PPAR\u03b1 modulators activate PPAR\u03b1 by up-regulating PPAR\u03b1 target genes directly involved in NAFLD and NASH. The design, synthesis, docking studies, and in vitro and in vivo evaluation of the novel DY series of PPAR\u03b1 agonists are described.",
"doi": "10.1016/j.bmc.2021.116193",
"issn": "0968-0896",
"publisher": "Elsevier",
"publication": "Bioorganic and Medicinal Chemistry",
"publication_date": "2021-07-01",
"volume": "41",
"pages": "Art. No. 116193"
},
{
"id": "authors:kds5b-3qy24",
"collection": "authors",
"collection_id": "kds5b-3qy24",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210416-080746750",
"type": "article",
"title": "A Synthetic Strategy toward Eight-Membered Cyclic Amines by Cycloetherification and Claisen Rearrangement",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Cavitt",
"given_name": "Marchello A.",
"clpid": "Cavitt-Marchello-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Eight-membered nitrogen-containing heterocycles were straightforwardly produced by a nickel-catalyzed cycloetherification and subsequent Claisen rearrangement of secondary and tertiary alcohols. In particular, a one-pot transformation was achieved with tertiary alcohols in moderate to good yields. This operationally simple reaction is tolerant of many functional groups and applicable to the synthesis of various medium-sized ring nitrogen-containing heterocycles.",
"doi": "10.1021/acs.orglett.1c00763",
"pmcid": "PMC8846577",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2021-05-07",
"series_number": "9",
"volume": "23",
"issue": "9",
"pages": "3300-3303"
},
{
"id": "authors:40q72-hqc08",
"collection": "authors",
"collection_id": "40q72-hqc08",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210212-132145336",
"type": "article",
"title": "Enantioselective Formation of Quaternary Centers by Allylic Alkylation with First-Row Transition-Metal Catalysts",
"author": [
{
"family_name": "S\u00fcsse",
"given_name": "Lars",
"clpid": "S\u00fcsse-Lars"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Asymmetric allylic alkylation mediated by transition metals provides an efficient strategy to form quaternary stereogenic centers. While this transformation is dominated by the use of second- and third-row transition metals (e.g., Pd, Rh, and Ir), recent developments have revealed the potential of first-row transition metals, which provide not only a less expensive and potentially equally efficient alternative but also new mechanistic possibilities. This review summarizes examples for the assembly of quaternary stereocenters using prochiral allylic substrates and hard, achiral nucleophiles in the presence of copper complexes and highlights the complementary approaches with soft, prochiral nucleophiles catalyzed by chiral cobalt and nickel complexes.",
"doi": "10.1021/acs.chemrev.0c01115",
"pmcid": "PMC8846597",
"issn": "0009-2665",
"publisher": "American Chemical Society",
"publication": "Chemical Reviews",
"publication_date": "2021-04-14",
"series_number": "7",
"volume": "121",
"issue": "7",
"pages": "4084-4099"
},
{
"id": "authors:5b58b-qz615",
"collection": "authors",
"collection_id": "5b58b-qz615",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210104-164231600",
"type": "article",
"title": "A covalent p97/VCP ATPase inhibitor can overcome resistance to CB-5083 and NMS-873 in colorectal cancer cells",
"author": [
{
"family_name": "Zhang",
"given_name": "Gang",
"clpid": "Zhang-Gang"
},
{
"family_name": "Li",
"given_name": "Shan",
"clpid": "Li-Shan"
},
{
"family_name": "Wang",
"given_name": "Feng",
"clpid": "Wang-Feng"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-7445-8311",
"clpid": "Jones-Amanda-C"
},
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-Alexander-F-G"
},
{
"family_name": "Lin",
"given_name": "Benjamin",
"orcid": "0000-0002-0580-6818",
"clpid": "Lin-Benjamin"
},
{
"family_name": "Virgil",
"given_name": "Scott",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Deshaies",
"given_name": "Raymond J.",
"orcid": "0000-0002-3671-9354",
"clpid": "Deshaies-R-J"
},
{
"family_name": "Chou",
"given_name": "Tsui-Fen",
"orcid": "0000-0003-2410-2186",
"clpid": "Chou-Tsui-Fen"
}
],
"abstract": "Small-molecule inhibitors of p97 are useful tools to study p97 function. Human p97 is an important AAA ATPase due to its diverse cellular functions and implication in mediating the turnover of proteins involved in tumorigenesis and virus infections. Multiple p97 inhibitors identified from previous high-throughput screening studies are thiol-reactive compounds targeting Cys522 in the D2 ATP-binding domain. Thus, these findings suggest a potential strategy to develop covalent p97 inhibitors. We first used purified p97 to assay several known covalent kinase inhibitors to determine if they can inhibit ATPase activity. We evaluated their selectivity using our dual reporter cells that can distinguish p97 dependent and independent degradation. We selected a \u03b2-nitrostyrene scaffold to further study the structure-activity relationship. In addition, we used p97 structures to design and synthesize analogues of pyrazolo[3,4-d]pyrimidine (PP). We incorporated electrophiles into a PP-like compound 17 (4-amino-1-tert-butyl-3-phenyl pyrazolo[3,4-d]pyrimidine) to generate eight compounds. A selective compound 18 (N-(1-(tert-butyl)-3-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)acrylamide, PPA) exhibited excellent selectivity in an in vitro ATPase activity assay: IC50 of 0.6 \u03bcM, 300 \u03bcM, and 100 \u03bcM for wild type p97, yeast Cdc48, and N-ethylmaleimide sensitive factor (NSF), respectively. To further examine the importance of Cys522 on the active site pocket during PPA inhibition, C522A and C522T mutants of p97 were purified and shown to increase IC50 values by 100-fold, whereas replacement of Thr532 of yeast Cdc48 with Cysteine decreased the IC50 by 10-fold. The molecular modeling suggested the hydrogen bonds and hydrophobic interactions in addition to the covalent bonding at Cys522 between WT-p97 and PPA. Furthermore, tandem mass spectrometry confirmed formation of a covalent bond between Cys522 and PPA. An anti-proliferation assay indicated that the proliferation of HCT116, HeLa, and RPMI8226 was inhibited by PPA with IC50 of 2.7 \u03bcM, 6.1 \u03bcM, and 3.4 \u03bcM, respectively. In addition, PPA is able to inhibit proliferation of two HCT116 cell lines that are resistant to CB-5083 and NMS-873, respectively. Proteomic analysis of PPA-treated HCT116 revealed Gene Ontology enrichment of known p97 functional pathways such as the protein ubiquitination and the ER to Golgi transport vesicle membrane. In conclusion, we have identified and characterized PPA as a selective covalent p97 inhibitor, which will allow future exploration to improve the potency of p97 inhibitors with different mechanisms of action.",
"doi": "10.1016/j.ejmech.2020.113148",
"pmcid": "PMC7954469",
"issn": "0223-5234",
"publisher": "Elsevier",
"publication": "European Journal of Medicinal Chemistry",
"publication_date": "2021-03-05",
"volume": "213",
"pages": "Art. No. 113148"
},
{
"id": "authors:23xky-zp684",
"collection": "authors",
"collection_id": "23xky-zp684",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220421-197072600",
"type": "book_section",
"title": "Part-per-trillion trace gas detection using frequency-locked whispering gallery mode microtoroids",
"book_title": "Integrated Optics: Devices, Materials, and Technologies XXV",
"author": [
{
"family_name": "Li",
"given_name": "Cheng",
"clpid": "Li-Cheng"
},
{
"family_name": "Lohrey",
"given_name": "Trevor",
"orcid": "0000-0003-3568-7861",
"clpid": "Lohrey-Trevor-D"
},
{
"family_name": "Nguyen",
"given_name": "Phuong-Diem",
"clpid": "Nguyen-Phuong-Diem"
},
{
"family_name": "Min",
"given_name": "Zhouyang",
"clpid": "Min-Zhouyang"
},
{
"family_name": "Stoltz",
"given_name": "Brian",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Su",
"given_name": "Judith",
"clpid": "Su-Judith"
}
],
"contributor": [
{
"family_name": "Garc\u00eda-Blanco",
"given_name": "Sonia M.",
"clpid": "Garc\u00eda-Blanco-Sonia-M"
},
{
"family_name": "Cheben",
"given_name": "Pavel",
"clpid": "Cheben-Pavel"
}
],
"abstract": "We use a system known as FLOWER (frequency locked optical whispering evanescent resonator) to rapidly detect trace amounts of the chemical warfare agent surrogates DIMP and DMMP. We use sorbent polymer layers covalently bound to the surface of the microtoroid cavity to selectively adsorb target gases. As the target gas diffuses into the polymer layer, a measurable change in the resonance frequency of the toroid occurs. We demonstrate 80 ppt (part per trillion) sensing of DIMP; two orders of magnitude better than what can be achieved using mass spectroscopy.",
"doi": "10.1117/12.2578032",
"isbn": "9781510642133",
"publisher": "Society of Photo-Optical Instrumentation Engineers",
"place_of_publication": "Bellingham, WA",
"publication_date": "2021-03-05",
"pages": "Art. No. 116890B"
},
{
"id": "authors:wym7y-ftm15",
"collection": "authors",
"collection_id": "wym7y-ftm15",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-857271000.57",
"type": "article",
"title": "Discussion Addendum for: Preparation of (S)-tert-ButylPyOx and Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids",
"author": [
{
"family_name": "Sardini",
"given_name": "Stephen R.",
"orcid": "0000-0003-3643-4655",
"clpid": "Sardini-Stephen-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "[no abstract]",
"doi": "10.15227/orgsyn.098.0117",
"pmcid": "PMC9558615",
"issn": "2333-3553",
"publisher": "Organic Syntheses, Inc.",
"publication": "Organic Syntheses",
"publication_date": "2021",
"volume": "98",
"pages": "117-130"
},
{
"id": "authors:yg5v4-nam80",
"collection": "authors",
"collection_id": "yg5v4-nam80",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201104-135041447",
"type": "article",
"title": "Global Diastereoconvergence in the Ireland\u2013Claisen Rearrangement of Isomeric Enolates: Synthesis of Tetrasubstituted \u03b1-Amino Acids",
"author": [
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Du",
"given_name": "Yun E.",
"clpid": "Du-Yun-Emily"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-Kendall-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A dual experimental/theoretical investigation of the Ireland\u2013Claisen rearrangement of tetrasubstituted \u03b1-phthalimido ester enolates to afford \u03b1-tetrasubstituted, \u03b2-trisubstituted \u03b1-amino acids (generally >20:1 dr) is described. For trans allylic olefins, the Z- and E-enol ethers proceed through chair and boat transition states, respectively. For cis allylic olefins, the trend is reversed. As a result, the diastereochemical outcome of the reaction is preserved regardless of the geometry of the enolate or the accompanying allylic olefin. We term this unique convergence of all possible olefin isomers global diastereoconvergence. This reaction manifold circumvents limitations in present-day technologies for the stereoselective enolization of \u03b1,\u03b1-disubstituted allyl esters. Density functional theory paired with state-of-the-art local coupled-cluster theory (DLPNO-CCSD(T)) was employed for the accurate determination of quantum mechanical energies.",
"doi": "10.1021/jacs.0c11480",
"pmcid": "PMC8552564",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2020-12-30",
"series_number": "52",
"volume": "142",
"issue": "52",
"pages": "21938-21947"
},
{
"id": "authors:qfs02-rr325",
"collection": "authors",
"collection_id": "qfs02-rr325",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191105-093732898",
"type": "article",
"title": "Synthesis of non-natural cyanthiwigin\u2013gagunin hybrids through late-stage diversification of the cyanthiwigin natural product core",
"author": [
{
"family_name": "Kim",
"given_name": "Kelly E.",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Sakazaki",
"given_name": "Yuka",
"clpid": "Sakazaki-Yuka"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Derivitization of natural product scaffolds produces diversely functionalized molecules for biological study and offers insight into the reactivities of complex molecular architectures. In the present study, the tricyclic framework of the cyanthiwigin natural product family was employed as a platform for late-stage diversification. The design and synthesis of several non-natural \"hybrid\" molecules resembling both the cyanthiwigin and gagunin natural products was accomplished, and the results of these investigations are described herein.",
"doi": "10.1016/j.tet.2019.130755",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2020-12-18",
"series_number": "51",
"volume": "76",
"issue": "51",
"pages": "Art. No. 130755"
},
{
"id": "authors:y0eta-rc666",
"collection": "authors",
"collection_id": "y0eta-rc666",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201112-103611899",
"type": "article",
"title": "Recent Advances in Homogeneous Catalysts for the Asymmetric Hydrogenation of Heteroarenes",
"author": [
{
"family_name": "Kim",
"given_name": "Alexia N.",
"orcid": "0000-0002-4060-8892",
"clpid": "Kim-Alexia-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The asymmetric hydrogenation of heteroarenes has recently emerged as an effective strategy for the direct access to enantioenriched, saturated heterocycles. Although several homogeneous catalyst systems have been extensively developed for the hydrogenation of heteroarenes with high levels of chemo- and stereoselectivity, the development of mild conditions that allow for efficient and stereoselective hydrogenation of a broad range of substrates remains a challenge. This Perspective highlights recent advances in homogeneous catalysis of heteroarene hydrogenation as inspiration for the further development of asymmetric hydrogenation catalysts, and addresses underdeveloped areas and limitations of the current technology.",
"doi": "10.1021/acscatal.0c03958",
"pmcid": "PMC8460131",
"issn": "2155-5435",
"publisher": "American Chemical Society",
"publication": "ACS Catalysis",
"publication_date": "2020-12-04",
"series_number": "23",
"volume": "10",
"issue": "23",
"pages": "13834-13851"
},
{
"id": "authors:5q252-gyj56",
"collection": "authors",
"collection_id": "5q252-gyj56",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201028-103039420",
"type": "article",
"title": "Transition Metal Catalyzed [\u03c02s + \u03c02s + \u03c32s + \u03c32s] Pericyclic Reaction: Woodward\u2013Hoffmann Rules, Aromaticity, and Electron Flow",
"author": [
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We have shown that the fundamental step responsible for enantioinduction in the inner-sphere asymmetric Tsuji allylic alkylation is C\u2013C bond formation through a seven-membered pericyclic transition state. We employ an extensive series of quantum mechanics (QM) calculations to delineate how the electronic structure of the Pd-catalyzed C\u2013C bond forming process controls the reaction. Phase inversion introduced by d orbitals renders the Pd-catalyzed [\u03c02s + \u03c02s + \u03c32s + \u03c32s] reaction symmetry-allowed in the ground state, proceeding through a transition state with Craig\u2013M\u00f6bius-like \u03c3-aromaticity. Lastly, we connect QM to fundamental valence bonding concepts by deriving an ab initio \"arrow-pushing\" mechanism that describes the flow of electron density through the reaction.",
"doi": "10.1021/jacs.0c09575",
"pmcid": "PMC8549492",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2020-11-11",
"series_number": "45",
"volume": "142",
"issue": "45",
"pages": "19033-19039"
},
{
"id": "authors:826va-sm395",
"collection": "authors",
"collection_id": "826va-sm395",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200925-104734427",
"type": "article",
"title": "Enantioselective synthesis of highly oxygenated acyclic quaternary center-containing building blocks via palladium-catalyzed decarboxylative allylic alkylation of cyclic siloxyketones",
"author": [
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Iwayama",
"given_name": "Toshihiko",
"clpid": "Iwayama-Toshihiko"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development of a palladium-catalyzed enantioselective decarboxylative allylic alkylation of cyclic siloxyketones to produce enantioenriched silicon-tethered heterocycles is reported. The reaction proceeds smoothly to provide products bearing a quaternary stereocenter in excellent yields (up to 91% yield) with high levels of enantioselectivity (up to 94% ee). We further utilized the unique reactivity of the siloxy functionality to access chiral, highly oxygenated acyclic quaternary building blocks. In addition, we subsequently demonstrated the utility of these compounds through the synthesis of a lactone bearing vicinal quaternary-trisubstituted stereocenters.",
"doi": "10.1039/d0sc04383d",
"pmcid": "PMC8162308",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2020-10-28",
"series_number": "40",
"volume": "11",
"issue": "40",
"pages": "11068-11071"
},
{
"id": "authors:efyea-8nv30",
"collection": "authors",
"collection_id": "efyea-8nv30",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200304-153439734",
"type": "article",
"title": "Enantioselective Total Synthesis of (\u2013)-Myrifabral A and B",
"author": [
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Chen",
"given_name": "Anthony Y.",
"orcid": "0000-0002-9578-4893",
"clpid": "Chen-Anthony-Y"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic enantioselective approach to the Myrioneuron alkaloids (\u2212)-myrifabral A and (\u2212)-myrifabral B is described. The synthesis was enabled by a palladium-catalyzed enantioselective allylic alkylation, that generates the C(10) all-carbon quaternary center. A key N-acyl iminium ion cyclization forged the cyclohexane fused tricyclic core, while vinyl boronate cross metathesis and oxidation afforded the lactol ring of (\u2212)-myrifabral A. Adaptation of previously reported conditions allowed for the conversion of (\u2212)-myrifabral A to (\u2212)-myrifabral B.",
"doi": "10.1039/d0sc01141j",
"pmcid": "PMC8162428",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2020-10-21",
"series_number": "39",
"volume": "11",
"issue": "39",
"pages": "10802-10806"
},
{
"id": "authors:9wb0x-mgr33",
"collection": "authors",
"collection_id": "9wb0x-mgr33",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200819-162804852",
"type": "article",
"title": "Synthesis of Carboxylic Acid and Dimer Ester Surrogates to Constrain the Abundance and Distribution of Molecular Products in \u03b1-Pinene and \u03b2-Pinene Secondary Organic Aerosol",
"author": [
{
"family_name": "Kenseth",
"given_name": "Christopher M.",
"orcid": "0000-0003-3188-2336",
"clpid": "Kenseth-Christopher-M"
},
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Huang",
"given_name": "Yuanlong",
"orcid": "0000-0002-6726-8904",
"clpid": "Huang-Yuanlong"
},
{
"family_name": "Dalleska",
"given_name": "Nathan F.",
"orcid": "0000-0002-2059-1587",
"clpid": "Dalleska-Nathan-F"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Seinfeld",
"given_name": "John H.",
"orcid": "0000-0003-1344-4068",
"clpid": "Seinfeld-J-H"
}
],
"abstract": "Liquid chromatography/negative electrospray ionization mass spectrometry [LC/(\u2212)ESI-MS] is routinely employed to characterize the identity and abundance of molecular products in secondary organic aerosol (SOA) derived from monoterpene oxidation. Due to a lack of authentic standards, however, commercial terpenoic acids (e.g., cis-pinonic acid) are typically used as surrogates to quantify both monomeric and dimeric SOA constituents. Here, we synthesize a series of enantiopure, pinene-derived carboxylic acid and dimer ester homologues. We find that the (\u2212)ESI efficiencies of the dimer esters are 19\u201336 times higher than that of cis-pinonic acid, demonstrating that the mass contribution of dimers to monoterpene SOA has been significantly overestimated in past studies. Using the measured (\u2212)ESI efficiencies of the carboxylic acids and dimer esters as more representative surrogates, we determine that molecular products measureable by LC/(\u2212)ESI-MS account for only 21.8 \u00b1 2.6% and 18.9 \u00b1 3.2% of the mass of SOA formed from ozonolysis of \u03b1-pinene and \u03b2-pinene, respectively. The 28\u201336 identified monomers (C\u2087\u208b\u2081\u2080H\u2081\u2080\u208b\u2081\u2088O\u2083\u208b\u2086) constitute 15.6\u201320.5% of total SOA mass, whereas only 1.3\u20133.3% of the SOA mass is attributable to the 46\u201362 identified dimers (C\u2081\u2085\u208b\u2081\u2089H\u2082\u2084\u208b\u2083\u2082O\u2084\u208b\u2081\u2081). The distribution of identified \u03b1-pinene and \u03b2-pinene SOA molecular products is examined as a function of carbon number (n_C), average carbon oxidation state (OS_C), and volatility (C*). The observed order-of-magnitude difference in (\u2212)ESI efficiency between monomers and dimers is expected to be broadly applicable to other biogenic and anthropogenic SOA systems analyzed via (\u2212) or (+) LC/ESI-MS under various LC conditions, and demonstrates that the use of unrepresentative surrogates can lead to substantial systematic errors in quantitative LC/ESI-MS analyses of SOA.",
"doi": "10.1021/acs.est.0c01566",
"issn": "0013-936X",
"publisher": "American Chemical Society",
"publication": "Environmental Science and Technology",
"publication_date": "2020-10-20",
"series_number": "20",
"volume": "54",
"issue": "20",
"pages": "12829-12839"
},
{
"id": "authors:nt108-xxh46",
"collection": "authors",
"collection_id": "nt108-xxh46",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200911-133138265",
"type": "article",
"title": "Efficient Synthesis of Geminal-Dialkyl Dienes for Olefin Metathesis Polymerization",
"author": [
{
"family_name": "Wolf",
"given_name": "William J.",
"orcid": "0000-0001-6755-8920",
"clpid": "Wolf-William-J"
},
{
"family_name": "Li",
"given_name": "Jiaming",
"orcid": "0000-0001-6646-5693",
"clpid": "Li-Jiaming"
},
{
"family_name": "Jones",
"given_name": "Simon C.",
"orcid": "0000-0002-1952-3720",
"clpid": "Jones-Simon-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "A robust synthesis of gem-dialkyl acyclic diene monomers has been developed. This route is scalable, flexible, and biorenewable, allowing for the production of a wide range of diene monomers of different lengths and different gem-dialkyl substitutions starting from unsaturated esters derived from seed oils. The metathesis polymerization of these monomers and the hydrogenation of the resulting polyolefins lead to telechelic gem-dialkyl polyethylenes, which can be used as elastomers in the synthesis of polyurethanes and other block polymers.",
"doi": "10.1021/acs.macromol.0c01606",
"pmcid": "PMC8297823",
"issn": "0024-9297",
"publisher": "American Chemical Society",
"publication": "Macromolecules",
"publication_date": "2020-09-22",
"series_number": "18",
"volume": "53",
"issue": "18",
"pages": "7803-7809"
},
{
"id": "authors:tnr12-zn027",
"collection": "authors",
"collection_id": "tnr12-zn027",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200710-102850852",
"type": "article",
"title": "Reaction Mechanism, Origins of Enantioselectivity, and Reactivity Trends in Asymmetric Allylic Alkylation: A Comprehensive Quantum Mechanics Investigation of a C(sp\u00b3)\u2013C(sp\u00b3) Cross-Coupling",
"author": [
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
}
],
"abstract": "We utilize quantum mechanics to evaluate a variety of plausible mechanistic pathways for the entirety of the catalytic cycle for asymmetric decarboxylative allylic alkylation of allyl \u03b2-ketoesters. We present a mechanistic picture that unites all current experimental observations, including enantioinduction, reaction rate, catalyst resting state, enolate crossover experiments, water tolerance, and the effects of solvation on inner- and outer-sphere mechanisms. Experiments designed to evaluate the fidelity and predictive power of the computational models reveal the methods employed herein to be highly effective in elucidating the reactivity of the catalytic system. On the basis of these findings, we highlight a computational framework from which chemically accurate results are obtained and address the current limitations of the decarboxylative asymmetric allylic alkylation reaction.",
"doi": "10.1021/jacs.0c06243",
"pmcid": "PMC7802888",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2020-08-12",
"series_number": "32",
"volume": "142",
"issue": "32",
"pages": "13917-13933"
},
{
"id": "authors:8680x-shp96",
"collection": "authors",
"collection_id": "8680x-shp96",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201221-084129753",
"type": "conference_item",
"title": "Synthesis of carboxylic acid and dimer ester surrogates to constrain the abundance and distribution of\n molecular products in \u03b1-pinene and \u03b2-pinene secondary organic aerosol",
"author": [
{
"family_name": "Kenseth",
"given_name": "Christopher M.",
"orcid": "0000-0003-3188-2336",
"clpid": "Kenseth-Christopher-M"
},
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Huang",
"given_name": "Yuanlong",
"orcid": "0000-0002-6726-8904",
"clpid": "Huang-Yuanlong"
},
{
"family_name": "Dalleska",
"given_name": "Nathan F.",
"orcid": "0000-0002-2059-1587",
"clpid": "Dalleska-Nathan-F"
},
{
"family_name": "Stoltz",
"given_name": "Brian Mark",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Seinfeld",
"given_name": "John H.",
"orcid": "0000-0003-1344-4068",
"clpid": "Seinfeld-J-H"
}
],
"abstract": "Liq. chromatog./neg. electrospray ionization mass spectrometry [LC/(-)ESI-MS] is routinely employed to characterize the\nidentity and abundance of mol. products in secondary org. aerosol (SOA) derived from monoterpene oxidn. Due to a\nlack of authentic stds., however, com. terpenoic acids (e.g., cis-pinonic acid) are typically used as surrogates to\nquantify both monomeric and dimeric SOA constituents. Here, we synthesize a series of enantiopure, pinene-derived\ncarboxylic acid and dimer ester homologues. We find that the (-)ESI efficiencies of the dimer esters are 19 to 36 times\nhigher than that of cis-pinonic acid, demonstrating that the mass contribution of dimers to monoterpene SOA has\nbeen significantly overestimated in past studies. Using the measured (-)ESI efficiencies of the carboxylic acids and\ndimer esters as more representative surrogates, we det. that mol. products measureable by LC/(-)ESI-MS account for\nonly 21.8 \u00b1 2.6% and 18.9 \u00b1 3.2% of the mass of SOA formed from ozonolysis of \u03b1-pinene and \u03b2-pinene, resp. The 28-\n36 identified monomers (C\u2087\u208b\u2081\u2080H\u2081\u2080\u208b\u2081\u2088O\u2083\u208b\u2086) constitute 15.6-20.5% of total SOA mass, whereas only 1.3-3.3% of the SOA\nmass is attributable to the 46-62 identified dimers (C\u2081\u2085\u208b\u2081\u2089H\u2082\u2084\u208b\u2083\u2082O\u2084\u208b\u2081\u2081). The distribution of identified \u03b1-pinene and \u03b2-pinene SOA mol. products is examd. as a function of carbon no. (n_C), av. carbon oxidn. state (OS_C), and volatility\n(C*). The obsd. order of magnitude difference in (-)ESI efficiency between monomers and dimers is expected to be\nbroadly applicable to other biogenic and anthropogenic SOA systems analyzed via (-) or (+) LC/ESI-MS, and\ndemonstrates that the use of unrepresentative surrogates can lead to substantial systematic errors in quant. LC/ESI-MS\nanalyses of SOA.",
"publisher": "Caltech Library",
"publication_date": "2020-08"
},
{
"id": "authors:4yef4-hy289",
"collection": "authors",
"collection_id": "4yef4-hy289",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200702-103837298",
"type": "article",
"title": "Catalytic enantioselective synthesis of carbocyclic and heterocyclic spiranes via a decarboxylative aldol cyclization",
"author": [
{
"family_name": "Inanaga",
"given_name": "Kazato",
"clpid": "Inanaga-Kazato"
},
{
"family_name": "Wollenburg",
"given_name": "Marco",
"clpid": "Wollenburg-Marco"
},
{
"family_name": "Bachman",
"given_name": "Shoshana",
"clpid": "Bachman-Shoshana"
},
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The synthesis of a variety of enantioenriched 1,3-diketospiranes from the corresponding racemic allyl \u03b2-ketoesters via an interrupted asymmetric allylic alkylation is disclosed. Substrates possessing pendant aldehydes undergo decarboxylative enolate formation in the presence of a chiral Pd catalyst and subsequently participate in an enantio- and diastereoselective, intramolecular aldol reaction to furnish spirocyclic \u03b2-hydroxy ketones which may be oxidized to the corresponding enantioenriched diketospiranes. Additionally, this chemistry has been extended to \u03b1-allylcarboxy lactam substrates leading to a formal synthesis of the natural product (\u2212)-isonitramine.",
"doi": "10.1039/d0sc02366c",
"pmcid": "PMC7574022",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2020-07-28",
"series_number": "28",
"volume": "11",
"issue": "28",
"pages": "7390-7395"
},
{
"id": "authors:j5pvr-n2z71",
"collection": "authors",
"collection_id": "j5pvr-n2z71",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200622-104137176",
"type": "article",
"title": "Probing Trends in Enantioinduction via Substrate Design: Palladium-Catalyzed Decarboxylative Allylic Alkylation of \u03b1-Enaminones",
"author": [
{
"family_name": "Duquette",
"given_name": "Douglas C.",
"clpid": "Duquette-Douglas-C"
},
{
"family_name": "Cusumano",
"given_name": "Alexander Q.",
"orcid": "0000-0002-2914-2008",
"clpid": "Cusumano-Alexander-Q"
},
{
"family_name": "Lefoulon",
"given_name": "Louise",
"clpid": "Lefoulon-Louise"
},
{
"family_name": "Moore",
"given_name": "Jared T.",
"clpid": "Moore-Jared-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein, we report the palladium-catalyzed decarboxylative asymmetric allylic alkylation of \u03b1-enaminones. In addition to serving as valuable synthetic building blocks, we exploit the \u03b1-enaminone scaffold and its derivatives as probes to highlight structural and electronic factors that govern enantioselectivity in this asymmetric alkylation reaction. Utilizing the (S)-t-BuPHOX ligand in a variety of nonpolar solvents, the alkylated products are obtained in up to 99% yield and 99% enantiomeric excess.",
"doi": "10.1021/acs.orglett.0c01441",
"pmcid": "PMC7608880",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2020-07-02",
"series_number": "13",
"volume": "22",
"issue": "13",
"pages": "4966-4969"
},
{
"id": "authors:myw3a-6q597",
"collection": "authors",
"collection_id": "myw3a-6q597",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200519-093555551",
"type": "article",
"title": "Palladium-Catalyzed Enantioselective Decarboxylative Allylic Alkylation of Acyclic \u03b1-N-Pyrrolyl/Indolyl Ketones",
"author": [
{
"family_name": "Lavernhe",
"given_name": "R\u00e9mi",
"clpid": "Lavernhe-R\u00e9mi"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The synthesis of fully substituted \u03b1-N-pyrrolyl and indolyl ketones via enantioselective palladium-catalyzed allylic alkylation is described. The acyclic ketones are alkylated in high yields with high enantioselectivities through the use of an electron-deficient phosphinooxazoline ligand, furnishing a highly congested and synthetically challenging stereocenter. The obtained alkylation products contain multiple reactive sites poised for additional functionalizations and diversification.",
"doi": "10.1021/acs.orglett.0c01303",
"pmcid": "PMC7608871",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2020-06-05",
"series_number": "11",
"volume": "22",
"issue": "11",
"pages": "4272-4275"
},
{
"id": "authors:xyagr-e1g39",
"collection": "authors",
"collection_id": "xyagr-e1g39",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200420-124420412",
"type": "article",
"title": "Catalytic enantioselective synthesis of tetrasubstituted chromanones via palladium-catalyzed asymmetric conjugate arylation using chiral pyridine-dihydroisoquinoline ligands",
"author": [
{
"family_name": "Baek",
"given_name": "Doohyun",
"orcid": "0000-0003-4059-2832",
"clpid": "Baek-Doohyun"
},
{
"family_name": "Ryu",
"given_name": "Huijeong",
"orcid": "0000-0002-9877-1852",
"clpid": "Ryu-Huijeong"
},
{
"family_name": "Ryu",
"given_name": "Ji Yeon",
"clpid": "Ryu-Ji-Yeon"
},
{
"family_name": "Lee",
"given_name": "Junseong",
"orcid": "0000-0002-5004-7865",
"clpid": "Lee-Junseong"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Hong",
"given_name": "Sukwon",
"orcid": "0000-0002-2078-9630",
"clpid": "Hong-Sukwon"
}
],
"abstract": "Highly enantioselective conjugate addition reactions of arylboronic acids to 2-substituted chromones catalyzed by palladium complexes with new chiral Pyridine-Dihydroisoquinoline (PyDHIQ) ligands have been developed. These reactions provide highly enantioselective access to chromanones containing tetrasubstituted stereocenters. Various arylboronic acids and 2-substituted chromones can be used in the catalytic reaction to afford the chiral tetrasubstituted chromanones in good yields and excellent enantioselectivities (25 examples, up to 98% yields, up to 99% ee).",
"doi": "10.1039/d0sc00412j",
"pmcid": "PMC7574023",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2020-05-14",
"series_number": "18",
"volume": "11",
"issue": "18",
"pages": "4602-4607"
},
{
"id": "authors:ckfhq-aqp13",
"collection": "authors",
"collection_id": "ckfhq-aqp13",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200304-101308383",
"type": "article",
"title": "The Total Synthesis of (\u2013)-Scabrolide A",
"author": [
{
"family_name": "Hafeman",
"given_name": "Nicholas J.",
"orcid": "0000-0001-7525-7597",
"clpid": "Hafeman-Nicholas-J"
},
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-Steven-A"
},
{
"family_name": "Reimann",
"given_name": "Christopher E.",
"clpid": "Reimann-Christopher-E"
},
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first total synthesis of the norcembranoid diterpenoid scabrolide A is disclosed. The route begins with the synthesis of two chiral pool-derived fragments, which undergo a convergent coupling to expediently introduce all 19 carbon atoms of the natural product. An intramolecular Diels\u2013Alder reaction and an enone\u2013olefin cycloaddition/fragmentation sequence are then employed to construct the fused [5\u20136\u20137] linear carbocyclic core of the molecule and complete the total synthesis.",
"doi": "10.1021/jacs.0c02513",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2020-05-13",
"series_number": "19",
"volume": "142",
"issue": "19",
"pages": "8585-8590"
},
{
"id": "authors:9hx8h-77473",
"collection": "authors",
"collection_id": "9hx8h-77473",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200211-083029861",
"type": "article",
"title": "Iridium-Catalyzed Enantioselective and Diastereoselective Hydrogenation of 1,3-Disubstituted Isoquinolines",
"author": [
{
"family_name": "Kim",
"given_name": "Alexia N.",
"orcid": "0000-0002-4060-8892",
"clpid": "Kim-Alexia-N"
},
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Welin",
"given_name": "Eric R.",
"orcid": "0000-0002-1760-4121",
"clpid": "Welin-Eric-R"
},
{
"family_name": "Daiger",
"given_name": "Martin T.",
"clpid": "Daiger-Martin-T"
},
{
"family_name": "Gr\u00fcnanger",
"given_name": "Christian U.",
"clpid": "Gr\u00fcnanger-Christian-U"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development of a general method utilizing a hydroxymethyl directing group for asymmetric hydrogenation of 1,3-disubstituted isoquinolines to provide chiral 1,2,3,4-tetrahydroisoquinolines is reported. The reaction, which utilizes [Ir(cod)Cl]\u2082 and a commercially available chiral xyliphos ligand, proceeds in good yield with high levels of enantioselectivity and diastereoselectivity (up to 95% ee and >20:1 dr) on a range of differentially substituted isoquinolines. Directing-group studies demonstrate that the hydroxymethyl functional group at the C1 position is more efficient at enabling hydrogenation in comparison to other substituents, although high levels of enantioselectivity were conserved across a variety of polar and nonpolar functional groups. By utilization of the generated chiral \u03b2-amino alcohol as a functional handle, the synthetic utility is further highlighted via the synthesis of 1,2-fused oxazolidine, oxazolidinone, and morpholinone tetrahydroisoquinolines in one step. Additionally, a non-natural analogue of the tetrahydroprotoberberine alkaloids was successfully synthesized.",
"doi": "10.1021/acscatal.0c00211",
"pmcid": "PMC8152574",
"issn": "2155-5435",
"publisher": "American Chemical Society",
"publication": "ACS Catalysis",
"publication_date": "2020-03-06",
"series_number": "5",
"volume": "10",
"issue": "5",
"pages": "3241-3248"
},
{
"id": "authors:tm16c-9gz24",
"collection": "authors",
"collection_id": "tm16c-9gz24",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191120-075819004",
"type": "article",
"title": "Copper-Catalyzed Enantioselective Allylic Alkylation with a \u03b3-Butyrolactone-Derived Silyl Ketene Acetal",
"author": [
{
"family_name": "Jette",
"given_name": "Carina I.",
"orcid": "0000-0002-8476-6032",
"clpid": "Jette-Carina-I"
},
{
"family_name": "Tong",
"given_name": "Z. Jaron",
"orcid": "0000-0001-9329-8034",
"clpid": "Tong-Zhengjia-Jaron"
},
{
"family_name": "Hadt",
"given_name": "Ryan G.",
"orcid": "0000-0001-6026-1358",
"clpid": "Hadt-R-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein, we report a Cu\u2010catalyzed enantioselective allylic alkylation using a \u03b3\u2010butyrolactone\u2010derived silyl ketene acetal. Critical to the development of this work was the identification of a novel mono\u2010picolinamide ligand with the appropriate steric and electronic properties to afford the desired products in high yield (up to 96\u2009%) and high ee (up to 95\u2009%). Aryl, aliphatic, and unsubstituted allylic chlorides bearing a broad range of functionality are well\u2010tolerated. Spectroscopic studies reveal that a Cu^I species is likely the active catalyst, and DFT calculations suggest ligand sterics play an important role in determining Cu coordination and thus catalyst geometry.",
"doi": "10.1002/anie.201912618",
"pmcid": "PMC7051182",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2020-01-27",
"series_number": "5",
"volume": "59",
"issue": "5",
"pages": "2033-2038"
},
{
"id": "authors:9xd2q-kfr38",
"collection": "authors",
"collection_id": "9xd2q-kfr38",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191106-101057290",
"type": "article",
"title": "Palladium-Catalyzed Enantioselective Decarboxylative Allylic Alkylation of Protected Benzoin-Derived Enol Carbonates",
"author": [
{
"family_name": "Lavernhe",
"given_name": "R\u00e9mi",
"clpid": "Lavernhe-R\u00e9mi"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The enantioselective palladium-catalyzed decarboxylative allylic alkylation of fully substituted \u03b1-hydroxy acyclic enol carbonates providing tetrasubstituted benzoin derivatives is reported. Investigation into the transformation revealed that preparation of the starting material as a single enolate isomer is crucial for optimal\nenantioselectivity. The obtained alkylation products\ncontain multiple reactive sites that can be utilized toward\nthe synthesis of stereochemically rich derivatives.",
"doi": "10.1002/adsc.201901281",
"pmcid": "PMC7942817",
"issn": "1615-4150",
"publisher": "Wiley",
"publication": "Advanced Synthesis and Catalysis",
"publication_date": "2020-01-23",
"series_number": "2",
"volume": "362",
"issue": "2",
"pages": "344-347"
},
{
"id": "authors:92xq5-cwc21",
"collection": "authors",
"collection_id": "92xq5-cwc21",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191112-095230680",
"type": "article",
"title": "Enantioselective Alkynylation of Trifluoromethyl Ketones Catalyzed by Cation-Binding Salen Nickel Complexes",
"author": [
{
"family_name": "Park",
"given_name": "Dongseong",
"clpid": "Park-Dongseong"
},
{
"family_name": "Jette",
"given_name": "Carina I.",
"orcid": "0000-0002-8476-6032",
"clpid": "Jette-C-I"
},
{
"family_name": "Kim",
"given_name": "Jiyun",
"clpid": "Kim-Jiyun"
},
{
"family_name": "Jung",
"given_name": "Woo-ok",
"clpid": "Jung-Woo-ok"
},
{
"family_name": "Lee",
"given_name": "Yongmin",
"clpid": "Lee-Yongmin"
},
{
"family_name": "Park",
"given_name": "Jongwoo",
"clpid": "Park-Jongwoo"
},
{
"family_name": "Kang",
"given_name": "Seungyoon",
"clpid": "Kang-Seungyoon"
},
{
"family_name": "Han",
"given_name": "Min Su",
"clpid": "Han-Min-Su"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Hong",
"given_name": "Sukwon",
"clpid": "Hong-Sukwon"
}
],
"abstract": "Cation\u2010binding salen nickel catalysts were developed for the enantioselective alkynylation of trifluoromethyl ketones in high yield (up to 99\u2009%) and high enantioselectivity (up to 97\u2009% ee). The reaction proceeds with substoichiometric quantities of base (10\u201320 mol\u2009% KOt\u2010Bu) and open to air. In the case of trifluoromethyl vinyl ketones, excellent chemo\u2010selectivity was observed, generating 1,2\u2010addition products exclusively over 1,4\u2010addition products. UV\u2010vis analysis revealed the pendant oligo\u2010ether group of the catalyst strongly binds to the potassium cation (K\u207a) with 1:1 binding stoichiometry (K_a=6.6\u00d710\u2075\u2009M\u207b\u00b9).",
"doi": "10.1002/anie.201913057",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2020-01-07",
"series_number": "2",
"volume": "59",
"issue": "2",
"pages": "775-779"
},
{
"id": "authors:ff5xg-dmm50",
"collection": "authors",
"collection_id": "ff5xg-dmm50",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191209-080257479",
"type": "article",
"title": "Enantioselective Synthesis of 15-Deoxy-\u0394\u00b9\u00b2,\u00b9\u2074-Prostaglandin J\u2082",
"author": [
{
"family_name": "Li",
"given_name": "Jiaming",
"orcid": "0000-0001-6646-5693",
"clpid": "Li-Jiaming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "An enantioselective synthesis of 15-deoxy-\u0394\u00b9\u00b2,\u00b9\u2074-prostaglandin J\u2082 is reported. The synthesis begins with the preparation of enantiopure 3-oxodicyclopentadiene by a lipase-mediated kinetic resolution. A three-component coupling followed by a retro-Diels\u2013Alder reaction provides the C8 stereochemistry of the prostaglandin skeleton with high enantioselectivity. Stereoretentive olefin metathesis followed by a Pinnick oxidation affords 15-deoxy-\u0394\u00b9\u00b2,\u00b9\u2074-prostaglandin J\u2082 in high enantiopurity.",
"doi": "10.1021/acs.orglett.9b04198",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2019-12-20",
"series_number": "24",
"volume": "21",
"issue": "24",
"pages": "10139-10142"
},
{
"id": "authors:gqj6s-fda65",
"collection": "authors",
"collection_id": "gqj6s-fda65",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191008-075046379",
"type": "article",
"title": "Enantioselective construction of the tricyclic core of curcusones A\u2013D via a cross-electrophile coupling approach",
"author": [
{
"family_name": "Wright",
"given_name": "Austin C.",
"clpid": "Wright-Austin-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein we report our recent progress toward the enantioselective total synthesis of the diterpenoid natural products curcusones A\u2013D by means of complementary Stetter annulation or ring-closing metathesis (RCM) disconnections. Using the latter approach, we have achieved the concise construction of the 5\u20137\u20136 carbocyclic core embedded in each member of the curcusone family. Essential to this route is the use of a cross-electrophile coupling strategy, which has not previously been harnessed in the context of natural product synthesis.",
"doi": "10.1039/c9sc04127c",
"pmcid": "PMC6988747",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2019-12-07",
"series_number": "45",
"volume": "10",
"issue": "45",
"pages": "10562-10565"
},
{
"id": "authors:6f1qc-caj70",
"collection": "authors",
"collection_id": "6f1qc-caj70",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191125-151328722",
"type": "article",
"title": "Progress toward the Enantioselective Synthesis of Curcusones A\u2013D via a Divinylcyclopropane Rearrangement Strategy",
"author": [
{
"family_name": "Wright",
"given_name": "Austin C.",
"clpid": "Wright-A-C"
},
{
"family_name": "Lee",
"given_name": "Chung Whan",
"clpid": "Lee-Chung-Whan"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report our iterative efforts toward the divergent total syntheses of curcusones A\u2013D via Suzuki coupling, intramolecular cyclopropanation, and a key divinylcyclopropane rearrangement. Progress of our synthesis was repeatedly challenged by the highly substrate-dependent cyclopropanation step, which we could ultimately overcome by judicious choice of substituents on the six-membered ring fragment.",
"doi": "10.1021/acs.orglett.9b03829",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2019-12-06",
"series_number": "23",
"volume": "21",
"issue": "23",
"pages": "9658-9662"
},
{
"id": "authors:f719n-ved68",
"collection": "authors",
"collection_id": "f719n-ved68",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191030-100426727",
"type": "article",
"title": "Stereospecific Overman Rearrangement of Substituted Cyclic Vinyl Bromides: Access to Fully Substituted \u03b1-Amino Ketones",
"author": [
{
"family_name": "Velasco-Rubio",
"given_name": "\u00c1lvaro",
"orcid": "0000-0003-1477-4747",
"clpid": "Velasco-Rubio-\u00c1"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-E-J"
},
{
"family_name": "Yoritate",
"given_name": "Makoto",
"clpid": "Yoritate-Makoto"
},
{
"family_name": "Wright",
"given_name": "Austin C.",
"clpid": "Wright-A-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A versatile thermal Overman rearrangement of enantioenriched, cyclic allylic alcohols providing tertiary allylic amines has been developed. The vinyl bromide used to control enantioselectivity in a preceding CBS reduction is utilized as a synthetic handle for the preparation of tertiary \u03b1-amino ketones and related derivatives in an asymmetric fashion.",
"doi": "10.1021/acs.orglett.9b03347",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2019-11-15",
"series_number": "22",
"volume": "21",
"issue": "22",
"pages": "8962-8965"
},
{
"id": "authors:tvmtm-s7w29",
"collection": "authors",
"collection_id": "tvmtm-s7w29",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191031-141639871",
"type": "article",
"title": "Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of 1,4-Diazepan-5-ones",
"author": [
{
"family_name": "Sercel",
"given_name": "Zachary P.",
"clpid": "Sercel-Zachary-P"
},
{
"family_name": "Sun",
"given_name": "Alexander W.",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report the palladium-catalyzed asymmetric allylic alkylation of 1,4-diazepan-5-ones. This reaction proceeds smoothly to give gem-disubstituted diazepanone heterocycles bearing various functional groups in up to >99% yield and up to 95% ee. An electron-rich p-anisoyl lactam protecting group and the use of a nonpolar solvent proved crucial to obtaining high enantioselectivity in most cases. Additionally, we demonstrate the use of our methodology in the synthesis of a gem-disubstituted analogue of the FDA-approved anti-insomnia drug suvorexant.",
"doi": "10.1021/acs.orglett.9b03530",
"pmcid": "PMC8579948",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2019-11-15",
"series_number": "22",
"volume": "21",
"issue": "22",
"pages": "9158-9161"
},
{
"id": "authors:nx1nn-k5s93",
"collection": "authors",
"collection_id": "nx1nn-k5s93",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191111-083817296",
"type": "book_section",
"title": "Transition\u2010Metal\u2010Free Catalytic C\u2500H Bond Silylation",
"book_title": "Organosilicon Chemistry: Novel Approaches and Reactions",
"author": [
{
"family_name": "Schuman",
"given_name": "David P.",
"clpid": "Schuman-David-P"
},
{
"family_name": "Liu",
"given_name": "Wen\u2010Bo",
"clpid": "Liu-Wen\u2010Bo"
},
{
"family_name": "Nesnas",
"given_name": "Nasri",
"orcid": "0000-0003-3511-940X",
"clpid": "Nesnas-Nasri"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"contributor": [
{
"family_name": "Hiyama",
"given_name": "Tamejiro",
"clpid": "Hiyama-Tamejiro"
},
{
"family_name": "Oestreich",
"given_name": "Martin",
"clpid": "Oestreich-Martin"
}
],
"abstract": "Herein, we provide a detailed look at the state of transition\u2010metal\u2010free catalytic C\u2013H silylation with select examples to highlight specific advances during the field's recent development. The reactions are categorized by type of catalyst (i.e. Lewis acid, Br\u00f8nsted acid, Br\u00f8nsted base, and radical initiation catalysts). For each catalyst system presented, an overview of the substrate scope, mechanism (if known), and significant limitations is discussed.",
"doi": "10.1002/9783527814787.ch7",
"isbn": "9783527344536",
"publisher": "Wiley",
"publication_date": "2019-11-08",
"pages": "213-240"
},
{
"id": "authors:5279n-st450",
"collection": "authors",
"collection_id": "5279n-st450",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190624-132958661",
"type": "article",
"title": "Modularity: Adding New Dimensions to Total Synthesis",
"author": [
{
"family_name": "Sun",
"given_name": "Alexander W.",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Lackner",
"given_name": "Sebastian",
"clpid": "Lackner-S"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "As the field of synthetic chemistry seeks to tackle new frontiers, total synthesis is primed to address significant medical challenges such as the rise of antibiotic resistance and cancer. One emerging frontier focuses on increasingly concerted efforts to utilize modular total synthesis as a strategy to generate analogs of natural product targets for biological studies, with the ultimate goal of new therapeutic development. This new frontier is enabled by a confluence of human ingenuity in synthetic design, newly developed reactions that facilitate advances in total synthesis strategies, and emerging technologies. In this review, we highlight the evolving trend of modular total synthesis, including new reactions and automated technologies. This trend should lead to an increasingly important source of new medicines to improve human health.",
"doi": "10.1016/j.trechm.2019.05.008",
"issn": "2589-5974",
"publisher": "Elsevier",
"publication": "Trends in Chemistry",
"publication_date": "2019-10",
"series_number": "7",
"volume": "1",
"issue": "7",
"pages": "630-643"
},
{
"id": "authors:8qe50-h9q18",
"collection": "authors",
"collection_id": "8qe50-h9q18",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190906-134149357",
"type": "article",
"title": "Characterization of Reactive Organometallic Species via MicroED",
"author": [
{
"family_name": "Jones",
"given_name": "Christopher G.",
"clpid": "Jones-Christopher-G"
},
{
"family_name": "Asay",
"given_name": "Matthew",
"clpid": "Assay-Matthew"
},
{
"family_name": "Kim",
"given_name": "Lee Joon",
"clpid": "Kim-Lee-Joon"
},
{
"family_name": "Kleinsasser",
"given_name": "Jack F.",
"clpid": "Kleinsasser-Jack-F"
},
{
"family_name": "Saha",
"given_name": "Ambarneil",
"clpid": "Saha-Ambarneil"
},
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Berkley",
"given_name": "Kevin R.",
"clpid": "Berkley-Kevin-R"
},
{
"family_name": "Cascio",
"given_name": "Duilio",
"clpid": "Cascio-Duilio"
},
{
"family_name": "Malyutin",
"given_name": "Andrey G.",
"orcid": "0000-0003-1716-5437",
"clpid": "Malyutin-Andrey-G"
},
{
"family_name": "Conley",
"given_name": "Matthew P.",
"clpid": "Conley-Matthew-P"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Lavallo",
"given_name": "Vincent",
"orcid": "0000-0001-8945-3038",
"clpid": "Lavallo-Vincent"
},
{
"family_name": "Rodriguez",
"given_name": "Jose A.",
"clpid": "Rodriguez-Jose-A"
},
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
}
],
"abstract": "Here we apply microcrystal electron diffraction (MicroED) to the structural determination of transition-metal complexes. We find that the simultaneous use of 300 keV electrons, very low electron doses, and an ultrasensitive camera allows for the collection of data without cryogenic cooling of the stage. This technique reveals the first crystal structures of the classic zirconocene hydride, colloquially known as \"Schwartz's reagent\", a novel Pd(II) complex not amenable to solution-state NMR or X-ray crystallography, and five other paramagnetic and diamagnetic transition-metal complexes.",
"doi": "10.1021/acscentsci.9b00403",
"pmcid": "PMC6764211",
"issn": "2374-7943",
"publisher": "American Chemical Society",
"publication": "ACS Central Science",
"publication_date": "2019-09-25",
"series_number": "9",
"volume": "5",
"issue": "9",
"pages": "1507-1513"
},
{
"id": "authors:nr6h4-01981",
"collection": "authors",
"collection_id": "nr6h4-01981",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190718-083115245",
"type": "article",
"title": "Incorporation of a chiral gem-disubstituted nitrogen heterocycle yields an oxazolidinone antibiotic with reduced mitochondrial toxicity",
"author": [
{
"family_name": "Sun",
"given_name": "Alexander W.",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Bulterys",
"given_name": "Philip L.",
"clpid": "Bulterys-Philip-L"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Jorth",
"given_name": "Peter A.",
"orcid": "0000-0002-0981-740X",
"clpid": "Jorth-Peter-A"
},
{
"family_name": "O'Boyle",
"given_name": "Brendan M.",
"clpid": "O'Boyle-Brendan-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Miller",
"given_name": "Jeff F.",
"clpid": "Miller-Jeff-F"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "gem-Disubstituted N-heterocycles are rarely found in drugs, despite their potential to improve the drug-like properties of small molecule pharmaceuticals. Linezolid, a morpholine heterocycle-containing oxazolidinone antibiotic, exhibits significant side effects associated with human mitochondrial protein synthesis inhibition. We synthesized a gem-disubstituted linezolid analogue that when compared to linezolid, maintains comparable (albeit slightly diminished) activity against bacteria, comparable in vitro physicochemical properties, and a decrease in undesired mitochondrial protein synthesis (MPS) inhibition. This research contributes to the structure-activity-relationship data surrounding oxazolidinone MPS inhibition, and may inspire investigations into the utility of gem-disubstituted N-heterocycles in medicinal chemistry.",
"doi": "10.1016/j.bmcl.2019.07.024",
"pmcid": "PMC6711789",
"issn": "0960-894X",
"publisher": "Elsevier",
"publication": "Bioorganic and Medicinal Chemistry Letters",
"publication_date": "2019-09-15",
"series_number": "18",
"volume": "29",
"issue": "18",
"pages": "2686-2689"
},
{
"id": "authors:11ead-hnm76",
"collection": "authors",
"collection_id": "11ead-hnm76",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190812-105551569",
"type": "article",
"title": "A Small-scale Procedure for Acid-catalyzed Ketal Formation",
"author": [
{
"family_name": "Wright",
"given_name": "Austin C.",
"clpid": "Wright-A-C"
},
{
"family_name": "Du",
"given_name": "Yun Emily",
"clpid": "Du-Yun-Emily"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A modified procedure for dehydrative ketal protections is disclosed, which serves as an alternative to the classic Dean\u2013Stark protocol. Studies show that this new procedure can outperform the Dean\u2013Stark apparatus on small scales and thus serves as a complementary approach to effect dehydrative ketalizations. A detailed procedure for this apparatus is presented.",
"doi": "10.1021/acs.joc.9b01541",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2019-09-06",
"series_number": "17",
"volume": "84",
"issue": "17",
"pages": "11258-11260"
},
{
"id": "authors:edtzz-qhn71",
"collection": "authors",
"collection_id": "edtzz-qhn71",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190603-092206331",
"type": "article",
"title": "Palladium-catalyzed \u03b1,\u03b2-dehydrogenation of acyclic ester equivalents promoted by a novel electron deficient phosphinooxazoline ligand",
"author": [
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Wu",
"given_name": "Brenda",
"clpid": "Wu-Brenda"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A unique example of Pd-catalyzed decarboxylative dehydrogenation of fully substituted N-acyl allyl enol carbonates is enabled by a new electron deficient phosphinooxazoline (PHOX) ligand. The reaction proceeds from the Z-enol carbonate to provide dehydrogenation products exclusively in high E/Z selectivity, while the E-enol carbonate provides the \u03b1-allylation product with only minor dehydrogenation. The reaction proceeds with a broad scope of Z-enol carbonates derived from N-acyl indoles to furnish acyclic formal \u03b1,\u03b2-unsaturated ester equivalents.",
"doi": "10.1016/j.tet.2019.05.065",
"pmcid": "PMC7119178",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2019-08-02",
"series_number": "31",
"volume": "75",
"issue": "31",
"pages": "4104-4109"
},
{
"id": "authors:9ah94-4xz13",
"collection": "authors",
"collection_id": "9ah94-4xz13",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190517-104313815",
"type": "article",
"title": "Palladium-catalyzed enantioselective decarboxylative allylic alkylation of fully substituted N-acyl indole-derived enol carbonates",
"author": [
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Fulton",
"given_name": "Tyler J.",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective palladium-catalyzed decarboxylative allylic alkylation of fully substituted N-acyl indole-derived enol carbonates forming acyclic all-carbon quaternary stereocenters is reported. Excellent yields up to 99% and enantioselectivities up to 98% ee are obtained through the use of a new electron-deficient phosphinoxazoline (PHOX) ligand. Control of substrate enolate geometry is crucial for high selectivity. The obtained \u03b1-quaternary N-acyl indoles are formal ester equivalents, and represent a useful handle for further synthetic transformations.",
"doi": "10.1039/c9sc01726g",
"pmcid": "PMC6566452",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2019-06-21",
"series_number": "23",
"volume": "10",
"issue": "23",
"pages": "5996-6000"
},
{
"id": "authors:2q006-eg324",
"collection": "authors",
"collection_id": "2q006-eg324",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190508-090511086",
"type": "article",
"title": "Unified Enantioselective, Convergent Synthetic Approach Toward the Furanobutenolide-Derived Polycyclic Norcembranoid Diterpenes: Synthesis of a Series of Ineleganoloids by Oxidation State Manipulation of the Carbocyclic Core",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-R-A-II"
},
{
"family_name": "Smith",
"given_name": "Russell C.",
"clpid": "Smith-R-C"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-J-L"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-A-C"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Late-stage synthetic efforts to advance the enatio- and diastereoselectively constructed [6,7,5,5]-fused tetracyclic scaffold toward the polycyclic norditerpenoid ineleganolide are disclosed. The described investigations focus on oxidation-state manipulation around the central cycloheptane ring. Computational evaluation of ground-state energies of dihydroineleganolide is used to rationalize empirical observations and provide insight for further synthetic development, enhancing the understanding of the conformational constraints of these compact polycyclic structures. Advanced synthetic manipulations generated a series of natural product-like compounds termed the ineleganoloids.",
"doi": "10.1021/acs.joc.9b00635",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2019-06-21",
"series_number": "12",
"volume": "84",
"issue": "12",
"pages": "7722-7746"
},
{
"id": "authors:9rb23-wqr28",
"collection": "authors",
"collection_id": "9rb23-wqr28",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190227-085618755",
"type": "article",
"title": "Development of a catalytic enantioselective synthesis of the guanacastepene and heptemerone tricyclic core",
"author": [
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-Andrew-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "For nearly two decades, synthetic chemists have been fascinated by the structural complexity and synthetic challenges afforded by the guanacastepene and heptemerone diterpenoids. Numerous synthetic approaches to these compounds have been reported, but to date the application of enantioselective catalysis to this problem has not been realized. Herein we report an enantioselective synthesis of an advanced intermediate corresponding to the tricyclic core common to the guanacastepenes and heptemerones. Highlights of this work include sequential Pd-catalyzed decarboxylative allylic alkylation reactions to generate the two all carbon quaternary stereocenters, the use of ring-closing metathesis to close the A ring in the presence of a distal allyl sidechain, and a regio- and diastereoselective oxidation of a trienol ether to introduce oxygenation on the A ring.",
"doi": "10.1016/j.tet.2019.02.053",
"pmcid": "PMC6959853",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2019-06-14",
"series_number": "24",
"volume": "75",
"issue": "24",
"pages": "3166-3177"
},
{
"id": "authors:dm62s-k2992",
"collection": "authors",
"collection_id": "dm62s-k2992",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190325-131628168",
"type": "article",
"title": "An unexpected Ireland\u2013Claisen rearrangement cascade during the synthesis of the tricyclic core of Curcusone C: Mechanistic elucidation by trial-and-error and automatic artificial force-induced reaction (AFIR) computations",
"author": [
{
"family_name": "Lee",
"given_name": "Chung Whan",
"clpid": "Lee-Chung-Whan"
},
{
"family_name": "Taylor",
"given_name": "Buck L. H.",
"orcid": "0000-0002-6586-3865",
"clpid": "Taylor-B-L-H"
},
{
"family_name": "Petrova",
"given_name": "Galina P.",
"clpid": "Petrova-G-P"
},
{
"family_name": "Patel",
"given_name": "Ashay",
"orcid": "0000-0001-6319-658X",
"clpid": "Patel-A"
},
{
"family_name": "Morokuma",
"given_name": "Keiji",
"clpid": "Morokuma-Keiji"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-K-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "In the course of a total synthesis effort directed toward the natural product curcusone C, the Stoltz group discovered an unexpected thermal rearrangement of a divinylcyclopropane to the product of a formal Cope/1,3-sigmatropic shift sequence. Since the involvement of a thermally forbidden 1,3-shift seemed unlikely, theoretical studies involving two approaches, the \"trial-and-error\" testing of various conceivable mechanisms (Houk group) and an \"automatic\" approach using the Maeda\u2013Morokuma AFIR method (Morokuma group) were applied to explore the mechanism. Eventually, both approaches converged on a cascade mechanism shown to have some partial literature precedent: Cope rearrangement/1,5-sigmatropic silyl shift/Claisen rearrangement/retro-Claisen rearrangement/1,5-sigmatropic silyl shift, comprising a quintet of five sequential thermally allowed pericyclic rearrangements.",
"doi": "10.1021/jacs.9b01146",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2019-05-01",
"series_number": "17",
"volume": "141",
"issue": "17",
"pages": "6995-7004"
},
{
"id": "authors:ydzb0-vp578",
"collection": "authors",
"collection_id": "ydzb0-vp578",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190903-160057854",
"type": "article",
"title": "Discussion Addendum for: The Direct Acyl-Alkylation of Arynes. Preparation of Methyl 2-(2-acetylphenyl)acetate",
"author": [
{
"family_name": "Wright",
"given_name": "Austin C.",
"clpid": "Wright-A-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "For the past 50 years, benzynes and related arynes have been a major subject of study among physical organic chemists due to their unusual electronic and structural properties. However, the utility of these strained intermediates in the domain of chemical synthesis has only relatively recently undergone a vibrant expansion. The direct insertion of aryne and heteroaryne moieties into carbon-carbon and carbon-heteroatom \u03c3 bonds presents an intriguing and unique strategy for the rapid functionalization of aryl and heteroaryl systems. Following our 2009 Organic Syntheses article on the acyl-alkylation of arynes with \u03b2-ketoesters, there have been numerous reports of related transformations involving these highly reactive intermediates. This discussion addendum is intended to document advances made in the field of (hetero)arynes since our initial disclosure. Topics covered will be divided as follows: recent methods for the acyl-functionalization of arynes, syntheses of related strained systems, applications in heterocycle synthesis, miscellaneous transformations, and strategic uses in natural product synthesis. A supplemental review on aryne insertions into \u03c3 bonds is available. Applications of arynes in transition metal catalysis will not be discussed in detail, however there are thorough reviews on the subject.",
"issn": "2333-3553",
"publisher": "Organic Syntheses, Inc.",
"publication": "Organic Syntheses",
"publication_date": "2019-04-18",
"volume": "96",
"pages": "80-97"
},
{
"id": "authors:stetw-4j690",
"collection": "authors",
"collection_id": "stetw-4j690",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190227-131909461",
"type": "article",
"title": "Cycloadditions of Oxacyclic Allenes and a Catalytic Asymmetric Entryway to Enantioenriched Cyclic Allenes",
"author": [
{
"family_name": "Yamano",
"given_name": "Michael M.",
"clpid": "Yamano-Michael-M"
},
{
"family_name": "Knapp",
"given_name": "Rachel R.",
"orcid": "0000-0003-1792-3090",
"clpid": "Knapp-Rachel-R"
},
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Ramirez",
"given_name": "Melissa",
"orcid": "0000-0002-4038-2029",
"clpid": "Ramirez-Melissa"
},
{
"family_name": "Houk",
"given_name": "Kendall N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-Kendall-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Garg",
"given_name": "Neil K.",
"orcid": "0000-0002-7793-2629",
"clpid": "Garg-Neil-K"
}
],
"abstract": "The chemistry of strained cyclic alkynes has undergone a renaissance over the past two decades. However, a related species, strained cyclic allenes, especially heterocyclic derivatives, have only recently resurfaced and represent another class of valuable intermediates. We report a mild and facile means to generate the parent 3,4\u2010oxacyclic allene from a readily accessible silyl triflate precursor, and then trap it in (4+2), (3+2), and (2+2) reactions to provide a variety of cycloadducts. In addition, we describe a catalytic, decarboxylative asymmetric allylic alkylation performed on an \u03b1\u2010silylated substrate, to ultimately permit access to an enantioenriched allene. Generation and trapping of the enantioenriched cyclic allene occurs with complete transfer of stereochemical information in a Diels\u2013Alder cycloaddition through a point\u2010chirality,\u2009axial\u2010chirality,\u2009point\u2010chirality transfer process.",
"doi": "10.1002/anie.201900503",
"pmcid": "PMC6456397",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2019-04-16",
"series_number": "17",
"volume": "58",
"issue": "17",
"pages": "5653-5657"
},
{
"id": "authors:8b514-qp356",
"collection": "authors",
"collection_id": "8b514-qp356",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190404-143251363",
"type": "book_section",
"title": "Discussion Addendum for: Preparation of (S)-tert-ButylPHOX and (S)-2-Allyl-2-Methylcyclohexanone",
"book_title": "Organic Syntheses",
"author": [
{
"family_name": "Sun",
"given_name": "Alexander W.",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "[no abstract]",
"doi": "10.1002/0471264229.os095.29",
"isbn": "9780471264224",
"publisher": "John Wiley & Sons",
"place_of_publication": "Hoboken, NJ",
"publication_date": "2019-04-02"
},
{
"id": "authors:y1kag-8n124",
"collection": "authors",
"collection_id": "y1kag-8n124",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190325-092717158",
"type": "conference_item",
"title": "Enantioselective synthesis of gem-disubstituted N-Boc diazaheterocycles via decarboxylative asymmetric allylic alkylation",
"author": [
{
"family_name": "Sun",
"given_name": "Alexander",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Stoltz",
"given_name": "Brian Mark",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective synthesis of diverse N4-Boc-protected a,a-disubstituted piperazin-2-ones using the\npalladiumcatalyzed decarboxylative allylic alkylation reaction has been achieved. Using a chiral Pd-catalyst derived from\nan electron deficient PHOX ligand, chiral piperazinones are synthesized in high yields and enantioselectivity. The chiral\npiperazinone products can be deprotected and reduced to valuable gem-disubstituted piperazines. This reaction is\nfurther extended to enable the enantioselective synthesis of a,a-disubstituted tetrahydropyrimidin-2-ones, which are\nhydrolyzed into corresponding chiral b2,2-amino acids.",
"publisher": "Caltech Library",
"publication_date": "2019-04"
},
{
"id": "authors:sbjxc-q1k69",
"collection": "authors",
"collection_id": "sbjxc-q1k69",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190124-110425627",
"type": "article",
"title": "Palladium-Catalyzed Construction of Quaternary Stereocenters by Enantioselective Arylation of \u03b3-Lactams with Aryl Chlorides and Bromides",
"author": [
{
"family_name": "Jette",
"given_name": "Carina I.",
"orcid": "0000-0002-8476-6032",
"clpid": "Jette-C-I"
},
{
"family_name": "Geibel",
"given_name": "Irina",
"clpid": "Geibel-I"
},
{
"family_name": "Bachman",
"given_name": "Shoshana",
"clpid": "Bachman-S"
},
{
"family_name": "Hayashi",
"given_name": "Masaki",
"clpid": "Hayashi-Masaki"
},
{
"family_name": "Sakurai",
"given_name": "Shunya",
"clpid": "Sakurai-Shunya"
},
{
"family_name": "Shimizu",
"given_name": "Hideki",
"clpid": "Shimizu-Hideki"
},
{
"family_name": "Morgan",
"given_name": "Jeremy B.",
"clpid": "Morgan-J-B"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein, we report the first Pd\u2010catalyzed enantioselective arylation of \u03b1\u2010substituted \u03b3\u2010lactams. Two sets of conditions were developed for this transformation, allowing for the use of either aryl chlorides or bromides as electrophiles. Utilizing a highly electron\u2010rich, dialkylphosphine ligand, we have been able to construct \u03b1\u2010quaternary centers in good yields (up to 91% yield) and high enantioselectivities (up to 97% ee).",
"doi": "10.1002/anie.201814475",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2019-03-22",
"series_number": "13",
"volume": "58",
"issue": "13",
"pages": "4297-4301"
},
{
"id": "authors:x8vdb-tvm32",
"collection": "authors",
"collection_id": "x8vdb-tvm32",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181113-112609134",
"type": "article",
"title": "Atroposelective Synthesis of PINAP via Dynamic Kinetic Asymmetric Transformation",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Bhat",
"given_name": "Vikram",
"orcid": "0000-0001-5621-5121",
"clpid": "Bhat-V"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
}
],
"abstract": "The atroposelective synthesis of PINAP ligands has been accomplished via a palladium\u2010catalyzed C\u2212P coupling process through dynamic kinetic asymmetric transformation. These catalytic conditions allow access to a wide variety of alkoxy\u2010 and benzyloxy\u2010substituted PINAP ligands in high enantiomeric excess. The methods described in this communication afford valuable P,N ligands in good yields and high enantioselectivity using low catalyst loading.",
"doi": "10.1002/adsc.201801248",
"issn": "1615-4150",
"publisher": "Wiley",
"publication": "Advanced Synthesis and Catalysis",
"publication_date": "2019-02-01",
"series_number": "3",
"volume": "361",
"issue": "3",
"pages": "441-444"
},
{
"id": "authors:fv6tw-7t802",
"collection": "authors",
"collection_id": "fv6tw-7t802",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181106-111914131",
"type": "article",
"title": "Enantioselective synthesis of gem-disubstituted N-Boc diazaheterocycles via decarboxylative asymmetric allylic alkylation",
"author": [
{
"family_name": "Sun",
"given_name": "Alexander W.",
"orcid": "0000-0001-6639-4469",
"clpid": "Sun-Alexander-W"
},
{
"family_name": "Hess",
"given_name": "Stephan N.",
"clpid": "Hess-Stephan-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective synthesis of diverse N4-Boc-protected \u03b1,\u03b1-disubstituted piperazin-2-ones using the palladium-catalyzed decarboxylative allylic alkylation reaction has been achieved. Using a chiral Pd-catalyst derived from an electron deficient PHOX ligand, chiral piperazinones are synthesized in high yields and enantioselectivity. The chiral piperazinone products can be deprotected and reduced to valuable gem-disubstituted piperazines. This reaction is further extended to enable the enantioselective synthesis of \u03b1,\u03b1-disubstituted tetrahydropyrimidin-2-ones, which are hydrolyzed into corresponding chiral \u03b2^(2,2)-amino acids.",
"doi": "10.1039/c8sc03967d",
"pmcid": "PMC6345351",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2019-01-21",
"series_number": "3",
"volume": "10",
"issue": "3",
"pages": "788-792"
},
{
"id": "authors:r8k7p-qgz90",
"collection": "authors",
"collection_id": "r8k7p-qgz90",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181221-091725806",
"type": "article",
"title": "Concise total syntheses of (\u2013)-jorunnamycin A and (\u2013)-jorumycin enabled by asymmetric catalysis",
"author": [
{
"family_name": "Welin",
"given_name": "Eric R.",
"orcid": "0000-0002-1760-4121",
"clpid": "Welin-Eric-R"
},
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Klatte",
"given_name": "Max",
"clpid": "Klatte-Max"
},
{
"family_name": "Lapointe",
"given_name": "Guillaume",
"clpid": "Lapointe-Guillaume"
},
{
"family_name": "Pototschnig",
"given_name": "Gerit M.",
"clpid": "Pototschnig-Gerit-M"
},
{
"family_name": "McDermott",
"given_name": "Martina S. J.",
"clpid": "McDermott-Martina-S-J"
},
{
"family_name": "Conklin",
"given_name": "Dylan",
"orcid": "0000-0003-4708-0071",
"clpid": "Conklin-Dylan"
},
{
"family_name": "Gilmore",
"given_name": "Christopher D.",
"clpid": "Gilmore-Christopher-D"
},
{
"family_name": "Tadross",
"given_name": "Pamela M.",
"clpid": "Tadross-Pamela-M"
},
{
"family_name": "Haley",
"given_name": "Christopher K.",
"clpid": "Haley-Christopher-K"
},
{
"family_name": "Negoro",
"given_name": "Kenji",
"orcid": "0000-0002-8341-5089",
"clpid": "Negoro-Kenji"
},
{
"family_name": "Glibstrup",
"given_name": "Emil",
"orcid": "0000-0002-9060-6270",
"clpid": "Glibstrup-Emil"
},
{
"family_name": "Gr\u00fcnanger",
"given_name": "Christian U.",
"clpid": "Gr\u00fcnanger-Christian-U"
},
{
"family_name": "Allan",
"given_name": "Kevin M.",
"orcid": "0000-0002-7750-3621",
"clpid": "Allan-Kevin-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Slamon",
"given_name": "Dennis J.",
"orcid": "0000-0002-6330-498X",
"clpid": "Slamon-Dennis-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The bis-tetrahydroisoquinoline (bis-THIQ) natural products have been studied intensively over the past four decades for their exceptionally potent anticancer activity, in addition to strong gram-positive and -negative antibiotic character. Synthetic strategies toward these complex polycyclic compounds have relied heavily on electrophilic aromatic chemistry, such as the Pictet-Spengler reaction, that mimics their biosynthetic pathways. Herein we report an approach to two bis-THIQ natural products, jorunnamycin A and jorumycin, that instead harnesses the power of modern transition-metal catalysis for the three major bond-forming events and proceeds with high efficiency (15 and 16 steps, respectively). By breaking from biomimicry, this strategy allows for the preparation of a more diverse set of non-natural analogs.",
"doi": "10.1126/science.aav3421",
"pmcid": "PMC7017906",
"issn": "0036-8075",
"publisher": "American Association for the Advancement of Science",
"publication": "Science",
"publication_date": "2019-01-18",
"series_number": "6424",
"volume": "363",
"issue": "6424",
"pages": "270-275"
},
{
"id": "authors:g74pq-te194",
"collection": "authors",
"collection_id": "g74pq-te194",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-080428895",
"type": "article",
"title": "Intramolecular Hydrogen Shift Chemistry of Hydroperoxy-Substituted Peroxy Radicals",
"author": [
{
"family_name": "Praske",
"given_name": "Eric",
"orcid": "0000-0001-7169-4423",
"clpid": "Praske-E"
},
{
"family_name": "Otkj\u00e6r",
"given_name": "Rasmus V.",
"orcid": "0000-0002-6094-1828",
"clpid": "Otkj\u00e6r-R-V"
},
{
"family_name": "Crounse",
"given_name": "John D.",
"orcid": "0000-0001-5443-729X",
"clpid": "Crounse-J-D"
},
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Kjaergaard",
"given_name": "Henrik G.",
"orcid": "0000-0002-7275-8297",
"clpid": "Kjaergaard-H-G"
},
{
"family_name": "Wennberg",
"given_name": "Paul O.",
"orcid": "0000-0002-6126-3854",
"clpid": "Wennberg-P-O"
}
],
"abstract": "Gas-phase autoxidation \u2013 the sequential regeneration of peroxy radicals (RO_2) via intramolecular hydrogen shifts (H-shifts) followed by oxygen addition \u2013 leads to the formation of organic hydroperoxides. The atmospheric fate of these peroxides remains unclear, including the potential for further H-shift chemistry. Here, we report H-shift rate coefficients for a system of RO_2 with hydroperoxide functionality produced in the OH-initiated oxidation of 2-hydroperoxy-2-methylpentane. The initial RO_2 formed in this chemistry are unable to undergo \u03b1-OOH H-shift (HOOC\u2013H) reactions. However, these RO_2 rapidly isomerize (>100 s^(\u20131) at 296 K) by H-shift of the hydroperoxy hydrogen (ROO\u2013H) to produce a hydroperoxy-substituted RO_2 with an accessible \u03b1-OOH hydrogen. First order rate coefficients for the 1,5 H-shift of the \u03b1-OOH hydrogen are measured to be \u223c0.04 s^(\u20131) (296 K) and \u223c0.1 s^(\u20131) (318 K), within 50% of the rate coefficients calculated using multiconformer transition state theory. Reaction of the RO_2 with NO produces alkoxy radicals which also undergo rapid isomerization via 1,6 and 1,5 H-shift of the hydroperoxy hydrogen (ROO\u2013H) to produce RO_2 with alcohol functionality. One of these hydroxy-substituted RO_2 exhibits a 1,5 \u03b1-OH (HOC\u2013H) H-shift, measured to be \u223c0.2 s^(\u20131) (296 K) and \u223c0.6 s^(\u20131) (318 K), again in agreement with the calculated rates. Thus, the rapid shift of hydroperoxy hydrogens in alkoxy and peroxy radicals enables intramolecular reactions that would otherwise be inaccessible.",
"doi": "10.1021/acs.jpca.8b09745",
"issn": "1089-5639",
"publisher": "American Chemical Society",
"publication": "Journal of Physical Chemistry A",
"publication_date": "2019-01-17",
"series_number": "2",
"volume": "123",
"issue": "2",
"pages": "590-600"
},
{
"id": "authors:4fs3s-m8839",
"collection": "authors",
"collection_id": "4fs3s-m8839",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181212-100802379",
"type": "article",
"title": "Concise Syntheses of \u0394^(12)-Prostaglandin J Natural Products via Stereoretentive Metathesis",
"author": [
{
"family_name": "Li",
"given_name": "Jiaming",
"orcid": "0000-0001-6646-5693",
"clpid": "Li-Jiaming"
},
{
"family_name": "Ahmed",
"given_name": "Tonia S.",
"clpid": "Ahmed-T-S"
},
{
"family_name": "Xu",
"given_name": "Chen",
"orcid": "0000-0002-3222-459X",
"clpid": "Xu-Chen"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "\u0394^(12)-Prostaglandin J family is recently discovered and has potent anticancer activity. Concise syntheses of four \u0394^(12)-prostaglandin J natural products (7\u20138 steps in the longest linear sequences) are reported, enabled by convergent stereoretentive cross-metathesis. Exceptional control of alkene geometry was achieved through stereoretention.",
"doi": "10.1021/jacs.8b12816",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2019-01-09",
"series_number": "1",
"volume": "141",
"issue": "1",
"pages": "154-158"
},
{
"id": "authors:mv6za-hrj72",
"collection": "authors",
"collection_id": "mv6za-hrj72",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181205-140604109",
"type": "article",
"title": "Intermolecular Stereoselective Iridium-Catalyzed Allylic \n Alkylation: An Evolutionary Account",
"author": [
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Our lab has long been interested in the development of methods for the creation of enantioenriched all-carbon quaternary stereocenters. Historically, our interest has centered on palladium-catalyzed allylic alkylation, though recent efforts have moved to include the study of iridium catalysts. Whereas palladium catalysts enable the preparation of isolated stereocenters, the use of iridium catalysts allows for the direct construction of vicinal stereocenters via an enantio-, diastereo-, and regioselective allylic alkylation. This Account details the evolution of our research program from inception, which focused on the first iridium-catalyzed allylic alkylation to prepare stereodyads containing a single quaternary stereocenter, to our most recent discovery that allows for the synthesis of vicinal quaternary centers.",
"doi": "10.1055/s-0037-1610217",
"pmcid": "PMC6870865",
"issn": "0936-5214",
"publisher": "Georg Thieme Verlag",
"publication": "Synlett",
"publication_date": "2018-12",
"series_number": "19",
"volume": "29",
"issue": "19",
"pages": "2481-2492"
},
{
"id": "authors:ekq04-kwh06",
"collection": "authors",
"collection_id": "ekq04-kwh06",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181101-140146236",
"type": "article",
"title": "The CryoEM Method MicroED as a Powerful Tool for Small Molecule Structure Determination",
"author": [
{
"family_name": "Jones",
"given_name": "Christopher G.",
"clpid": "Jones-Christopher-G"
},
{
"family_name": "Martynowycz",
"given_name": "Michael W.",
"orcid": "0000-0003-0055-230X",
"clpid": "Martynowycz-Michael-W"
},
{
"family_name": "Hattne",
"given_name": "Johan",
"clpid": "Hattne-Johan"
},
{
"family_name": "Fulton",
"given_name": "Tyler",
"orcid": "0000-0002-9343-2456",
"clpid": "Fulton-Tyler-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Rodriguez",
"given_name": "Jose A.",
"clpid": "Rodriguez-Jose-A"
},
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Gonen",
"given_name": "Tamir",
"orcid": "0000-0002-9254-4069",
"clpid": "Gonen-Tamir"
}
],
"abstract": "In the many scientific endeavors that are driven by organic chemistry, unambiguous identification of small molecules is of paramount importance. Over the past 50 years, NMR and other powerful spectroscopic techniques have been developed to address this challenge. While almost all of these techniques rely on inference of connectivity, the unambiguous determination of a small molecule's structure requires X-ray and/or neutron diffraction studies. In practice, however, X-ray crystallography is rarely applied in routine organic chemistry due to intrinsic limitations of both the analytes and the technique. Here we report the use of the electron cryo-microscopy (cryoEM) method microcrystal electron diffraction (MicroED) to provide routine and unambiguous structural determination of small organic molecules. From simple powders, with minimal sample preparation, we could collect high-quality MicroED data from nanocrystals (\u223c100 nm, \u223c10^(\u201315) g) resulting in atomic resolution (<1 \u00c5) crystal structures in minutes.",
"doi": "10.1021/acscentsci.8b00760",
"pmcid": "PMC6276044",
"issn": "2374-7943",
"publisher": "American Chemical Society",
"publication": "ACS Central Science",
"publication_date": "2018-11-28",
"series_number": "11",
"volume": "4",
"issue": "11",
"pages": "1587-1592"
},
{
"id": "authors:n0a0d-bkn18",
"collection": "authors",
"collection_id": "n0a0d-bkn18",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181029-094838158",
"type": "article",
"title": "New directions in natural product synthesis",
"author": [
{
"family_name": "Davies",
"given_name": "Huw M. L.",
"orcid": "0000-0001-6254-9398",
"clpid": "Davies-H-M-L"
},
{
"family_name": "Itami",
"given_name": "Kenichiro",
"clpid": "Itami-Kenichiro"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Research in the total synthesis of natural products has changed considerably in recent years. Much of the research effort has moved away from only focusing on the synthesis of a specific natural product, and instead toward the development of general synthetic strategies that enable the synthesis of a broad family of natural products. The new approach offers considerable advantages because the new synthetic strategies are often very flexible and thus, can have lasting influence on the field of organic synthesis. This thematic issue highlights several of the recently developed synthetic strategies and illustrates their flexibility for the synthesis of complex natural products. The thematic issue also includes reviews on visual algorithms to compare the efficiency of different total syntheses and computational approaches that can assist in the design of new total synthesis approaches.",
"doi": "10.1039/c8cs90115e",
"issn": "0306-0012",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Society Reviews",
"publication_date": "2018-11-07",
"series_number": "21",
"volume": "47",
"issue": "21",
"pages": "7828-7829"
},
{
"id": "authors:8avbe-9d296",
"collection": "authors",
"collection_id": "8avbe-9d296",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180917-125103681",
"type": "article",
"title": "Catalyst-Controlled Selective Functionalization of Unactivated C\u2013H Bonds in the Presence of Electronically Activated C\u2013H Bonds",
"author": [
{
"family_name": "Liu",
"given_name": "Wenbin",
"orcid": "0000-0001-8854-8174",
"clpid": "Liu-Wenbin"
},
{
"family_name": "Ren",
"given_name": "Zhi",
"orcid": "0000-0001-9812-0251",
"clpid": "Ren-Zhi"
},
{
"family_name": "Bosse",
"given_name": "Aaron T.",
"clpid": "Bosse-A-T"
},
{
"family_name": "Liao",
"given_name": "Kuangbiao",
"clpid": "Liao-Kuangbiao"
},
{
"family_name": "Goldstein",
"given_name": "Elizabeth L.",
"clpid": "Goldstein-E-L"
},
{
"family_name": "Bacsa",
"given_name": "John",
"clpid": "Bacsa-J"
},
{
"family_name": "Musaev",
"given_name": "Djamaladdin G.",
"orcid": "0000-0003-1160-6131",
"clpid": "Musaev-D-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Davies",
"given_name": "Huw M. L.",
"orcid": "0000-0001-6254-9398",
"clpid": "Davies-H-M-L"
}
],
"abstract": "A new chiral dirhodium tetracarboxylate catalyst, Rh_2(S-2-Cl-5-BrTPCP)_4, has been developed for C\u2013H functionalization reactions by means of donor/acceptor carbene intermediates. The dirhodium catalyst contains four (S)-1-(2-chloro-5-bromophenyl)-2,2-diphenylcyclopropane-1-carboxylate ligands, in which all four 2-chloro-5-bromophenyl groups are on the same face of the catalyst, leading to a structure, which is close to C_4 symmetric. The catalyst induces highly site selective functionalization of remote, unactivated methylene C\u2013H bonds even in the presence of electronically activated benzylic C\u2013H bonds, which are typically favored using earlier established dirhodium catalysts, and the reactions proceed with high levels of diastereo- and enantioselectivity. This C\u2013H functionalization method is applicable to a variety of aryl and heteroaryl derivatives. Furthermore, the potential of this methodology was illustrated by sequential C\u2013H functionalization reactions to access the macrocyclic core of the cylindrocyclophane class of natural products.",
"doi": "10.1021/jacs.8b07534",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2018-09-26",
"series_number": "38",
"volume": "140",
"issue": "38",
"pages": "12247-12255"
},
{
"id": "authors:69kfm-xfv27",
"collection": "authors",
"collection_id": "69kfm-xfv27",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180905-091810349",
"type": "article",
"title": "Palladium-Catalyzed Enantioselective C_(sp)^3\u2013C_(sp)^3 Cross-Coupling for the Synthesis of (Poly)fluorinated Chiral Building Blocks",
"author": [
{
"family_name": "Lu",
"given_name": "Yanhui",
"clpid": "Lu-Yanhui"
},
{
"family_name": "Goldstein",
"given_name": "Elizabeth L.",
"clpid": "Goldstein-Elizabeth-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A general method for the enantioselective synthesis of carbo- and heterocyclic carbonyl compounds bearing fluorinated \u03b1-tetrasubstituted stereocenters using palladium-catalyzed decarboxylative allylic alkylation is described. The stereoselective C_(sp)^3\u2013C_(sp)^3 cross-coupling reaction delivers five- and six-membered ketone and lactam products bearing (poly)fluorinated tetrasubstituted chiral centers in high yields and enantioselectivities. These fluorinated, stereochemically rich building blocks hold potential value in medicinal chemistry and are prepared using an orthogonal and enantioselective approach into such chiral moieties compared to traditional approaches, often without the use of electrophilic fluorinating reagents.",
"doi": "10.1021/acs.orglett.8b02369",
"pmcid": "PMC6192028",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2018-09-21",
"series_number": "18",
"volume": "20",
"issue": "18",
"pages": "5657-5660"
},
{
"id": "authors:0267d-1kd39",
"collection": "authors",
"collection_id": "0267d-1kd39",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180806-125449354",
"type": "article",
"title": "General and Practical Potassium Methoxide/Disilane-Mediated Dehalogenative Deuteration of (Hetero)Arylhalides",
"author": [
{
"family_name": "Wang",
"given_name": "Xin",
"orcid": "0000-0002-6180-0058",
"clpid": "Wang-Xin"
},
{
"family_name": "Zhu",
"given_name": "Ming-Hui",
"clpid": "Zhu-Ming-Hui"
},
{
"family_name": "Schuman",
"given_name": "David P.",
"clpid": "Schuman-D-P"
},
{
"family_name": "Zhong",
"given_name": "Dayou",
"clpid": "Zhong-Dayou"
},
{
"family_name": "Wang",
"given_name": "Wen-Yan",
"clpid": "Wang-Wen-Yan"
},
{
"family_name": "Wu",
"given_name": "Lin-Yang",
"clpid": "Wu-Lin-Yang"
},
{
"family_name": "Liu",
"given_name": "Wei",
"orcid": "0000-0001-6249-3179",
"clpid": "Liu-Wei-Chemistry"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
}
],
"abstract": "Herein we describe a general, mild and scalable method for deuterium incorporation by potassium methoxide/hexamethyldisilane-mediated dehalogenation of arylhalides. With CD3CN as a deuterium source, a wide array of heteroarenes prevalent in pharmaceuticals and bearing diverse functional groups are labeled with excellent deuterium incorporation (>60 examples). The ipso-selectivity of this method provides precise access to libraries of deuterated indoles and quinolines. The synthetic utility of our method has been demonstrated by the incorporation of deuterium into complex natural and drug-like compounds.",
"doi": "10.1021/jacs.8b07597",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2018-09-05",
"series_number": "35",
"volume": "140",
"issue": "35",
"pages": "10970-10974"
},
{
"id": "authors:r8g7f-74s61",
"collection": "authors",
"collection_id": "r8g7f-74s61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180727-091530074",
"type": "article",
"title": "Catalytic Enantioselective Synthesis of Acyclic Quaternary Centers: Palladium-Catalyzed Decarboxylative Allylic Alkylation of Fully Substituted Acyclic Enol Carbonates",
"author": [
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective palladium-catalyzed decarboxylative allylic alkylation of fully substituted acyclic enol carbonates providing linear \u03b1-quaternary ketones is reported. Investigation into the reaction revealed that the use of an electron-deficient phosphinooxazoline ligand renders the enolate geometry of the starting material inconsequential, with the same enantiomer of product obtained in the same level of selectivity regardless of the starting ratio of enolates. As a result, a general method toward acyclic all-carbon quaternary stereocenters has been developed.",
"doi": "10.1021/jacs.8b05560",
"pmcid": "PMC6103296",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2018-08-15",
"series_number": "32",
"volume": "140",
"issue": "32",
"pages": "10109-10112"
},
{
"id": "authors:vvy23-j9468",
"collection": "authors",
"collection_id": "vvy23-j9468",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180803-132305205",
"type": "article",
"title": "Synergistic O\u2083 + OH oxidation pathway to extremely low-volatility dimers revealed in \u03b2-pinene secondary organic aerosol",
"author": [
{
"family_name": "Kenseth",
"given_name": "Christopher M.",
"orcid": "0000-0003-3188-2336",
"clpid": "Kenseth-Christopher-M"
},
{
"family_name": "Huang",
"given_name": "Yuanlong",
"orcid": "0000-0002-6726-8904",
"clpid": "Huang-Yuanlong"
},
{
"family_name": "Zhao",
"given_name": "Ran",
"orcid": "0000-0002-1096-7632",
"clpid": "Zhao-Ran"
},
{
"family_name": "Dalleska",
"given_name": "Nathan F.",
"orcid": "0000-0002-2059-1587",
"clpid": "Dalleska-Nathan-F"
},
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Seinfeld",
"given_name": "John H.",
"orcid": "0000-0003-1344-4068",
"clpid": "Seinfeld-J-H"
}
],
"abstract": "Dimeric compounds contribute significantly to the formation and growth of atmospheric secondary organic aerosol (SOA) derived from monoterpene oxidation. However, the mechanisms of dimer production, in particular the relevance of gas- vs. particle-phase chemistry, remain unclear. Here, through a combination of mass spectrometric, chromatographic, and synthetic techniques, we identify a suite of dimeric compounds (C_(15\u201319)H_(24\u201332)O_(5\u201311)) formed from concerted O\u2083 and OH oxidation of \u03b2-pinene (i.e., accretion of O\u2083- and OH-derived products/intermediates). These dimers account for an appreciable fraction (5.9\u201325.4%) of the \u03b2-pinene SOA mass and are designated as extremely low-volatility organic compounds. Certain dimers, characterized as covalent dimer esters, are conclusively shown to form through heterogeneous chemistry, while evidence of dimer production via gas-phase reactions is also presented. The formation of dimers through synergistic O\u2083 + OH oxidation represents a potentially significant, heretofore-unidentified source of low-volatility monoterpene SOA. This reactivity also suggests that the current treatment of SOA formation as a sum of products originating from the isolated oxidation of individual precursors fails to accurately reflect the complexity of oxidation pathways at play in the real atmosphere. Accounting for the role of synergistic oxidation in ambient SOA formation could help to resolve the discrepancy between the measured atmospheric burden of SOA and that predicted by regional air quality and global climate models.",
"doi": "10.1073/pnas.1804671115",
"pmcid": "PMC6099901",
"issn": "0027-8424",
"publisher": "National Academy of Sciences",
"publication": "Proceedings of the National Academy of Sciences of the United States of America",
"publication_date": "2018-08-14",
"series_number": "33",
"volume": "115",
"issue": "33",
"pages": "8301-8306"
},
{
"id": "authors:e6186-a2280",
"collection": "authors",
"collection_id": "e6186-a2280",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181108-143733231",
"type": "conference_item",
"title": "Cyclic alkanes transfer dehydrogenation using homogeneous iridium pincer catalysts",
"author": [
{
"family_name": "Al Saihati",
"given_name": "Zainab",
"orcid": "0000-0002-3837-9736",
"clpid": "Al-Saihati-Z"
},
{
"family_name": "Haibach",
"given_name": "Michael C.",
"orcid": "0000-0001-8383-5633",
"clpid": "Haibach-M-C"
},
{
"family_name": "Swisher",
"given_name": "Nicholas A.",
"orcid": "0000-0002-5320-407X",
"clpid": "Swisher-N-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "Described herein is a method for the transfer dehydrogenation of cyclic alkanes to alkenes and aroms. using synthesized homogeneous iridium pincer complexes and H_2 acceptor. This method is a promising alternative for the industrial energy intensive dehydrogenation process as iridium pincer catalysts have greater selectivity relative to heterogeneous catalysts and require significantly lower reaction temps.",
"publisher": "Caltech Library",
"publication_date": "2018-08"
},
{
"id": "authors:8t5sq-3hq12",
"collection": "authors",
"collection_id": "8t5sq-3hq12",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180730-120150815",
"type": "article",
"title": "Short Enantioselective Formal Synthesis of (\u2013)-Platencin",
"author": [
{
"family_name": "Defieber",
"given_name": "Christian",
"clpid": "Defieber-Christian"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-Justin-T"
},
{
"family_name": "Grabovyl",
"given_name": "Gennadii A.",
"clpid": "Grabovyl-Gennadii-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A short enantioselective formal synthesis of the antibiotic natural product platencin is reported. Key steps in the synthesis include enantioselective decarboxylation alkylation, aldehyde/olefin radical cyclization, and regioselective aldol cyclization.",
"doi": "10.1055/s-0037-1610437",
"pmcid": "PMC6498846",
"issn": "0039-7881",
"publisher": "Georg Thieme Verlag",
"publication": "Synthesis-Stuttgart",
"publication_date": "2018-07-27",
"series_number": "22",
"volume": "50",
"issue": "22",
"pages": "4359-4368"
},
{
"id": "authors:eesgy-zwc88",
"collection": "authors",
"collection_id": "eesgy-zwc88",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180611-142236882",
"type": "article",
"title": "Total Synthesis of the Norhasubanan Alkaloid Stephadiamine",
"author": [
{
"family_name": "Hartrampf",
"given_name": "Nina",
"orcid": "0000-0003-0875-6390",
"clpid": "Hartrampf-Nina"
},
{
"family_name": "Winter",
"given_name": "Nils",
"clpid": "Winter-Nils"
},
{
"family_name": "Pupo",
"given_name": "Gabriele",
"orcid": "0000-0003-3084-3888",
"clpid": "Pupo-Gabriele"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Trauner",
"given_name": "Dirk",
"orcid": "0000-0002-6782-6056",
"clpid": "Trauner-Dirk"
}
],
"abstract": "(+)-Stephadiamine is an unusual alkaloid isolated from the vine Stephania japonica. It features a norhasubanan skeleton, and contains two adjacent \u03b1-tertiary amines, which renders it an attractive synthetic target. Here, we present the first total synthesis of stephadiamine, which hinges on an efficient cascade reaction to implement the aza[4.3.3]propellane core of the alkaloid. The \u03b1-aminolactone moiety in a highly hindered position was installed via Tollens reaction and Curtius rearrangement. Useful building blocks for the asymmetric synthesis of morphine and (nor)hasubanan alkaloids are introduced.",
"doi": "10.1021/jacs.8b01918",
"pmcid": "PMC6130314",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2018-07-18",
"series_number": "28",
"volume": "140",
"issue": "28",
"pages": "8675-8680"
},
{
"id": "authors:ery4y-30784",
"collection": "authors",
"collection_id": "ery4y-30784",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180514-112203501",
"type": "article",
"title": "Enantioselective Synthesis of Vicinal All-Carbon Quaternary Centers via Iridium-Catalyzed Allylic Alkylation",
"author": [
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development of the first enantioselective transition\u2010metal\u2010catalyzed allylic alkylation providing access to acyclic products bearing vicinal all\u2010carbon quaternary centers is disclosed. The iridium\u2010catalyzed allylic alkylation reaction proceeds with excellent yields and selectivities for a range of malononitrile\u2010derived nucleophiles and trisubstituted allylic electrophiles. The utility of these sterically congested products is explored through a series of diverse chemo\u2010 and diastereoselective product transformations to afford a number of highly valuable, densely functionalized building blocks, including those containing vicinal all\u2010carbon quaternary stereocenters.",
"doi": "10.1002/anie.201804820",
"pmcid": "PMC6033654",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2018-07-09",
"series_number": "28",
"volume": "57",
"issue": "28",
"pages": "8664-8667"
},
{
"id": "authors:kx9bc-tkt04",
"collection": "authors",
"collection_id": "kx9bc-tkt04",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180104-140230299",
"type": "article",
"title": "Wolff/Cope Approach to the AB Ring of the Sesterterpenoid Variecolin",
"author": [
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-Michael-R"
},
{
"family_name": "Henry",
"given_name": "Christopher E.",
"clpid": "Henry-Christopher-E"
},
{
"family_name": "Jensen",
"given_name": "Thomas",
"clpid": "Jensen-Thomas"
},
{
"family_name": "Wu",
"given_name": "Kun-Liang (Phil)",
"clpid": "Wu-Kun-Liang-Phil"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A stereoselective synthesis of the AB ring of the complex sesterterpenoid variecolin is presented. Our strategy features the development of a tandem Wolff/Cope rearrangement of \u03b1-diazo cyclobutyl ketones for the construction of fused, 8-membered carbocycles. Preliminary studies revealed a facile Wolff rearrangement but a difficult vinyl ketene cyclobutane Cope rearrangement. We have leveraged an efficient microwave-promoted tandem rearrangement to prepare the desired functionalized cyclooctadienones that we envision as potential key intermediates in the convergent synthesis of variecolin.",
"doi": "10.1021/acs.joc.7b02972",
"pmcid": "PMC6035096",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2018-07-06",
"series_number": "13",
"volume": "83",
"issue": "13",
"pages": "6995-7009"
},
{
"id": "authors:64jrb-sve82",
"collection": "authors",
"collection_id": "64jrb-sve82",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180416-135313177",
"type": "article",
"title": "Enantioselective palladium-catalyzed allylic alkylation reactions in the synthesis of Aspidosperma and structurally related monoterpene indole alkaloids",
"author": [
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Enantioselective Pd-catalyzed allylic alkylations of prochiral enolates represent a powerful tool for the construction of all-carbon quaternary stereocenters. This review describes the emergence of such reactions as strategic linchpins that enable efficient, stereocontrolled syntheses of Aspidosperma and related monoterpene indole alkaloids.",
"doi": "10.1039/c7np00069c",
"pmcid": "PMC6013405",
"issn": "0265-0568",
"publisher": "Royal Society of Chemistry",
"publication": "Natural Product Reports",
"publication_date": "2018-06-01",
"series_number": "6",
"volume": "35",
"issue": "6",
"pages": "559-574"
},
{
"id": "authors:cgekk-m0318",
"collection": "authors",
"collection_id": "cgekk-m0318",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180327-133635374",
"type": "article",
"title": "Development of a Unified Enantioselective, Convergent Synthetic Approach Toward the Furanobutenolide-Derived Polycyclic Norcembranoid Diterpenes: Asymmetric Formation of the Polycyclic Norditerpenoid Carbocyclic Core by Tandem Annulation Cascade",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Smith",
"given_name": "Russell C.",
"clpid": "Smith-Russell-C"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-Jennifer-L"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-Amanda-C"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective and diastereoselective approach toward the synthesis of the tetracyclic scaffold of the furanobutenolide-derived polycyclic norditerpenoids is described. Focusing on synthetic efforts toward ineleganolide, the synthetic approach utilizes a palladium-catalyzed enantioselective allylic alkylation for the construction of the requisite chiral tertiary ether. A diastereoselective cyclopropanation\u2013Cope rearrangement cascade enabled the convergent assembly of the ineleganolide [6,7,5,5]-tetracyclic scaffold. Investigation of substrates for this critical tandem annulation process is discussed along with synthetic manipulations of the [6,7,5,5]-tetracyclic scaffold and the attempted interconversion of the [6,7,5,5]-tetracyclic scaffold of ineleganolide to the isomeric [7,6,5,5]-core of scabrolide A and its naturally occurring isomers. Computational evaluation of ground-state energies of late-stage synthetic intermediates was used to guide synthetic development and aid in the investigation of the conformational rigidity of these highly constrained and compact polycyclic structures.",
"doi": "10.1021/acs.joc.7b02825",
"pmcid": "PMC5889334",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2018-04-06",
"series_number": "7",
"volume": "83",
"issue": "7",
"pages": "3467-3485"
},
{
"id": "authors:8y5wp-aw879",
"collection": "authors",
"collection_id": "8y5wp-aw879",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180109-144403638",
"type": "article",
"title": "The Cyanthiwigin Natural Product Core as a Complex Molecular Scaffold for Comparative Late-Stage C\u2013H Functionalization Studies",
"author": [
{
"family_name": "Kim",
"given_name": "Kelly E.",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Adams",
"given_name": "Ashley M.",
"orcid": "0000-0003-0823-3709",
"clpid": "Adams-Ashley-M"
},
{
"family_name": "Chiappini",
"given_name": "Nicholas D.",
"orcid": "0000-0003-0469-1008",
"clpid": "Chiappini-N-D"
},
{
"family_name": "Du Bois",
"given_name": "J.",
"orcid": "0000-0001-7847-1548",
"clpid": "Du-Bois-Justin"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The desire for maximally efficient transformations in complex molecule synthesis has contributed to a surge of interest in C\u2013H functionalization methods development in recent years. In contrast to the steady stream of methodological reports, however, there are noticeably fewer studies comparing the efficacies of different C\u2013H functionalization protocols on a single structurally intricate substrate. Recognizing the importance of heteroatom incorporation in complex molecule synthesis, this report discloses a comparative examination of diverse strategies for C\u2013O, C\u2013N, and C\u2013X bond formation through late-stage C\u2013H oxidation of the tricyclic cyanthiwigin natural product core. Methods for allylic C\u2013H acetoxylation, tertiary C\u2013H hydroxylation, tertiary C\u2013H amination, tertiary C\u2013H azidation, and secondary C\u2013H halogenation are explored. These efforts highlight the robustness and selectivities of many well-established protocols for C\u2013H oxidation when applied to a complex molecular framework, and the findings are relevant to chemists aiming to employ such strategies in the context of chemical synthesis.",
"doi": "10.1021/acs.joc.7b03291",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2018-03-16",
"series_number": "6",
"volume": "83",
"issue": "6",
"pages": "3023-3033"
},
{
"id": "authors:cwj0g-79p25",
"collection": "authors",
"collection_id": "cwj0g-79p25",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180207-083556564",
"type": "article",
"title": "Nickel-catalyzed enantioselective allylic alkylation of lactones and lactams with unactivated allylic alcohols",
"author": [
{
"family_name": "Ngamnithiporn",
"given_name": "Aurapat",
"orcid": "0000-0002-5389-8171",
"clpid": "Ngamnithiporn-Aurapat"
},
{
"family_name": "Jette",
"given_name": "Carina I.",
"orcid": "0000-0002-8476-6032",
"clpid": "Jette-Carina-I"
},
{
"family_name": "Bachman",
"given_name": "Shoshana",
"clpid": "Bachman-Shoshana"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first nickel-catalyzed enantioselective allylic alkylation of lactone and lactam substrates to deliver products bearing an all-carbon quaternary stereocenter is reported. The reaction, which utilizes a commercially available chiral bisphosphine ligand, proceeds in good yield with a high level of enantioselectivity (up to 90% ee) on a range of unactivated allylic alcohols for both lactone and lactam nucleophiles. The utility of this method is further highlighted via a number of synthetically useful product transformations.",
"doi": "10.1039/c7sc05216b",
"pmcid": "PMC5912103",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2018-03-07",
"series_number": "9",
"volume": "2018",
"issue": "9",
"pages": "2547-2551"
},
{
"id": "authors:yyr8j-bgq68",
"collection": "authors",
"collection_id": "yyr8j-bgq68",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180712-081511897",
"type": "conference_item",
"title": "Total synthesis of (\u00b1)-phomoidride D: A 22 year odyssey",
"author": [
{
"family_name": "Leung",
"given_name": "Joyce",
"clpid": "Leung-Joyce"
},
{
"family_name": "Bederman",
"given_name": "Aaron",
"clpid": "Bederman-A"
},
{
"family_name": "Njardarson",
"given_name": "Jon",
"clpid": "Njardarson-J"
},
{
"family_name": "Spiegel",
"given_name": "David",
"clpid": "Spiegel-D-S"
},
{
"family_name": "Murphy",
"given_name": "Graham",
"clpid": "Murphy-G"
},
{
"family_name": "Hama",
"given_name": "Naota",
"clpid": "Hama-Naota"
},
{
"family_name": "Shirahata",
"given_name": "Tatsuya",
"clpid": "Shirahata-Tatsuya"
},
{
"family_name": "Twenter",
"given_name": "Barry",
"clpid": "Twenter-B"
},
{
"family_name": "Dong",
"given_name": "Ping",
"clpid": "Dong-Ping"
},
{
"family_name": "McDonald",
"given_name": "Ivar",
"orcid": "0000-0003-0356-0655",
"clpid": "McDonald-I"
},
{
"family_name": "Inoue",
"given_name": "Munenori",
"clpid": "Inoue-Munenori"
},
{
"family_name": "Taniguchi",
"given_name": "Nobuaki",
"clpid": "Taniguchi-Nobuaki"
},
{
"family_name": "McMahon",
"given_name": "Travis",
"clpid": "McMahon-T"
},
{
"family_name": "Tao",
"given_name": "Nancy",
"clpid": "Tao-Nancy"
},
{
"family_name": "Schneider",
"given_name": "Chris",
"clpid": "Schneider-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Wood",
"given_name": "John",
"clpid": "Wood-J-L"
}
],
"abstract": "Recent efforts in our labs. have culminated in a completed synthesis of the phomoidride D via a strategy that evolved over a 22-yr period. The evolution of this strategies will be discussed.",
"publisher": "Caltech Library",
"publication_date": "2018-03"
},
{
"id": "authors:03pzg-hmp58",
"collection": "authors",
"collection_id": "03pzg-hmp58",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180413-085522795",
"type": "conference_item",
"title": "Award Address (ACS Award for Creative Work in Synthetic Organic Chemistry sponsored by MilliporeSigma). Complex natural products as a driving force for discovery in organic chemistry",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Our lab. is deeply interested in the discovery and development of new reaction methodol. en route to the chem. synthesis of\ncomplex bioactive mols. Over the course of the past seventeen years, research in our group at the California Institute of\nTechnol. has been initiated in the general area of synthetic chem., with a focus on the development of new strategies for the prepn. of complex mols., including natural products that possess interesting structural, biol., and phys. properties. Concurrent to this program of target driven synthesis is a strong effort directed toward the development of new techniques and reaction methods, which are useful for a range of applications. Typically, the complex target structure is used as an inspiration for the discovery of new reactions and technologies that may eventually be regarded as general synthetic methodol. Consequently, this approach provides access to (a) novel, medicinally relevant structures, (b) a general method for their synthesis, and (c) new synthetic methods that will be beneficial for a host of applications. Thus, In the process of completing the synthesis of a range of important compds., we have developed a no. of new methods that enabled their access. These topics will be\ndiscussed in the lecture.",
"publisher": "Caltech Library",
"publication_date": "2018-03"
},
{
"id": "authors:5w22z-3mm70",
"collection": "authors",
"collection_id": "5w22z-3mm70",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200415-101219737",
"type": "article",
"title": "Total Synthesis of (\u00b1)-Phomoidride\u2005D",
"author": [
{
"family_name": "Leung",
"given_name": "Joyce C.",
"clpid": "Leung-Joyce-C"
},
{
"family_name": "Bedermann",
"given_name": "Aaron A.",
"clpid": "Bedermann-A-A"
},
{
"family_name": "Njardarson",
"given_name": "J\u00f3n T.",
"clpid": "Njardarson-J-T"
},
{
"family_name": "Spiegel",
"given_name": "David A.",
"clpid": "Spiegel-D-A"
},
{
"family_name": "Murphy",
"given_name": "Graham K.",
"clpid": "Murphy-G-K"
},
{
"family_name": "Hama",
"given_name": "Naoto",
"clpid": "Hama-N"
},
{
"family_name": "Twenter",
"given_name": "Barry M.",
"clpid": "Twenter-B-M"
},
{
"family_name": "Dong",
"given_name": "Ping",
"clpid": "Dong-Ping"
},
{
"family_name": "Shirahata",
"given_name": "Tatsuya",
"clpid": "Shirahata-Tatsuya"
},
{
"family_name": "McDonald",
"given_name": "Ivar M.",
"clpid": "McDonald-I-M"
},
{
"family_name": "Inoue",
"given_name": "Munenori",
"clpid": "Inoue-Munenori"
},
{
"family_name": "Taniguchi",
"given_name": "Nobuaki",
"clpid": "Taniguchi-Nobuaki"
},
{
"family_name": "McMahon",
"given_name": "Travis C.",
"clpid": "McMahon-T-C"
},
{
"family_name": "Schneider",
"given_name": "Christopher M.",
"clpid": "Schneider-C-M"
},
{
"family_name": "Tao",
"given_name": "Nancy",
"clpid": "Tao-Nancy"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Wood",
"given_name": "John L.",
"orcid": "0000-0002-9066-5588",
"clpid": "Wood-J-L"
}
],
"abstract": "Described herein is a synthetic strategy for the total synthesis of (\u00b1)\u2010phomoidride\u2005D. This highly efficient and stereoselective approach provides rapid assembly of the carbocyclic core by way of a tandem phenolic oxidation/intramolecular Diels\u2013Alder cycloaddition. A subsequent SmI2\u2010mediated cyclization cascade delivers an isotwistane intermediate poised for a Wharton fragmentation that unveils the requisite bicyclo[4.3.1]decene skeleton and sets the stage for synthesis completion.",
"doi": "10.1002/anie.201712369",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2018-02-12",
"series_number": "7",
"volume": "57",
"issue": "7",
"pages": "1991-1994"
},
{
"id": "authors:dtyqq-09619",
"collection": "authors",
"collection_id": "dtyqq-09619",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170906-153516673",
"type": "article",
"title": "Progress towards the total synthesis of hamigerans C and D: a direct approach to an elaborated 6-7-5 carbocyclic core",
"author": [
{
"family_name": "Duquette",
"given_name": "Douglas Charles",
"clpid": "Duquette-Douglas-C"
},
{
"family_name": "Jensen",
"given_name": "Thomas",
"clpid": "Jensen-Thomas"
},
{
"family_name": "Stoltz",
"given_name": "Brian Mark",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The hamigeran family of natural products has been the target of numerous synthetic efforts because of its biological activity and interesting structural properties. Herein, we disclose our efforts toward the synthesis of hamigerans C and D, unique among the initially isolated members because of their 6-7-5 carbocyclic core. Our approach directly targets this tricyclic motif by sequential Negishi and Heck coupling reactions, yielding an advanced intermediate with all necessary carbons and sufficient functionality poised for completion of the synthesis of these two natural products.",
"doi": "10.1038/ja.2017.96",
"pmcid": "PMC5788718",
"issn": "0021-8820",
"publisher": "Nature Publishing Group",
"publication": "Journal of Antibiotics",
"publication_date": "2018-02",
"series_number": "2",
"volume": "71",
"issue": "2",
"pages": "263-267"
},
{
"id": "authors:qfy4g-mnx45",
"collection": "authors",
"collection_id": "qfy4g-mnx45",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171129-075958117",
"type": "article",
"title": "Isocanthine Synthesis via Rh(III)-Catalyzed Intramolecular C-H Functionalization",
"author": [
{
"family_name": "Chen",
"given_name": "Anthony Y.",
"clpid": "Chen-Anthony-Y"
},
{
"family_name": "Lu",
"given_name": "Qianqian",
"clpid": "Lu-Qianqian"
},
{
"family_name": "Fu",
"given_name": "Yao",
"orcid": "0000-0003-2282-4839",
"clpid": "Fu-Yao"
},
{
"family_name": "Sarpong",
"given_name": "Richmond",
"orcid": "0000-0002-0028-6323",
"clpid": "Sarpong-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
}
],
"abstract": "An efficient synthesis of substituted isocanthines has been achieved using an intramolecular Rh(III)-catalyzed C\u2013H functionalization of alkyne-tethered indoles in the presence of catalytic tris(acetonitrile)pentamethylcyclopentadienylrhodium(III) hexafluoroantimonate and stoichiometric copper(II) acetate. This isocanthine synthesis tolerates a variety of electronically diverse 5- or 6-substituted indoles with N-tethered alkyne coupling partners and can also be extended to pyrrole derivatives for the synthesis of annulated 5-azaindoles.",
"doi": "10.1021/acs.joc.7b02731",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2018-01-05",
"series_number": "1",
"volume": "83",
"issue": "1",
"pages": "330-337"
},
{
"id": "authors:5nd0b-rfp58",
"collection": "authors",
"collection_id": "5nd0b-rfp58",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171219-073339592",
"type": "article",
"title": "Atmospheric autoxidation is increasingly important in urban and suburban North America",
"author": [
{
"family_name": "Praske",
"given_name": "Eric",
"orcid": "0000-0001-7169-4423",
"clpid": "Praske-Eric"
},
{
"family_name": "Otkj\u00e6r",
"given_name": "Rasmus V.",
"orcid": "0000-0002-6094-1828",
"clpid": "Otkj\u00e6r-Rasmus-V"
},
{
"family_name": "Crounse",
"given_name": "John D.",
"orcid": "0000-0001-5443-729X",
"clpid": "Crounse-John-D"
},
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Kjaergaard",
"given_name": "Henrik G.",
"orcid": "0000-0002-7275-8297",
"clpid": "Kjaergaard-Henrik-G"
},
{
"family_name": "Wennberg",
"given_name": "Paul O.",
"orcid": "0000-0002-6126-3854",
"clpid": "Wennberg-P-O"
}
],
"abstract": "Gas-phase autoxidation\u2014regenerative peroxy radical formation following intramolecular hydrogen shifts\u2014is known to be important in the combustion of organic materials. The relevance of this chemistry in the oxidation of organics in the atmosphere has received less attention due, in part, to the lack of kinetic data at relevant temperatures. Here, we combine computational and experimental approaches to investigate the rate of autoxidation for organic peroxy radicals (RO_2) produced in the oxidation of a prototypical atmospheric pollutant, n-hexane. We find that the reaction rate depends critically on the molecular configuration of the RO_2 radical undergoing hydrogen transfer (H-shift). RO_2 H-shift rate coefficients via transition states involving six- and seven-membered rings (1,5 and 1,6 H-shifts, respectively) of \u03b1-OH hydrogens (HOC-H) formed in this system are of order 0.1 s^(\u22121) at 296 K, while the 1,4 H-shift is calculated to be orders of magnitude slower. Consistent with H-shift reactions over a substantial energetic barrier, we find that the rate coefficients of these reactions increase rapidly with temperature and exhibit a large, primary, kinetic isotope effect. The observed H-shift rate coefficients are sufficiently fast that, as a result of ongoing NO_x emission reductions, autoxidation is now competing with bimolecular chemistry even in the most polluted North American cities, particularly during summer afternoons when NO levels are low and temperatures are elevated.",
"doi": "10.1073/pnas.1715540115",
"pmcid": "PMC5776813",
"issn": "0027-8424",
"publisher": "National Academy of Sciences",
"publication": "Proceedings of the National Academy of Sciences of the United States of America",
"publication_date": "2018-01-02",
"series_number": "1",
"volume": "115",
"issue": "1",
"pages": "64-69"
},
{
"id": "authors:2a0bs-rmr72",
"collection": "authors",
"collection_id": "2a0bs-rmr72",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171107-103337734",
"type": "article",
"title": "Model Studies to Access the [6,7,5,5]-Core of Ineleganolide Using Tandem Translactonization-Cope or Cyclopropanation-Cope Rearrangements as Key Steps",
"author": [
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-Jennifer-L"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-Amanda-C"
},
{
"family_name": "Smith",
"given_name": "Russell C.",
"clpid": "Smith-Russell-C"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Recently, we reported a convergent cyclopropanation\u2013Cope approach to the core of ineleganolide, which was the first disclosed synthesis of the core of the norditerpene natural product ineleganolide. In this complementary work, a model system for the core of ineleganolide has been prepared through a series of tandem cyclopropanation\u2013Cope and translactonization\u2013Cope rearrangements. Work with this model system has enriched our understanding of the cyclopropanation\u2013Cope rearrangement sequence. Additionally, research into this model system has driven the development of tandem translactonization\u2013Cope rearrangements.",
"doi": "10.1021/acs.joc.7b02030",
"pmcid": "PMC5732049",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2017-12-15",
"series_number": "24",
"volume": "82",
"issue": "24",
"pages": "13051-13067"
},
{
"id": "authors:0v80w-hax34",
"collection": "authors",
"collection_id": "0v80w-hax34",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171004-144313124",
"type": "article",
"title": "Catalytic Reduction of Alkyl and Aryl Bromides Using Propan-2-ol",
"author": [
{
"family_name": "Haibach",
"given_name": "Michael C.",
"orcid": "0000-0001-8383-5633",
"clpid": "Haibach-M-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "Milstein's complex, (PNN)RuHCl(CO), catalyzes the efficient reduction of aryl and alkyl halides under relatively mild conditions by using propan-2-ol and a base. Sterically hindered tertiary and neopentyl substrates are reduced efficiently, as well as more functionalized aryl and alkyl bromides. The reduction process is proposed to occur by radical abstraction/hydrodehalogenation steps at ruthenium. Our research represents a safer and more sustainable alternative to typical silane, lithium aluminium hydride, and tin-based conditions for these reductions.",
"doi": "10.1002/anie.201708800",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2017-11-20",
"series_number": "47",
"volume": "56",
"issue": "47",
"pages": "15123-15126"
},
{
"id": "authors:9n5sr-veb37",
"collection": "authors",
"collection_id": "9n5sr-veb37",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170914-131404458",
"type": "article",
"title": "Enantioselective Pd-Catalyzed Decarboxylative Allylic Alkylation of Thiopyranones. Access to Acyclic, Stereogenic \u03b1-Quaternary Ketones",
"author": [
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Bartberger",
"given_name": "Michael D.",
"orcid": "0000-0002-5167-3139",
"clpid": "Bartberger-Michael-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic, enantioselective decarboxylative allylic alkylation of 4-thiopyranones is reported. The \u03b1-quaternary 4-thiopyranones produced are challenging to access by standard enolate alkylation owing to facile ring-opening \u03b2-sulfur elimination. In addition, reduction of the carbon\u2013sulfur bonds provides access to elusive acyclic \u03b1-quaternary ketones. The alkylated products are obtained in up to 92% yield and 94% enantiomeric excess.",
"doi": "10.1021/acs.orglett.7b02354",
"pmcid": "PMC5632216",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2017-10-06",
"series_number": "19",
"volume": "19",
"issue": "19",
"pages": "5007-5009"
},
{
"id": "authors:z0mkj-0j434",
"collection": "authors",
"collection_id": "z0mkj-0j434",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170918-101644915",
"type": "article",
"title": "Sequential Ruthenium Catalysis for Olefin Isomerization and Oxidation: Application to the Synthesis of Unusual Amino Acids",
"author": [
{
"family_name": "Liniger",
"given_name": "Marc",
"orcid": "0000-0002-4273-2942",
"clpid": "Liniger-Marc"
},
{
"family_name": "Liu",
"given_name": "Yiyang",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "How can you use a ruthenium isomerization catalyst twice? A ruthenium-catalyzed sequence for the formal two-carbon scission of allyl groups to carboxylic acids has been developed. The reaction includes an initial isomerization step using commercially available ruthenium catalysts followed by in situ transformation of the complex to a metal-oxo species, which is capable of catalyzing subsequent oxidation reactions. The method enables enantioselective syntheses of challenging \u03b1-tri- and tetrasubstituted \u03b1-amino acids including an expedient total synthesis of the antiepileptic drug levetiracetam.",
"doi": "10.1021/jacs.7b08496",
"pmcid": "PMC5628162",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2017-10-03",
"series_number": "39",
"volume": "139",
"issue": "39",
"pages": "13944-13949"
},
{
"id": "authors:rghz3-ppf81",
"collection": "authors",
"collection_id": "rghz3-ppf81",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170905-134054944",
"type": "article",
"title": "Enantioselective Catalysis Coupled with Stereodivergent Cyclization Strategies Enables Rapid Syntheses of (+)-Limaspermidine and (+)-Kopsihainanine A",
"author": [
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Donckele",
"given_name": "Etienne J.",
"orcid": "0000-0001-9112-1753",
"clpid": "Donckele-Etienne-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Enantioselective Pd-catalyzed allylic alkylations of dihydropyrido[1,2-a]indolone (DHPI) substrates were used to construct the C20-quaternary stereocenters of multiple monoterpene indole alkaloids. Stereodivergent Pictet\u2013Spengler and Bischler\u2013Napieralski cyclization/reduction cascades furnish the cis- and trans-fused azadecalin subunits present in Aspidosperma and Kopsia alkaloids, respectively, en\u2005route to highly efficient syntheses of (+)-limaspermidine and (+)-kopsihainanine\u2005A.",
"doi": "10.1002/anie.201707304",
"pmcid": "PMC5896324",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2017-10-02",
"series_number": "41",
"volume": "56",
"issue": "41",
"pages": "12624-12627"
},
{
"id": "authors:x2gxj-dqg48",
"collection": "authors",
"collection_id": "x2gxj-dqg48",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170719-091950600",
"type": "article",
"title": "Enantioselective Synthesis of Acyclic \u03b1-Quaternary Carboxylic Acid Derivatives through Iridium-Catalyzed Allylic Alkylation",
"author": [
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first highly enantioselective iridium-catalyzed allylic alkylation providing access to products bearing an allylic all-carbon quaternary stereogenic center has been developed. The reaction utilizes a masked acyl cyanide (MAC) reagent, which enables the one-pot preparation of \u03b1-quaternary carboxylic acids, esters, and amides with a high degree of enantioselectivity. The utility of these products is further explored via a series of diverse product transformations.",
"doi": "10.1002/anie.201707015",
"pmcid": "PMC5674796",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2017-09-11",
"series_number": "38",
"volume": "56",
"issue": "38",
"pages": "11545-11548"
},
{
"id": "authors:h8xta-xst18",
"collection": "authors",
"collection_id": "h8xta-xst18",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170707-100417876",
"type": "article",
"title": "Asymmetric Synthesis of All-Carbon Quaternary Spirocycles via a Catalytic Enantioselective Allylic Alkylation Strategy",
"author": [
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Rapid access to enantioenriched spirocycles possessing a 1,4-dicarbonyl moiety spanning an all-carbon quaternary stereogenic spirocenter was achieved using a masked bromomethyl vinyl ketone reagent. The developed protocol entails an enantioselective palladium-catalyzed allylic alkylation reaction followed by a one-pot unmasking/RCM sequence that provides access to the spirocyclic compounds in good yields and selectivities.",
"doi": "10.1016/j.tetlet.2017.07.022",
"pmcid": "PMC5578629",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2017-08-23",
"series_number": "34",
"volume": "58",
"issue": "34",
"pages": "3341-3343"
},
{
"id": "authors:829hk-ctn24",
"collection": "authors",
"collection_id": "829hk-ctn24",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170720-100846797",
"type": "article",
"title": "Enantioselective Total Synthesis of Nigelladine A via Late-Stage C\u2013H Oxidation Enabled by an Engineered P450 Enzyme",
"author": [
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-Steven-A"
},
{
"family_name": "Romney",
"given_name": "David K.",
"orcid": "0000-0003-0498-7597",
"clpid": "Romney-David-K"
},
{
"family_name": "Arnold",
"given_name": "Frances H.",
"orcid": "0000-0002-4027-364X",
"clpid": "Arnold-F-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective total synthesis of the norditerpenoid alkaloid nigelladine A is described. Strategically, the synthesis relies on a late-stage C\u2013H oxidation of an advanced intermediate. While traditional chemical methods failed to deliver the desired outcome, an engineered cytochrome P450 enzyme was employed to effect a chemo- and regioselective allylic C\u2013H oxidation in the presence of four oxidizable positions. The enzyme variant was readily identified from a focused library of three enzymes, allowing for completion of the synthesis without the need for extensive screening.",
"doi": "10.1021/jacs.7b05196",
"pmcid": "PMC5679227",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2017-08-02",
"series_number": "30",
"volume": "139",
"issue": "30",
"pages": "10196-10199"
},
{
"id": "authors:ej7em-za941",
"collection": "authors",
"collection_id": "ej7em-za941",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170913-084235803",
"type": "conference_item",
"title": "Recent developments in stereoselective iridium-catalyzed allylic alkylation methodologies",
"author": [
{
"family_name": "Shockley",
"given_name": "Samantha",
"clpid": "Shockley-S-E"
},
{
"family_name": "Hethcox",
"given_name": "Caleb",
"clpid": "Hethcox-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report our ongoing studies in the field of iridium-catalyzed allylic alkylation chem. The first regio-,\ndiastereo-, and enantioselective transition-metal-catalyzed allylic alkylation reaction forming vicinal tertiary\nand all-carbon quaternary stereocenters between prochiral enolates and an aliph.-substituted electrophile is\ndisclosed. Crit. to the success of this new reaction is the identity and ubiquity of the chloride counterion in\naddn. to the use of proton sponge, the combination of which affords excellent regio- and enantioselectivities along with good yields and diastereoselectivities. Addnl., a no. of transformations were carried out on the alkylation products to demonstrate the value of this method in rapidly accessing highly functionalized, stereochem. rich polycyclic scaffolds. Further exploration of this chem. has continued to expand the scope of these types of transformations with respect to the nucleophile and electrophile. Our recent efforts in this field will be discussed.",
"publisher": "Caltech Library",
"publication_date": "2017-08"
},
{
"id": "authors:xjath-wzj74",
"collection": "authors",
"collection_id": "xjath-wzj74",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170919-130910278",
"type": "conference_item",
"title": "Twists and turns of lactam research",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The importance of the amide bond cannot be overstated. Typical amides are planar structures, however, amide\nbonds can be highly twisted such as in bicyclic bridgehead lactams. The distortion of the orbitals from planarity\nand the pyramidalization of the nitrogen from sp toward sp dramatically affect the stability and reactivity of\nanti-Bredt amides. In 2006, our group published the first unambiguous synthesis and characterization of 2-\nquinuclidonium tetrafluoroborate. Since then we have been fascinated with the synthesis and characterization\nof such strained reactive lactams. We have also pursued the synthesis of a series of novel stereogenic lactams\nthat can be employed as intermediates in multi-step synthesis. The lecture will discuss our efforts in these\nvibrant research areas. Looking ahead, the limits are still open for the synthesis of more or less reactive but\nstructurally unique and often twisted amides.",
"publisher": "Caltech Library",
"publication_date": "2017-08"
},
{
"id": "authors:aw35y-ac118",
"collection": "authors",
"collection_id": "aw35y-ac118",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170623-095559709",
"type": "article",
"title": "Enantioselective Construction of Acyclic Quaternary Carbon Stereocenters: Palladium-Catalyzed Decarboxylative Allylic Alkylation of Fully-Substituted Amide Enolates",
"author": [
{
"family_name": "Starkov",
"given_name": "Pavel",
"orcid": "0000-0003-1421-4731",
"clpid": "Starkov-Pavel"
},
{
"family_name": "Moore",
"given_name": "Jared T.",
"clpid": "Moore-Jared-T"
},
{
"family_name": "Duquette",
"given_name": "Douglas C.",
"clpid": "Duquette-Douglas-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Marek",
"given_name": "Ilan",
"orcid": "0000-0001-9154-2320",
"clpid": "Marek-Ilan"
}
],
"abstract": "We report a divergent and modular protocol for the preparation of acyclic molecular frameworks containing newly created quaternary carbon stereocenters. Central to this approach is a sequence composed of a (1) regioselective and -retentive preparation of allyloxycarbonyl-trapped fully substituted stereodefined amide enolates and of a (2) enantioselective palladium-catalyzed decarboxylative allylic alkylation reaction using a novel bisphosphine ligand.",
"doi": "10.1021/jacs.7b04086",
"pmcid": "PMC5555155",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2017-07-19",
"series_number": "28",
"volume": "139",
"issue": "28",
"pages": "9615-9620"
},
{
"id": "authors:tpb7e-mcf81",
"collection": "authors",
"collection_id": "tpb7e-mcf81",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170519-105858158",
"type": "article",
"title": "Polycyclic Furanobutenolide-Derived Cembranoid and Norcembranoid Natural Products: Biosynthetic Connections and Synthetic Efforts",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The polycyclic furanobutenolide-derived cembranoid and norcembranoid natural products are a family of congested, stereochemically complex, and extensively oxygenated polycyclic diterpenes and norditerpenes. Although the elegant architectures and biological activity profiles of these natural products have captured the attention of chemists since the isolation of the first members of the family in the 1990s, the de novo synthesis of only a single polycyclic furanobutenolide-derived cembranoid and norcembranoid has been accomplished. This article begins with a brief discussion of the proposed biosyntheses and biosynthetic connections among the polycyclic furanobutenolide-derived cembranoids and norcembranoids and then provides a comprehensive review of the synthetic efforts toward each member of the natural product family, including biomimetic, semisynthetic, and de novo synthetic strategies. This body of knowledge has been gathered to provide insight into the reactivity and constraints of these compact and highly oxygenated polycyclic structures, as well as to offer guidance for future synthetic endeavors.",
"doi": "10.1021/acs.chemrev.7b00083",
"pmcid": "PMC5497599",
"issn": "0009-2665",
"publisher": "American Chemical Society",
"publication": "Chemical Reviews",
"publication_date": "2017-06-28",
"series_number": "12",
"volume": "117",
"issue": "12",
"pages": "7878-7909"
},
{
"id": "authors:g8sbn-ghs16",
"collection": "authors",
"collection_id": "g8sbn-ghs16",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170502-104649589",
"type": "article",
"title": "Ionic and Neutral Mechanisms for C\u2013H Bond Silylation of Aromatic Heterocycles Catalyzed by Potassium t-Butoxide",
"author": [
{
"family_name": "Banerjee",
"given_name": "Shibdas",
"orcid": "0000-0002-3424-8157",
"clpid": "Banerjee-Shibdas"
},
{
"family_name": "Yang",
"given_name": "Yun-Fang",
"orcid": "0000-0002-6287-1640",
"clpid": "Yang-Yun-Fang"
},
{
"family_name": "Jenkins",
"given_name": "Ian D.",
"orcid": "0000-0003-3961-2277",
"clpid": "Jenkins-I-D"
},
{
"family_name": "Liang",
"given_name": "Yong",
"orcid": "0000-0002-7225-7062",
"clpid": "Liang-Yong"
},
{
"family_name": "Toutov",
"given_name": "Anton Alexandrovich",
"orcid": "0000-0002-6561-0462",
"clpid": "Toutov-A-A"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Schuman",
"given_name": "David P.",
"clpid": "Schuman-D-P"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Krenske",
"given_name": "Elizabeth H.",
"orcid": "0000-0003-1911-0501",
"clpid": "Krenske-E-H"
},
{
"family_name": "Houk",
"given_name": "Kendall N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-K-N"
},
{
"family_name": "Zare",
"given_name": "Richard N.",
"orcid": "0000-0001-5266-4253",
"clpid": "Zare-R-N"
}
],
"abstract": "Exploiting C\u2013H bond activation is difficult, although some success has been achieved using precious metal catalysts. Recently, it was reported that C\u2013H bonds in aromatic heterocycles were converted to C\u2013Si bonds by reaction with hydrosilanes under the catalytic action of potassium t-butoxide alone. The use of Earth-abundant potassium cation as a catalyst for C\u2013H bond functionalization seems to be without precedent, and no mechanism for the process was established. Using ambient ionization mass spectrometry, we are able to identify crucial ionic intermediates present during the C\u2013H silylation reaction. We propose a plausible catalytic cycle, which involves a pentacoordinate silicon intermediate consisting of silane reagent, substrate, and the t-butoxide catalyst. Heterolysis of the Si\u2013H bond, deprotonation of the heteroarene, addition of the heteroarene carbanion to the silylether, and dissociation of t-butoxide from silicon lead to the silylated heteroarene product. The steps of the silylation mechanism may follow either an ionic route involving K^+ and tBuO^\u2013 ions or a neutral heterolytic route involving the [KOtBu]_4 tetramer. Both mechanisms are consistent with the ionic intermediates detected experimentally. We also present reasons why potassium t-butoxide is an active catalyst whereas sodium t-butoxide and lithium t-butoxide are not, and we explain the relative reactivities of different (hetero)arenes in the silylation reaction. The unique role of potassium t-butoxide is traced, in part, to the stabilization of crucial intermediates through cation-\u03c0 interactions.",
"doi": "10.1021/jacs.6b13032",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2017-05-24",
"series_number": "20",
"volume": "139",
"issue": "20",
"pages": "6880-6887"
},
{
"id": "authors:e40wa-gyv79",
"collection": "authors",
"collection_id": "e40wa-gyv79",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170413-121146154",
"type": "article",
"title": "Potassium tert-Butoxide-Catalyzed Dehydrogenative C\u2013H Silylation of Heteroaromatics: A Combined Experimental and Computational Mechanistic Study",
"author": [
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Schuman",
"given_name": "David P.",
"clpid": "Schuman-D-P"
},
{
"family_name": "Yang",
"given_name": "Yun-Fang",
"orcid": "0000-0002-6287-1640",
"clpid": "Yang-Yun-Fang"
},
{
"family_name": "Toutov",
"given_name": "Anton A.",
"orcid": "0000-0002-6561-0462",
"clpid": "Toutov-A-A"
},
{
"family_name": "Liang",
"given_name": "Yong",
"orcid": "0000-0002-7225-7062",
"clpid": "Liang-Yong"
},
{
"family_name": "Klare",
"given_name": "Hendrik F. T.",
"orcid": "0000-0003-3748-6609",
"clpid": "Klare-H-F-T"
},
{
"family_name": "Nesnas",
"given_name": "Nasri",
"orcid": "0000-0003-3511-940X",
"clpid": "Nesnas-N"
},
{
"family_name": "Oestreich",
"given_name": "Martin",
"orcid": "0000-0002-1487-9218",
"clpid": "Oestreich-M"
},
{
"family_name": "Blackmond",
"given_name": "Donna G.",
"orcid": "0000-0001-9829-8375",
"clpid": "Blackmond-D-G"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Banerjee",
"given_name": "Shibdas",
"orcid": "0000-0002-3424-8157",
"clpid": "Banerjee-Shibdas"
},
{
"family_name": "Zare",
"given_name": "Richard N.",
"orcid": "0000-0001-5266-4253",
"clpid": "Zare-R-N"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-K-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We recently reported a new method for the direct dehydrogenative C\u2013H silylation of heteroaromatics utilizing Earth-abundant potassium tert-butoxide. Herein we report a systematic experimental and computational mechanistic investigation of this transformation. Our experimental results are consistent with a radical chain mechanism. A trialkylsilyl radical may be initially generated by homolytic cleavage of a weakened Si\u2013H bond of a hypercoordinated silicon species as detected by IR, or by traces of oxygen which can generate a reactive peroxide by reaction with (KOt-Bu)_4 as indicated by density functional theory (DFT) calculations. Radical clock and kinetic isotope experiments support a mechanism in which the C\u2013Si bond is formed through silyl radical addition to the heterocycle followed by subsequent \u03b2-hydrogen scission. DFT calculations reveal a reasonable energy profile for a radical mechanism and support the experimentally observed regioselectivity. The silylation reaction is shown to be reversible, with an equilibrium favoring products due to the generation of H_2 gas. In situ NMR experiments with deuterated substrates show that H_2 is formed by a cross-dehydrogenative mechanism. The stereochemical course at the silicon center was investigated utilizing a ^2H-labeled silolane probe; complete scrambling at the silicon center was observed, consistent with a number of possible radical intermediates or hypercoordinate silicates.",
"doi": "10.1021/jacs.6b13031",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2017-05-24",
"series_number": "20",
"volume": "139",
"issue": "20",
"pages": "6867-6879"
},
{
"id": "authors:g5rmc-env78",
"collection": "authors",
"collection_id": "g5rmc-env78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170316-160746005",
"type": "article",
"title": "Enantioselective Iridium-Catalyzed Allylic Alkylation Reactions of Masked Acyl Cyanide Equivalents",
"author": [
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective iridium-catalyzed allylic alkylation reaction of a masked acyl cyanide (MAC) reagent has been developed. The transformation allows for the use of an umpoled synthon, which serves as a carbon monoxide equivalent. The reaction proceeds with good yield and excellent selectivity up to gram scale for a wide range of substituted allylic electrophiles, delivering products amenable to the synthesis of highly desirable, enantioenriched vinylated \u03b1-aryl carbonyl derivatives.",
"doi": "10.1021/acs.orglett.7b00449",
"pmcid": "PMC5470644",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2017-04-07",
"series_number": "7",
"volume": "19",
"issue": "7",
"pages": "1527-1529"
},
{
"id": "authors:yzan4-78e47",
"collection": "authors",
"collection_id": "yzan4-78e47",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170503-152924409",
"type": "conference_item",
"title": "Complex natural products as a driving force for discovery in organic chemistry",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Our lab. is deeply interested in the discovery and development of new reaction methodol. en route to the chem. synthesis of complex bioactive mols. Over the course of the past ten years, research in our group at the California Institute of Technol. has been initiated in the general area of synthetic chem., with a focus on the development of new strategies for the prepn. of complex mols., including natural products that possess interesting structural, biol., and phys. properties. Concurrent to this program of target driven synthesis is a strong effort directed toward the development of new techniques and reaction methods, which will be useful for a range of applications. Typically, the complex target structure is used as an inspiration for the discovery of new reactions and technologies that may eventually be regarded as general synthetic methodol. Consequently, this approach provides access to a) novel, medicinally relevant structures, b) a general method for their synthesis, and c) new synthetic methods that will be beneficial for a host of applications. Our group has been heavily involved in the synthesis of complex natural products such as the cyanthiwigins, quinocarcin, lemonomycin, and the dragmacidins. These naturally occurring mols. possess promising biol. properties ranging from activity against antibiotic-resistant bacteria, to antiproliferative, to anti-HIV action. Furthermore, they are structurally novel and are inherently a challenge to the state-of-the-art in synthetic\nchem. In the process of completing the synthesis of these important compds., we have developed a no. of new methods that enabled their access. These topics will be discussed in the lecture.",
"publisher": "Caltech Library",
"publication_date": "2017-04"
},
{
"id": "authors:kmazs-dvq68",
"collection": "authors",
"collection_id": "kmazs-dvq68",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170211-113501417",
"type": "article",
"title": "Advances in Stereoconvergent Catalysis from 2005 to 2015: Transition-Metal-Mediated Stereoablative Reactions, Dynamic Kinetic Resolutions, and Dynamic Kinetic Asymmetric Transformations",
"author": [
{
"family_name": "Bhat",
"given_name": "Vikram",
"orcid": "0000-0001-5621-5121",
"clpid": "Bhat-Vikram"
},
{
"family_name": "Welin",
"given_name": "Eric R.",
"orcid": "0000-0002-1760-4121",
"clpid": "Welin-Eric-R"
},
{
"family_name": "Guo",
"given_name": "Xuelei",
"clpid": "Guo-Xuelei"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Stereoconvergent catalysis is an important subset of asymmetric synthesis that encompasses stereoablative transformations, dynamic kinetic resolutions, and dynamic kinetic asymmetric transformations. Initially, only enzymes were known to catalyze dynamic kinetic processes, but recently various synthetic catalysts have been developed. This Review summarizes major advances in nonenzymatic, transition-metal-promoted dynamic asymmetric transformations reported between 2005 and 2015.",
"doi": "10.1021/acs.chemrev.6b00731",
"pmcid": "PMC5516946",
"issn": "0009-2665",
"publisher": "American Chemical Society",
"publication": "Chemical Reviews",
"publication_date": "2017-03-08",
"series_number": "5",
"volume": "117",
"issue": "5",
"pages": "4528-4561"
},
{
"id": "authors:c9y0p-ab817",
"collection": "authors",
"collection_id": "c9y0p-ab817",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-101807646",
"type": "article",
"title": "Oxidative Fragmentations and Skeletal Rearrangements of Oxindole Derivatives",
"author": [
{
"family_name": "Klare",
"given_name": "Hendrik F. T.",
"orcid": "0000-0003-3748-6609",
"clpid": "Klare-H-F-T"
},
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "Duquette",
"given_name": "Douglas C.",
"clpid": "Duquette-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An oxidative sequence for the conversion of oxindoles to structurally distinct heterocyclic scaffolds and aniline derivatives is disclosed by the combination of a copper-catalyzed C\u2013H peroxidation and subsequent base-mediated fragmentation reaction. In contrast to classic enzymatic (i.e., kynurenine pathway) and biomimetic methods (i.e., Witkop\u2013Winterfeldt oxidation) for oxidative indole cleavage, this protocol allows for the incorporation of external nucleophiles. The new transformation displays broad functional group tolerance and is applicable to tryptophan derivatives, opening potential new avenues for postsynthetic modification of polypeptides, bioconjugation, and unnatural amino acid synthesis.",
"doi": "10.1021/acs.orglett.6b03789",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2017-03-03",
"series_number": "5",
"volume": "19",
"issue": "5",
"pages": "988-991"
},
{
"id": "authors:zh2jx-shw67",
"collection": "authors",
"collection_id": "zh2jx-shw67",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170706-132827697",
"type": "article",
"title": "A Fischer Indolization Strategy toward the Total Synthesis of (\u2013)-Goniomitine",
"author": [
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Kikuchi",
"given_name": "Jun",
"clpid": "Kikuchi-Jun"
},
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A Fischer indolization strategy toward the core of (\u2013)-goniomitine is reported. Initial investigations into the Pd-catalyzed asymmetric allylic alkylation of dihydropyrido[1,2-a]indolone (DHPI) substrates are also discussed.",
"doi": "10.3987/COM-16-S(S)80",
"pmcid": "PMC5502790",
"issn": "0385-5414",
"publisher": "Japan Institute of Heterocyclic Chemistry",
"publication": "Heterocycles",
"publication_date": "2017-02-15",
"series_number": "2",
"volume": "95",
"issue": "2",
"pages": "1245-1253"
},
{
"id": "authors:n1x82-2e617",
"collection": "authors",
"collection_id": "n1x82-2e617",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170104-153320118",
"type": "article",
"title": "Alkali metal hydroxide\u2013catalyzed C(sp)\u2013H bond silylation",
"author": [
{
"family_name": "Toutov",
"given_name": "Anton A.",
"orcid": "0000-0002-6561-0462",
"clpid": "Toutov-A-A"
},
{
"family_name": "Betz",
"given_name": "Kerry N.",
"orcid": "0000-0001-9118-5909",
"clpid": "Betz-K-N"
},
{
"family_name": "Schuman",
"given_name": "David P.",
"clpid": "Schuman-D-P"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Fedorov",
"given_name": "Alexey",
"orcid": "0000-0001-9814-6726",
"clpid": "Fedorov-Alexey"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "Disclosed is a mild, scalable, and chemoselective catalytic cross-dehydrogenative C\u2013H bond functionalization protocol for the construction of C(sp)\u2013Si bonds in a single step. The scope of the alkyne and hydrosilane partners is substantial, providing an entry point into various organosilane building blocks and additionally enabling the discovery of a number of novel synthetic strategies. Remarkably, the optimal catalysts are NaOH and KOH.",
"doi": "10.1021/jacs.6b12114",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2017-02-01",
"series_number": "4",
"volume": "139",
"issue": "4",
"pages": "1668-1674"
},
{
"id": "authors:67s3z-2px14",
"collection": "authors",
"collection_id": "67s3z-2px14",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160908-102036330",
"type": "article",
"title": "Enantioselective, convergent synthesis of the ineleganolide core by a tandem annulation cascade",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-Jennifer-L"
},
{
"family_name": "Smith",
"given_name": "Russell C.",
"clpid": "Smith-Russell-C"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-Amanda-C"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective and diastereoselective approach toward the synthesis of the polycyclic norditerpenoid ineleganolide is disclosed. A palladium-catalyzed enantioselective allylic alkylation is employed to stereoselectively construct the requisite chiral tertiary ether and facilitate the synthesis of a 1,3-cis-cyclopentenediol building block. Careful substrate design enabled the convergent assembly of the ineleganolide [6,7,5,5]-tetracyclic scaffold by a diastereoselective cyclopropanation\u2013Cope rearrangement cascade under unusually mild conditions. Computational evaluation of ground state energies of late-stage synthetic intermediates was used to guide synthetic development and aid in the investigation of the conformational rigidity of these highly constrained and compact polycyclic structures. This work represents the first successful synthesis of the core structure of any member of the furanobutenolide-derived polycyclic norcembranoid diterpene family of natural products. Advanced synthetic manipulations generated a series of natural product-like compounds that were shown to possess selective secretory antagonism of either interleukin-5 or interleukin-17. This bioactivity stands in contrast to the known antileukemic activity of ineleganolide and suggests the norcembranoid natural product core may serve as a useful scaffold for the development of diverse therapeutics.",
"doi": "10.1039/c6sc03347d",
"pmcid": "PMC5321630",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2017-01-01",
"series_number": "1",
"volume": "8",
"issue": "1",
"pages": "507-514"
},
{
"id": "authors:cbs2c-fnw02",
"collection": "authors",
"collection_id": "cbs2c-fnw02",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161205-102308894",
"type": "article",
"title": "Iridium-Catalyzed Stereoselective Allylic Alkylation Reactions with Crotyl Chloride",
"author": [
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development of the first enantio-, diastereo-, and regioselective iridium-catalyzed allylic alkylation reaction of prochiral enolates to form an all-carbon quaternary stereogenic center with an aliphatic-substituted allylic electrophile is disclosed. The reaction proceeds with good to excellent selectivity with a range of substituted tetralone-derived nucleophiles furnishing products bearing a newly formed vicinal tertiary and all-carbon quaternary stereodyad. The utility of this protocol is further demonstrated via a number of synthetically diverse product transformations.",
"doi": "10.1002/anie.201609960",
"pmcid": "PMC5207348",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2016-12-23",
"series_number": "52",
"volume": "55",
"issue": "52",
"pages": "16092-16095"
},
{
"id": "authors:fs1pp-f7g34",
"collection": "authors",
"collection_id": "fs1pp-f7g34",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170103-154034263",
"type": "article",
"title": "Single-step synthesis of 3-hydroxycarbazoles by annulation of electron-rich anilines and quinones",
"author": [
{
"family_name": "Pushkarskaya",
"given_name": "Eugenia",
"clpid": "Pushkarskaya-E"
},
{
"family_name": "Wong",
"given_name": "Brian",
"clpid": "Wong-Brian"
},
{
"family_name": "Han",
"given_name": "Chong",
"clpid": "Han-Chong"
},
{
"family_name": "Capomolla",
"given_name": "Simona",
"clpid": "Capomolla-S"
},
{
"family_name": "Gu",
"given_name": "Chunang",
"clpid": "Gu-Chunang"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
}
],
"abstract": "A single-step synthesis of 3-hydroxycarbazoles has been achieved via annulation of electron-rich anilines and quinones in PhMe/AcOH (4:1) at room temperature. This chemistry tolerates various substituted benzoquinones and naphthoquinones, however, is sensitive to both the electronic and steric properties of the anilines. The desired 3-hydroxycarbazole derivatives are generally produced in moderate yield.",
"doi": "10.1016/j.tetlet.2016.11.009",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2016-12-14",
"series_number": "50",
"volume": "57",
"issue": "50",
"pages": "5653-5657"
},
{
"id": "authors:hyr9k-7bd57",
"collection": "authors",
"collection_id": "hyr9k-7bd57",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161024-103416597",
"type": "article",
"title": "Palladium-Catalyzed Aerobic Intramolecular Aminoacetoxylation of Alkenes Enabled by Catalytic Nitrate",
"author": [
{
"family_name": "Li",
"given_name": "Jiaming",
"orcid": "0000-0001-6646-5693",
"clpid": "Li-Jiaming"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A mild aerobic intramolecular aminoacetoxylation method for the synthesis of pyrrolidine and indoline derivatives was achieved using molecular oxygen as the oxidant. A catalytic NO_x species acts as an electron transfer mediator to access a high-valent palladium intermediate as the presumed active oxidant.",
"doi": "10.1021/acs.orglett.6b02722",
"pmcid": "PMC5512709",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2016-11-04",
"series_number": "21",
"volume": "18",
"issue": "21",
"pages": "5449-5451"
},
{
"id": "authors:c4sqx-gb080",
"collection": "authors",
"collection_id": "c4sqx-gb080",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161024-113042085",
"type": "article",
"title": "A Second-Generation Synthesis of the Cyanthiwigin Natural Product Core",
"author": [
{
"family_name": "Kim",
"given_name": "Kelly E.",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An improved synthesis of the cyanthiwigin natural product core enabled by new catalytic technology is reported. The key double catalytic enantioselective alkylation has been reoptimized using a recently developed protocol employing low loadings of palladium catalyst, thereby facilitating large-scale production of the tricyclic cyanthiwigin framework. Additionally, preparation of the penultimate aldehyde intermediate is expedited through the application of anti-Markovnikov Tsuji\u2013Wacker oxidation.",
"doi": "10.1021/acs.orglett.6b02962",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2016-11-04",
"series_number": "21",
"volume": "18",
"issue": "21",
"pages": "5720-5723"
},
{
"id": "authors:16z45-rse90",
"collection": "authors",
"collection_id": "16z45-rse90",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160927-100108036",
"type": "article",
"title": "Enantioselective Pd-Catalyzed Allylic Alkylation Reactions of Dihydropyrido[1,2-a]indolone Substrates: Efficient Syntheses of (\u2212)-Goniomitine, (+)-Aspidospermidine, and (\u2212)-Quebrachamine",
"author": [
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Kikuchi",
"given_name": "Jun",
"orcid": "0000-0001-9892-8832",
"clpid": "Kikuchi-Jun"
},
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The successful application of dihydropyrido[1,2-a]indolone (DHPI) substrates in Pd-catalyzed asymmetric allylic alkylation chemistry facilitates rapid access to multiple alkaloid frameworks in an enantioselective fashion. Strategic bromination at the indole C3 position greatly improved the allylic alkylation chemistry and enabled a highly efficient Negishi cross-coupling downstream. The first catalytic enantioselective total synthesis of (\u2212)-goniomitine, along with divergent formal syntheses of (+)-aspidospermidine and (\u2212)-quebrachamine, are reported herein.",
"doi": "10.1002/anie.201608138",
"pmcid": "PMC5207349",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2016-10-17",
"series_number": "43",
"volume": "55",
"issue": "43",
"pages": "13529-13532"
},
{
"id": "authors:r3hzt-92k28",
"collection": "authors",
"collection_id": "r3hzt-92k28",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161003-161852128",
"type": "article",
"title": "Catalytic Anti-Markovnikov Transformations of Hindered Terminal Alkenes Enabled by Aldehyde-Selective Wacker-Type Oxidation",
"author": [
{
"family_name": "Kim",
"given_name": "Kelly E.",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Li",
"given_name": "Jiaming",
"orcid": "0000-0001-6646-5693",
"clpid": "Li-Jiaming"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A new strategy for the functionalization of sterically hindered terminal olefins is reported. Alkenes bearing quaternary carbons at the allylic or homoallylic position are readily oxidized to the corresponding aldehydes by palladium/copper/nitrite catalysis. A broad range of functional groups including esters, nitriles, silyl ethers, vinylogous esters, ketones, lactones, and \u03b2-ketoesters are tolerated under the reaction conditions. The crude aldehyde products can be transformed further, enabling direct conversion of hindered terminal alkenes to various other synthetically useful functional groups, resulting in formal anti-Markovnikov hydroamination, among other transformations.",
"doi": "10.1021/jacs.6b08788",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2016-10-12",
"series_number": "40",
"volume": "138",
"issue": "40",
"pages": "13179-13182"
},
{
"id": "authors:d9v50-z7707",
"collection": "authors",
"collection_id": "d9v50-z7707",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170106-160004918",
"type": "article",
"title": "Escherichia coli K1 Modulates Peroxisome Proliferator\u2013Activated Receptor \u03b3 and Glucose Transporter 1 at the Blood-Brain Barrier in Neonatal Meningitis",
"author": [
{
"family_name": "Krishnan",
"given_name": "Subramanian",
"orcid": "0000-0001-5780-7452",
"clpid": "Krishnan-Subramanian"
},
{
"family_name": "Chang",
"given_name": "Alexander C.",
"orcid": "0000-0001-7096-7151",
"clpid": "Chang-Alexander-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Prasadarao",
"given_name": "Nemani V.",
"clpid": "Prasadarao-N-V"
}
],
"abstract": "Escherichia coli K1 meningitis continues to be a major threat to neonatal health. Previous studies demonstrated that outer membrane protein A (OmpA) of E. coli K1 interacts with endothelial cell glycoprotein 96 (Ecgp96) in the blood-brain barrier to enter the central nervous system. Here we show that the interaction between OmpA and Ecgp96 downregulates peroxisome proliferator\u2013activated receptor \u03b3 (PPAR-\u03b3) and glucose transporter 1 (GLUT-1) levels in human brain microvascular endothelial cells, causing disruption of barrier integrity and inhibition of glucose uptake. The suppression of PPAR-\u03b3 and GLUT-1 by the bacteria in the brain microvessels of newborn mice causes extensive pathophysiology owing to interleukin 6 production. Pretreatment with partial or selective PPAR-\u03b3 agonists ameliorate the pathological outcomes of infection by suppressing interleukin 6 production in the brain. Thus, inhibition of PPAR-\u03b3 and GLUT-1 by E. coli K1 is a novel pathogenic mechanism in meningitis, and pharmacological upregulation of PPAR-\u03b3 and GLUT-1 levels may provide novel therapeutic avenues.",
"doi": "10.1093/infdis/jiw306",
"pmcid": "PMC5021232",
"issn": "0022-1899",
"publisher": "Oxford University Press",
"publication": "Journal of Infectious Diseases",
"publication_date": "2016-10-01",
"series_number": "7",
"volume": "214",
"issue": "7",
"pages": "1092-1104"
},
{
"id": "authors:06yvg-6ev90",
"collection": "authors",
"collection_id": "06yvg-6ev90",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161006-142747894",
"type": "article",
"title": "Enantioconvergent catalysis",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-Justin-T"
},
{
"family_name": "Moore",
"given_name": "Jared T.",
"clpid": "Moore-Jared-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioconvergent catalytic process has the potential to convert a racemic starting material to a single highly enantioenriched product with a maximum yield of 100%. Three mechanistically distinct approaches to effecting enantioconvergent catalysis are identified, and recent examples of each are highlighted. These processes are compared to related, non-enantioconvergent methods.",
"doi": "10.3762/bjoc.12.192",
"pmcid": "PMC5082454",
"issn": "1860-5397",
"publisher": "Beilstein-Institut",
"publication": "Beilstein Journal of Organic Chemistry",
"publication_date": "2016-09-16",
"volume": "12",
"pages": "2038-2045"
},
{
"id": "authors:28nhj-ger36",
"collection": "authors",
"collection_id": "28nhj-ger36",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160822-135959905",
"type": "article",
"title": "Iridium-Catalyzed Diastereo-, Enantio-, and Regioselective Allylic Alkylation with Prochiral Enolates",
"author": [
{
"family_name": "Hethcox",
"given_name": "J. Caleb",
"orcid": "0000-0002-7712-308X",
"clpid": "Hethcox-J-Caleb"
},
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Transition-metal-catalyzed asymmetric allylic alkylation of\nenolates is a powerful method for the formation of carbon\u2212\ncarbon bonds. Within this field, palladium-catalyzed allylic\nalkylation reactions have undoubtedly been the most studied.\nAside from limited cases, palladium catalysts preferentially\nform the linear substitution product through alkylation at the\nless-substituted terminus of the allylic electrophile (Scheme 1).\nHowever, in contrast to palladium, most other transition metals\n(e.g., Mo, W, Fe, Ru, Co, Rh, Ni, Pt, and Ir) have been shown\nto favor the construction of the branched product, with iridium\ncatalysts being some of the most efficient and selective. The\npotential application of these chiral, branched products to the\nsynthesis of natural products and biologically active compounds\nhas motivated the development of practical and reliable\ntransition-metal-catalyzed methods for their construction.",
"doi": "10.1021/acscatal.6b01886",
"pmcid": "PMC5481154",
"issn": "2155-5435",
"publisher": "American Chemical Society",
"publication": "ACS Catalysis",
"publication_date": "2016-09-02",
"series_number": "9",
"volume": "6",
"issue": "9",
"pages": "6207-6213"
},
{
"id": "authors:yhkqb-y4081",
"collection": "authors",
"collection_id": "yhkqb-y4081",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160919-073857486",
"type": "article",
"title": "Potassium tert-Butoxide-Catalyzed Dehydrogenative Cross-Coupling of Heteroarenes with Hydrosilanes",
"author": [
{
"family_name": "Toutov",
"given_name": "Anton A.",
"orcid": "0000-0002-6561-0462",
"clpid": "Toutov-A-A"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "A. 1-Methyl-2-(triethylsilyl)-1H-indole (2). An oven-dried 100-mL round-bottom Schlenk flask is equipped with a Teflon-coated magnetic stir bar (25 x 8 mm) and capped with a rubber septum (Note 1). The side arm of the flask is connected to Schlenk line and the flask is cooled to room temperature under vacuum and back-filled with nitrogen. Potassium tert-butoxide (1.34 g, 12.0 mmol, 0.2 equiv) is added to the flask under positive nitrogen flow (Notes 2 and 3), and then the flask is evacuated and back-filled with nitrogen three times. N-Methylindole (7.48 mL, 7.86 g, 60.0 mmol, 1.0 equiv) and triethylsilane (28.6 mL, 20.82 g, 179.5 mmol, 3.0 equiv) are added sequentially via syringe through the septum, resulting in a yellow heterogeneous mixture (Figure 1). After the septum is replaced with a glass stopper (Note 4), the reaction mixture is degassed (Note 5) and stirred at 45 \u00baC for 76 h (Note 6), resulting in a dark purple solution. The heating bath is removed and the reaction mixture is allowed to cool to ambient temperature (~25 \u00baC), then anhydrous diethyl ether (30 mL) is added slowly while stirring (Note 7).",
"doi": "10.15227/orgsyn.093.0263",
"issn": "0078-6209",
"publisher": "Organic Syntheses, Inc.",
"publication": "Organic Syntheses",
"publication_date": "2016-08-26",
"volume": "93",
"pages": "263-271"
},
{
"id": "authors:49y03-9rw06",
"collection": "authors",
"collection_id": "49y03-9rw06",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160725-104304872",
"type": "article",
"title": "Ni-Catalyzed Enantioselective C-Acylation of \u03b1-Substituted Lactams",
"author": [
{
"family_name": "Hayashi",
"given_name": "Masaki",
"clpid": "Hayashi-Masaki"
},
{
"family_name": "Bachman",
"given_name": "Shoshana",
"clpid": "Bachman-Shoshana"
},
{
"family_name": "Hashimoto",
"given_name": "Satoshi",
"clpid": "Hashimoto-Satoshi"
},
{
"family_name": "Eichman",
"given_name": "Chad C.",
"orcid": "0000-0002-8427-2358",
"clpid": "Eichman-Chad-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A new strategy for catalytic enantioselective C-acylation to generate \u03b1-quaternary-substituted lactams is reported. Ni-catalyzed three-component coupling of lactam enolates, benzonitriles, and aryl halides produces \u03b2-imino lactams that then afford \u03b2-keto lactams by acid hydrolysis. Use of a readily available Mandyphos-type ligand and addition of LiBr enable the construction of quaternary stereocenters on \u03b1-substituted lactams to form \u03b2-keto lactams in up to 94% ee.",
"doi": "10.1021/jacs.6b02120",
"pmcid": "PMC4963289",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2016-07-27",
"series_number": "29",
"volume": "138",
"issue": "29",
"pages": "8997-9000"
},
{
"id": "authors:by1kn-tmx24",
"collection": "authors",
"collection_id": "by1kn-tmx24",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160919-074608608",
"type": "article",
"title": "Preparation of 1,5-Dioxaspiro[5.5]undecan-3-one",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Smith",
"given_name": "Russell C.",
"clpid": "Smith-Russell-C"
},
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Estipona",
"given_name": "Benzi I.",
"clpid": "Estipona-Benzi-I"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A. 3-Amino-3-(hydroxymethyl)-1,5-dioxaspiro[5.5]undecane. A 1-L single-necked, round-bottomed flask is equipped with an egg-shaped, Teflon\u00ae-coated magnetic stirring bar (3.5 cm x 1.5 cm), capped with a rubber septum, flame-dried under vacuum, and cooled under an argon atmosphere (Note 1). After cooling to ambient temperature (21-23 \u00b0C), to the flask is added anhydrous N,N-dimethylformamide (DMF, 365 mL, 0.78 M) via cannula. Subsequently, tris(hydroxymethyl)aminomethane hydrochloride (45.0 g, 286 mmol, 1.00 equiv) (Note 2 and 3) is added in a single portion as white crystalline solid. The reaction vessel is immediately resealed with a rubber septum under inert atmosphere and stirring is commenced (Figure 1). To this white suspension is added 1,1-dimethoxycyclohexane (50.0 mL, 47.4 g, 329 mmol, 1.15 equiv) via syringe in one portion (Note 4). Lastly, to the off-white slurry is added para-toluenesulfonic acid monohydrate (p-TsOH\u2022H2O, 1.63 g, 8.57 mmol, 0.03 equiv) as a solid in one portion quickly, immediately replacing the rubber septum to maintain an inert atmosphere.",
"doi": "10.15227/orgsyn.093.0210",
"pmcid": "PMC5514842",
"issn": "2333-3553",
"publisher": "Organic Syntheses, Inc.",
"publication": "Organic Syntheses",
"publication_date": "2016-07-21",
"volume": "93",
"pages": "210-227"
},
{
"id": "authors:s77yz-b4986",
"collection": "authors",
"collection_id": "s77yz-b4986",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160707-080125930",
"type": "article",
"title": "Catalytic enantioselective total synthesis of (+)-eucomic acid",
"author": [
{
"family_name": "Estipona",
"given_name": "Benzi I.",
"clpid": "Estipona-Benzi-I"
},
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-Beau-P"
},
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic enantioselective synthesis of (+)-eucomic acid is reported. A palladium-catalyzed asymmetric allylic alkylation is employed to access the chiral tetrasubstituted \u03b1-hydroxyacid moiety found in the natural product. The protecting group strategy was investigated, and a protecting group manipulation was made without any appreciable deleterious effects in the allylic alkylation reaction. Non-natural (+)-eucomic acid is synthesized in a longest linear sequence of 13 steps.",
"doi": "10.1016/j.tet.2016.02.059",
"pmcid": "PMC4986999",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2016-06-30",
"series_number": "26",
"volume": "72",
"issue": "26",
"pages": "3707-3712"
},
{
"id": "authors:61hxb-8eg11",
"collection": "authors",
"collection_id": "61hxb-8eg11",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160707-090355308",
"type": "article",
"title": "Tetrahedron Young Investigator Award ~ 2016",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Martin",
"given_name": "Stephen",
"clpid": "Martin-S"
}
],
"abstract": "The Executive Board of Directors for Tetrahedron Publications is pleased to recognize the outstanding achievements of Professor Neil K. Garg of the University of California, Los Angeles (UCLA) and has awarded him a Tetrahedron Young Investigator Award in recognition of his exceptional creativity and contributions to the field of organic synthesis, especially for the development and application of novel methods and strategies for the synthesis of complex natural products. Professor Garg will present his award address at the Tetrahedron Symposium held in Sitges, Spain in June 2016. To honor and commemorate his receipt of this award, this special Symposium-in-Print entitled, New Reactions and Methods and Their Applications to Complex Molecule Synthesis has been organized. We are grateful to the contributors to this issue for their outstanding accomplishments that have led to the production of this unique issue and congratulate Professor Garg on this honor.",
"doi": "10.1016/j.tet.2016.04.026",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2016-06-30",
"series_number": "26",
"volume": "72",
"issue": "26",
"pages": "iii"
},
{
"id": "authors:c3vee-hsb41",
"collection": "authors",
"collection_id": "c3vee-hsb41",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160609-145221780",
"type": "article",
"title": "Synthesis of Aryl Ketoamides via Aryne Insertion into Imides",
"author": [
{
"family_name": "Wright",
"given_name": "Austin C.",
"clpid": "Wright-A-C"
},
{
"family_name": "Haley",
"given_name": "Christopher K.",
"clpid": "Haley-C-K"
},
{
"family_name": "Lapointe",
"given_name": "Guillaume",
"clpid": "Lapointe-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An insertion of arenes into both imides and anhydrides via reactive aryne intermediates is presented. The reaction is performed under exceptionally mild conditions, and the corresponding ketoamide products are amenable to derivatization to deliver a variety of synthetically useful motifs such as quinolones, indoles, and ketoanilines.",
"doi": "10.1021/acs.orglett.6b00994",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2016-06-17",
"series_number": "12",
"volume": "18",
"issue": "12",
"pages": "2793-2795"
},
{
"id": "authors:5ev3g-jv937",
"collection": "authors",
"collection_id": "5ev3g-jv937",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160510-141655234",
"type": "article",
"title": "Nickel-Catalyzed Intramolecular C\u2212O Bond Formation: Synthesis of Cyclic Enol Ethers",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Doi",
"given_name": "Ryohei",
"orcid": "0000-0001-8285-0209",
"clpid": "Doi-Ryohei"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An efficient and exceptionally mild intramolecular nickel-catalyzed carbon\u2013oxygen bond-forming reaction between vinyl halides and primary, secondary, and tertiary alcohols has been achieved. Zinc powder was found to be an essential additive for obtaining high catalyst turnover and yields. This operationally simple method allows direct access to cyclic vinyl ethers in high yields in a single step.",
"doi": "10.1002/anie.201601991",
"pmcid": "PMC4985346",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2016-06-15",
"series_number": "26",
"volume": "55",
"issue": "26",
"pages": "7437-7440"
},
{
"id": "authors:hq18s-gka95",
"collection": "authors",
"collection_id": "hq18s-gka95",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160202-091959130",
"type": "article",
"title": "Synthetic Applications and Methodological Developments of Donor-Acceptor Cyclopropanes and Related Compounds",
"author": [
{
"family_name": "O'Connor",
"given_name": "Nicholas R.",
"clpid": "O'Connor-Nicholas-R"
},
{
"family_name": "Wood",
"given_name": "John L.",
"clpid": "Wood-John-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Donor-acceptor cyclopropanes are convenient precursors to reactive and versatile 1,3-dipoles, and have found application in the synthesis of a variety of carbo- and heterocyclic scaffolds. This perspective review details our laboratory's use of donor-acceptor cyclopropanes as intermediates toward the total synthesis of various natural products. We also discuss our work in the development of novel cycloadditions and rearrangements of donor-acceptor cyclopropanes and aziridines, as well as an example of an aryne insertion proceeding via fragmentation of a transient donor-acceptor cyclobutane.",
"doi": "10.1002/ijch.201500089",
"pmcid": "PMC6527366",
"issn": "0021-2148",
"publisher": "Wiley-VCH",
"publication": "Israel Journal of Chemistry",
"publication_date": "2016-06",
"series_number": "6-7",
"volume": "56",
"issue": "6-7",
"pages": "431-444"
},
{
"id": "authors:dpacw-dp919",
"collection": "authors",
"collection_id": "dpacw-dp919",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160502-084148448",
"type": "article",
"title": "A mild and efficient approach to enantioenriched \u03b1-hydroxyethyl \u03b1,\u03b2-unsaturated \u03b4-lactams",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A straightforward approach toward enantioenriched \u03b1-substituted \u03b1,\u03b2-unsaturated \u03b4-lactams is described. Although a considerable number of approaches toward \u03b1,\u03b2-unsaturated \u03b4-lactams have been reported, there are relatively few examples of enantioenriched \u03b1,\u03b4-disubstituted \u03b1,\u03b2-unsaturated \u03b4-lactams formation. The \u03b4-stereocenter was formed by addition of allylmagnesium bromide to an N-tert-butylsulfinyl imine. The \u03b1,\u03b2-unsaturated \u03b4-lactam was furnished by ring-closing metathesis. Although Baylis\u2013Hillman chemistry failed on this cyclic compound, introduction of the hydroxyethyl group prior to ring-closing metathesis was successful. A Baylis\u2013Hillman reaction was used to introduce the substituent at the \u03b1-position of the \u03b1,\u03b2-unsaturated lactam.",
"doi": "10.1016/j.tetlet.2016.04.022",
"pmcid": "PMC4864989",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2016-05-25",
"series_number": "21",
"volume": "57",
"issue": "21",
"pages": "2233-2235"
},
{
"id": "authors:vjdr7-5ty06",
"collection": "authors",
"collection_id": "vjdr7-5ty06",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160427-092037065",
"type": "article",
"title": "Enantioselective \u03b3-Alkylation of \u03b1,\u03b2-Unsaturated Malonates and Ketoesters by a Sequential Ir-Catalyzed Asymmetric Allylic Alkylation/Cope Rearrangement",
"author": [
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Okamoto",
"given_name": "Noriko",
"clpid": "Okamoto-Noriko"
},
{
"family_name": "Alexy",
"given_name": "Eric J.",
"orcid": "0000-0002-2971-9698",
"clpid": "Alexy-Eric-J"
},
{
"family_name": "Hong",
"given_name": "Allen Y.",
"orcid": "0000-0002-4691-548X",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Tran",
"given_name": "Kristy",
"clpid": "Tran-Kristy"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic, enantioselective \u03b3-alkylation of \u03b1,\u03b2-unsaturated malonates and ketoesters is reported. This strategy entails a highly regio- and enantioselective iridium-catalyzed \u03b1-alkylation of an extended enolate, and a subsequent translocation of chirality to the \u03b3-position via a Cope rearrangement.",
"doi": "10.1021/jacs.6b02153",
"pmcid": "PMC5497580",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2016-04-27",
"series_number": "16",
"volume": "138",
"issue": "16",
"pages": "5234-5237"
},
{
"id": "authors:21deg-34f34",
"collection": "authors",
"collection_id": "21deg-34f34",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160425-132914132",
"type": "article",
"title": "Enantioselective Synthesis of Caprolactam and Enone Precursors to the Heterocyclic DEFG Ring System of Zoanthenol",
"author": [
{
"family_name": "Bagdanoff",
"given_name": "Jeffrey T.",
"clpid": "Bagdanoff-Jeffrey-T"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-Douglas-C"
},
{
"family_name": "Stockdill",
"given_name": "Jennifer L.",
"orcid": "0000-0003-4238-6530",
"clpid": "Stockdill-Jennifer-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The enantioselective synthesis of both caprolactam and enone synthons for the DEFG ring system of zoanthenol are described. The evolution of this approach proceeds first through a synthesis using the chiral pool as a starting point. Challenges in protecting-group strategy led to the modification of this approach beginning with (\u00b1)-glycidol. Ultimately, an efficient approach was developed by employing an asymmetric hetero-Diels\u2013Alder reaction. The caprolactam building block can be converted by an interesting selective Grignard addition into the corresponding enone synthon. Addition of a model alkyne provides support for the late-stage addition of a hindered alkyne to the caprolactam building block.",
"doi": "10.1002/ejoc.201600223",
"pmcid": "PMC5225988",
"issn": "1434-193X",
"publisher": "Wiley-VCH Verlag",
"publication": "European Journal of Organic Chemistry",
"publication_date": "2016-04",
"series_number": "12",
"volume": "2016",
"issue": "12",
"pages": "2101-2104"
},
{
"id": "authors:pcsck-8hs18",
"collection": "authors",
"collection_id": "pcsck-8hs18",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160201-141332316",
"type": "article",
"title": "Development of a simple system for the oxidation of electron-rich diazo compounds to ketones",
"author": [
{
"family_name": "O'Connor",
"given_name": "Nicholas R.",
"clpid": "O'Connor-N-R"
},
{
"family_name": "Bolgar",
"given_name": "Peter",
"clpid": "Bolgar-P"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Mild heating of diazo compounds in DMSO furnishes ketone products in moderate to excellent yields. The\nreaction is particularly effective on electron-rich substrates and exhibits high chemoselectivity, allowing\nfor the use of diazo compounds containing additional oxidation-prone functional groups. This straightforward\nprotocol offers an alternate route to synthetically useful \u0251-ketoesters from readily available aryl diazoacetates.",
"doi": "10.1016/j.tetlet.2016.01.020",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2016-02-24",
"series_number": "8",
"volume": "57",
"issue": "8",
"pages": "849-851"
},
{
"id": "authors:fehkp-ha224",
"collection": "authors",
"collection_id": "fehkp-ha224",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160119-141029568",
"type": "article",
"title": "Total Synthesis and Characterization of 7-Hypoquinuclidonium Tetrafluoroborate and 7-Hypoquinuclidone BF_3 Complex",
"author": [
{
"family_name": "Liniger",
"given_name": "Marc",
"orcid": "0000-0002-4273-2942",
"clpid": "Liniger-Marc"
},
{
"family_name": "VanderVelde",
"given_name": "David G.",
"orcid": "0000-0002-2907-0366",
"clpid": "VanderVelde-D-G"
},
{
"family_name": "Takase",
"given_name": "Michael K.",
"orcid": "0000-0001-8365-3645",
"clpid": "Takase-Michael-K"
},
{
"family_name": "Shahgholi",
"given_name": "Mona",
"clpid": "Shahgholi-Mona"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Derivatives of the fully twisted bicyclic amide 7-hypoquinuclidone are synthesized using a Schmidt\u2013Aub\u00e9 reaction. Their structures were unambiguously confirmed by X-ray diffraction analysis and extensive spectroscopic characterization. Furthermore, the stability and chemical reactivity of these anti-Bredt amides are investigated. 7-Hypoquinuclidonium tetrafluoroborate is shown to decompose to a unique nitrogen bound amide\u2013BF_3 complex of 7-hypoquinuclidone under anhydrous conditions and to react instantaneously with water making it one of the most reactive amides known to date.",
"doi": "10.1021/jacs.5b11750",
"pmcid": "PMC4878439",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2016-01-27",
"series_number": "3",
"volume": "138",
"issue": "3",
"pages": "969-974"
},
{
"id": "authors:j66fk-evs29",
"collection": "authors",
"collection_id": "j66fk-evs29",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160112-074404722",
"type": "article",
"title": "Production and Fate of C_4 Dihydroxycarbonyl Compounds from Isoprene Oxidation",
"author": [
{
"family_name": "Bates",
"given_name": "Kelvin H.",
"orcid": "0000-0001-7544-9580",
"clpid": "Bates-K-H"
},
{
"family_name": "Nguyen",
"given_name": "Tran B.",
"clpid": "Nguyen-Tran-B"
},
{
"family_name": "Teng",
"given_name": "Alex P.",
"clpid": "Teng-Alex-P"
},
{
"family_name": "Crounse",
"given_name": "John D.",
"orcid": "0000-0001-5443-729X",
"clpid": "Crounse-J-D"
},
{
"family_name": "Kjaergaard",
"given_name": "Henrik G.",
"orcid": "0000-0002-7275-8297",
"clpid": "Kjaergaard-H-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Seinfeld",
"given_name": "John H.",
"orcid": "0000-0003-1344-4068",
"clpid": "Seinfeld-J-H"
},
{
"family_name": "Wennberg",
"given_name": "Paul O.",
"orcid": "0000-0002-6126-3854",
"clpid": "Wennberg-P-O"
}
],
"abstract": "Isoprene epoxydiols (IEPOX) are formed in high yield as second-generation products of atmospheric isoprene oxidation in pristine (low-NO) environments. IEPOX has received significant attention for its ability to form secondary organic aerosol, but the fate of IEPOX in the gas phase, and those of its oxidation products, remains largely unexplored. In this study, three dihydroxycarbonyl compounds with molecular formula of C_4H_8O_3, putative products of IEPOX oxidation, are synthesized to determine their isomer-specific yields from IEPOX. We find that 3,4-dihydroxy-2-butanone (DHBO) comprises 43% and 36% of the products from cis- and trans-\u03b2-IEPOX, respectively, and is by far the most abundant C_4H_8O_3 dihydroxycarbonyl compound produced by this mechanism. OH is found to react with DHBO with a rate coefficient of 1.10 \u00d7 10^(\u201311) cm^3 molecule^(\u20131) s^(\u20131) at 297 K, forming two hydroxydicarbonyl compounds that share the molecular formula C_4H_6O_3 with unitary yield. The results of this study are compared with field observations and used to propose a multigenerational mechanism of IEPOX oxidation. Finally, global simulations using GEOS-Chem, a chemical transport model, show that the C_4H_8O_3 dihydroxycarbonyl compounds and their oxidation products are widespread in the atmosphere and estimate annual global production of C_4H_8O_3 dihydroxycarbonyls to be 54 Tg\u202fy^(\u20131), primarily as DHBO.",
"doi": "10.1021/acs.jpca.5b10335",
"issn": "1089-5639",
"publisher": "American Chemical Society",
"publication": "Journal of Physical Chemistry A",
"publication_date": "2016-01-14",
"series_number": "1",
"volume": "120",
"issue": "1",
"pages": "106-117"
},
{
"id": "authors:j0p0t-dwr78",
"collection": "authors",
"collection_id": "j0p0t-dwr78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160111-102110097",
"type": "article",
"title": "Label-free detection of single nanoparticles and biological molecules using microtoroid optical resonators",
"author": [
{
"family_name": "Su",
"given_name": "Judith",
"clpid": "Su-Judith"
},
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Single-molecule detection is one of the fundamental challenges of modern biology. Such experiments often use labels that can be expensive, difficult to produce, and for small analytes, might perturb the molecular events being studied. Analyte size plays an important role in determining detectability. Here we use laser-frequency locking in the context of sensing to improve the signal-to-noise ratio of microtoroid optical resonators to the extent that single nanoparticles 2.5 nm in radius, and 15.5 kDa molecules are detected in aqueous solution, thereby bringing these detectors to the size limits needed for detecting the key macromolecules of the cell. Our results, covering several orders of magnitude of particle radius (100 nm to 2 nm), agree with the 'reactive' model prediction for the frequency shift of the resonator upon particle binding. This confirms that the main contribution of the frequency shift for the resonator upon particle binding is an increase in the effective path length due to part of the evanescent field coupling into the adsorbed particle. We anticipate that our results will enable many applications, including more sensitive medical diagnostics and fundamental studies of single receptor\u2013ligand and protein\u2013protein interactions in real time.",
"doi": "10.1038/lsa.2016.1",
"pmcid": "PMC6059845",
"issn": "2047-7538",
"publisher": "Nature Publishing Group",
"publication": "Light: Science and Applications",
"publication_date": "2016-01",
"series_number": "1",
"volume": "5",
"issue": "1",
"pages": "Art. No. e16001"
},
{
"id": "authors:4ck84-zg430",
"collection": "authors",
"collection_id": "4ck84-zg430",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170919-091408635",
"type": "book_section",
"title": "Asymmetric Synthesis of Quaternary Stereocenters via Metal Enolates",
"book_title": "PATAI'S Chemistry of Functional Groups",
"author": [
{
"family_name": "Korch",
"given_name": "Katerina M.",
"clpid": "Korch-K-M"
},
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-S-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"contributor": [
{
"family_name": "Patai",
"given_name": "Saul",
"clpid": "Patai-S"
},
{
"family_name": "Rappoport",
"given_name": "Zvi",
"clpid": "Rappoport-Z"
}
],
"abstract": "The strategy of using chiral metal enolate intermediates in a diverse variety of asymmetric transformations has allowed the generation of quaternary stereocenter-bearing products that are otherwise difficult to access. Many classic transformations including aldol, Mannich, conjugate addition, alkylation, and pericyclic-type reactions, as well as allylic alkylation and \u03b1-arylation/alkenylation, have been adapted to proceed through chiral metal enolate intermediates, allowing the asymmetric synthesis of many complex products in both an intermolecular and intramolecular manner. These transformations have proven useful in the synthesis of natural products and may also be applied to the synthesis of novel pharmaceuticals and other compounds of interest in the future. This review includes work done up to and including the year 2014.",
"doi": "10.1002/9780470682531.pat0858",
"isbn": "9780470682531",
"publisher": "Wiley",
"place_of_publication": "Chichester",
"publication_date": "2016",
"pages": "1-85"
},
{
"id": "authors:vm1es-78r79",
"collection": "authors",
"collection_id": "vm1es-78r79",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151103-103452993",
"type": "article",
"title": "Catalytic C\u2013H bond silylation of aromatic heterocycles",
"author": [
{
"family_name": "Toutov",
"given_name": "Anton A.",
"orcid": "0000-0002-6561-0462",
"clpid": "Toutov-A-A"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Betz",
"given_name": "Kerry N.",
"orcid": "0000-0001-9118-5909",
"clpid": "Betz-K-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "This protocol describes a method for the direct silylation of the carbon\u2013hydrogen (C\u2013H) bond of aromatic heterocycles using inexpensive and abundant potassium tert-butoxide (KOt-Bu) as the catalyst. This catalytic cross-dehydrogenative coupling of simple hydrosilanes and various electron-rich aromatic heterocycles enables the synthesis of valuable silylated heteroarenes. The products thus obtained can be used as versatile intermediates, which facilitate the divergent synthesis of pharmaceutically relevant compound libraries from a single Si-containing building block. Moreover, a variety of complex Si-containing motifs, such as those produced by this protocol, are being actively investigated as next-generation therapeutic agents, because they can have improved pharmacokinetic properties compared with the original all-carbon drug molecules. Current competing methods for C\u2013H bond silylation tend to be incompatible with functionalities, such as Lewis-basic heterocycles, that are often found in pharmaceutical substances; this leaves de novo synthesis as the principal strategy for preparation of the target sila-drug analog. Moreover, competing methods tend to be limited in the scope of hydrosilane that can be used, which restricts the breadth of silicon-containing small molecules that can be accessed. The approach outlined in this protocol enables the chemoselective and regioselective late-stage silylation of small heterocycles, including drugs and drug derivatives, with a broad array of hydrosilanes in the absence of precious metal catalysts, stoichiometric reagents, sacrificial hydrogen acceptors or high temperatures. Moreover, H_2 is the only by-product generated. The procedure normally requires 48\u201375 h to be completed.",
"doi": "10.1038/nprot.2015.118",
"issn": "1754-2189",
"publisher": "Nature Publishing Group",
"publication": "Nature Protocols",
"publication_date": "2015-12",
"series_number": "12",
"volume": "10",
"issue": "12",
"pages": "1897-1903"
},
{
"id": "authors:bwr2h-wt704",
"collection": "authors",
"collection_id": "bwr2h-wt704",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151102-100307186",
"type": "article",
"title": "Palladium-Catalyzed Enantioselective Decarboxylative Allylic Alkylation of Cyclopentanones",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Loskot",
"given_name": "Steven A.",
"clpid": "Loskot-Steven-A"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-Justin-T"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-Douglas-C"
},
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-Andrew-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first general method for the enantioselective construction of all-carbon quaternary centers on cyclopentanones by enantioselective palladium-catalyzed decarboxylative allylic alkylation is described. Employing the electronically modified (S)-(p-CF_3)_3-t-BuPHOX ligand, \u03b1-quaternary cyclopentanones were isolated in yields up to >99% with ee's up to 94%. Additionally, in order to facilitate large-scale application of this method, a low catalyst loading protocol was employed, using as little as 0.15 mol % Pd, furnishing the product without any loss in ee.",
"doi": "10.1021/acs.orglett.5b02376",
"pmcid": "PMC4640231",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2015-11-06",
"series_number": "21",
"volume": "17",
"issue": "21",
"pages": "5160-5163"
},
{
"id": "authors:m0k7j-kqf73",
"collection": "authors",
"collection_id": "m0k7j-kqf73",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150807-083400322",
"type": "article",
"title": "Palladium-Catalyzed Decarbonylative Dehydration for the Synthesis of \u03b1-Vinyl Carbonyl Compounds and Total Synthesis of (\u2212)-Aspewentins A, B, and C",
"author": [
{
"family_name": "Liu",
"given_name": "Yiyang",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-Scott-C"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The direct \u03b1-vinylation of carbonyl compounds to form a quaternary stereocenter is a challenging transformation. It was discovered that \u03b4-oxocarboxylic acids can serve as masked vinyl compounds and be unveiled by palladium-catalyzed decarbonylative dehydration. The carboxylic acids are readily available through enantioselective acrylate addition or asymmetric allylic alkylation. A variety of \u03b1-vinyl quaternary carbonyl compounds are obtained in good yields, and an application in the first enantioselective total synthesis of (\u2212)-aspewentins A, B, and C is demonstrated.",
"doi": "10.1002/anie.201505161",
"pmcid": "PMC4686263",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2015-09-28",
"series_number": "40",
"volume": "54",
"issue": "40",
"pages": "11800-11803"
},
{
"id": "authors:v8mk3-yc236",
"collection": "authors",
"collection_id": "v8mk3-yc236",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150608-130804663",
"type": "article",
"title": "Construction of Tertiary Chiral Centers by Pd-catalyzed Asymmetric Allylic Alkylation of Prochiral Enolate Equivalents",
"author": [
{
"family_name": "Kita",
"given_name": "Yusuke",
"orcid": "0000-0003-2455-7076",
"clpid": "Kita-Yusuke"
},
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Okamoto",
"given_name": "Noriko",
"clpid": "Okamoto-Noriko"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The palladium-catalyzed decarboxylative allylic alkylation of enol carbonates derived from lactams and ketones is described. Employing these substrates with an electronically tuned Pd catalyst system trisubstituted chiral centers are produced. These stereocenters have been previously challenging to achieve using Pd complex/chiral P\u2013N ligand systems.",
"doi": "10.1016/j.tet.2015.05.092",
"pmcid": "PMC4528676",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2015-09-16",
"series_number": "37",
"volume": "71",
"issue": "37",
"pages": "6349-6353"
},
{
"id": "authors:sn6k2-ywg71",
"collection": "authors",
"collection_id": "sn6k2-ywg71",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150807-090520766",
"type": "article",
"title": "Palladium(II)-Catalyzed Allylic C-H Oxidation of Hindered Substrates Featuring Tunable Selectivity Over Extent of Oxidation",
"author": [
{
"family_name": "Xing",
"given_name": "Xiangyou",
"orcid": "0000-0002-2456-0825",
"clpid": "Xing-Xiangyou"
},
{
"family_name": "O'Connor",
"given_name": "Nicholas R.",
"clpid": "O'Connor-N-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The use of Oxone and a palladium(II) catalyst enables the efficient allylic C-H oxidation of sterically hindered \u03b1-quaternary lactams which are unreactive under known conditions for similar transformations. This simple, safe, and effective system for C-H activation allows for unusual tunable selectivity between a two-electron oxidation to the allylic acetates and a four-electron oxidation to the corresponding enals, with the dominant product depending on the presence or absence of water. The versatile synthetic utility of both the allylic acetate and enal products accessible through this methodology is also demonstrated.",
"doi": "10.1002/anie.201504007",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2015-09-14",
"series_number": "38",
"volume": "54",
"issue": "38",
"pages": "11186-11190"
},
{
"id": "authors:4khq6-9ss54",
"collection": "authors",
"collection_id": "4khq6-9ss54",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141208-091240402",
"type": "article",
"title": "Synthesis of Diverse \u03b2-Quaternary Ketones via Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Cyclic Enones",
"author": [
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Goodman",
"given_name": "Emmett D.",
"clpid": "Goodman-E-D"
},
{
"family_name": "Kikushima",
"given_name": "Kotaro",
"clpid": "Kikushima-Kotaro"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-A-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development and optimization of a palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic enone conjugate acceptors is described. These reactions employ air-stable and readily-available reagents in an operationally simple and robust transformation that yields \u03b2-quaternary ketones in high yields and enantioselectivities. Notably, the reaction itself is highly tolerant of atmospheric oxygen and moisture and therefore does not require the use of dry or deoxygenated solvents, specially purified reagents, or an inert atmosphere. The ring size and \u03b2-substituent of the enone are highly variable, and a wide variety of \u03b2-quaternary ketones can be synthesized. More recently, the use of NH_4PF_6 has further expanded the substrate scope to include heteroatom-containing arylboronic acids and \u03b2-acyl enone substrates.",
"doi": "10.1016/j.tet.2014.11.048",
"pmcid": "PMC4598955",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2015-09-02",
"series_number": "35",
"volume": "71",
"issue": "35",
"pages": "5781-5792"
},
{
"id": "authors:p2x3v-6q964",
"collection": "authors",
"collection_id": "p2x3v-6q964",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150728-085152188",
"type": "article",
"title": "Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to \u03b1,\u03b2-Unsaturated Cyclic Electrophiles",
"author": [
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-Jeffrey-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "This account describes our laboratory's efforts in the development of a palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic conjugate acceptors. Specifically, we highlight the study of this transformation in the following areas: (a) construction of all-carbon quaternary stereocenters, (b) elucidation of the reaction mechanism, (c) addition to heterocyclic acceptors to generate tertiary stereocenters, and (d) application in the synthesis of natural products.",
"doi": "10.1021/acs.oprd.5b00169",
"pmcid": "PMC4896742",
"issn": "1083-6160",
"publisher": "American Chemical Society",
"publication": "Organic Process Research & Development",
"publication_date": "2015-08-21",
"series_number": "8",
"volume": "19",
"issue": "8",
"pages": "974-981"
},
{
"id": "authors:wj4az-56k91",
"collection": "authors",
"collection_id": "wj4az-56k91",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150824-143923597",
"type": "article",
"title": "Preparation of (S)-tert-ButylPyOx and Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids",
"author": [
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-Jeffrey-C"
},
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"orcid": "0000-0001-5682-8569",
"clpid": "Shockley-Samantha-E"
},
{
"family_name": "Wiesenfeldt",
"given_name": "Mario P.",
"clpid": "Wiesenfeldt-Mario-P"
},
{
"family_name": "Shimizu",
"given_name": "Hideki",
"clpid": "Shimizu-Hideki"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A. (S)-N-(1-Hydroxy-3,3-dimethylbutan-2-yl)picolinamide (2). A 1 L one-necked round-bottomed flask equipped with a 3.0 cm x 1.4 cm, egg-shaped, Teflon-coated magnetic stirring bar is sealed with a septum and connected via needle adapter to a two-tap Schlenk adapter attached to an oil bubbler and a nitrogen/vacuum manifold (Note 1). The flask is dried with a heat gun under vacuum and cooled under a stream of nitrogen. The flask is charged with 2-picolinic acid (1) (6.15 g, 50.0 mmol, 1.00 equiv) (Note 2), evacuated and back-filled with nitrogen three times, then charged with dichloromethane (300 mL, 0.17 M) (Note 3) and N-methylmorpholine (7.59 g, 8.25 mL, 75.0 mmol, 1.50 equiv). The flask is cooled in an ice/water bath and iso-butylchloroformate (6.86 mL, 7.17 g, 52.5 mmol, 1.05 equiv) is added dropwise over 30 min by syringe pump. The reaction mixture is stirred for an additional 30 min while remaining submerged in the ice/water bath. A separate 100 mL one-necked round-bottomed flask is sealed with a septum and connected via needle adapter to the two-tap Schlenk adapter and manifold, dried with a heat gun under vacuum, and allowed to cool under a stream of nitrogen. This flask is charged with (S)-tert-leucinol (6.45 g, 55.0 mmol, 1.10 equiv), dichloromethane (40 mL), and N-methylmorpholine (6.07 mL, 5.56 g, 55.0 mmol, 1.10 equiv). The resulting clear solution is taken up in a syringe and transferred dropwise using a syringe pump over the course of 1 h to the stirring reaction mixture in the ice/water bath. The cooling bath is removed, and the pale gold colored reaction mixture is stirred for an additional 6 h at 23 \u00b0C. Upon consumption of starting material (Note 4), the mixture is quenched at ambient temperature with a single addition of an aqueous solution of saturated NH_4Cl (50 mL), diluted with additional H_2O (25 mL), and transferred into a 1 L separatory funnel. The phases are separated, and the aqueous phase is extracted with CH_2Cl_2 (3 x 100 mL). The combined organic phases are washed with an aqueous solution of saturated NaHCO_3 (1 x 50 mL) and brine (1 x 50 mL). The combined organic phases are dried over Na_2SO_4 (10 g, 15 min while agitating), filtered through a M pore glass frit, and concentrated by rotary evaporation (28 \u00b0C, 15 mmHg). Excess N-methylmorpholine is further removed by placing the crude residue under high vacuum (< 12 mmHg, 12 h) to provide a pale red solid (Note 5). The crude residue is dissolved in 10 mL of acetone and purified via silica gel flash chromatography (Note 6). The combined product-containing fractions are concentrated by rotary evaporation (40 \u00b0C, 15 mmHg) to yield a solid, which is dried under high vacuum (< 12 mmHg, 12 h) to afford (S)-N-(1-hydroxy-3,3-dimethylbutan-2-yl)picolinamide (2) as a white amorphous solid (9.88-9.95 g, 44.4-44.8 mmol, 89-90% yield) (Note 7).",
"doi": "10.15227/orgsyn.092.0247",
"pmcid": "PMC6499391",
"issn": "2333-3553",
"publisher": "Organic Syntheses, Inc.",
"publication": "Organic Syntheses",
"publication_date": "2015-08-07",
"volume": "92",
"pages": "247-266"
},
{
"id": "authors:s2rem-w2g25",
"collection": "authors",
"collection_id": "s2rem-w2g25",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150706-103427588",
"type": "article",
"title": "Synthesis and exploration of electronically modified\n (R)-5,5-dimethyl-(p-CF\u2083)\u2083-i-PrPHOX in palladium-catalyzed\n enantio- and diastereoselective allylic alkylation: a practical alternative to (R)-(p-CF\u2083)\u2083-t-BuPHOX",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The synthesis of the novel electronically modified phosphinooxazoline (PHOX) ligand, (R)-5,5-dimethyl-(p-CF\u2083)\u2083-i-PrPHOX, is described. The utility of this PHOX ligand is explored in both enantio- and diastereoselective palladium-catalyzed allylic alkylations. These investigations prove (R)-5,5-dimethyl-(p-CF\u2083)\u2083-i-PrPHOX to be an effective and cost-efficient alternative to electronically modified PHOX ligands derived from the prohibitively expensive (R)-t-leucine.",
"doi": "10.1016/j.tetlet.2015.06.039",
"pmcid": "PMC4524747",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2015-08-05",
"series_number": "32",
"volume": "56",
"issue": "32",
"pages": "4670-4673"
},
{
"id": "authors:hs080-27p82",
"collection": "authors",
"collection_id": "hs080-27p82",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150720-144300390",
"type": "article",
"title": "An Efficient Protocol for the Palladium-Catalyzed Asymmetric Decarboxylative Allylic Alkylation Using Low Palladium Concentrations and a Palladium(II) Precatalyst",
"author": [
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-Alexander-N"
},
{
"family_name": "Duquette",
"given_name": "Douglas C.",
"clpid": "Duquette-Douglas-C"
},
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-Robert-A-II"
},
{
"family_name": "Kim",
"given_name": "Kelly E.",
"orcid": "0000-0002-4132-2474",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Liniger",
"given_name": "Marc",
"orcid": "0000-0002-4273-2942",
"clpid": "Liniger-Marc"
},
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Enantioselective catalytic allylic alkylation for the synthesis of 2-alkyl-2-allylcycloalkanones and 3,3-disubstituted pyrrolidinones, piperidinones and piperazinones has been previously reported by our laboratory. The efficient construction of chiral all-carbon quaternary centers by allylic alkylation was previously achieved with a catalyst derived in situ from zero-valent palladium sources and chiral phosphinooxazoline (PHOX) ligands. We now report an improved reaction protocol with broad applicability among different substrate classes in industry-compatible reaction media using loadings of palladium(II) acetate as low as 0.075\u2005mol% and the readily available chiral PHOX ligands. The novel and highly efficient procedure enables facile scale-up of the reaction in an economical and sustainable fashion.",
"doi": "10.1002/adsc.201500253",
"pmcid": "PMC4811629",
"issn": "1615-4150",
"publisher": "Wiley",
"publication": "Advanced Synthesis and Catalysis",
"publication_date": "2015-07-06",
"series_number": "10",
"volume": "357",
"issue": "10",
"pages": "2238-2245"
},
{
"id": "authors:930b7-7qh86",
"collection": "authors",
"collection_id": "930b7-7qh86",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150615-081527494",
"type": "article",
"title": "Exceedingly Efficient Synthesis of (\u00b1)-Grandifloracin and Acylated Analogues",
"author": [
{
"family_name": "Bergner",
"given_name": "Magnus",
"clpid": "Bergner-M"
},
{
"family_name": "Duquette",
"given_name": "Douglas C.",
"clpid": "Duquette-D-C"
},
{
"family_name": "Chio",
"given_name": "Linda",
"clpid": "Chio-Linda"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A highly efficient regio- and stereoselective total synthesis of (\u00b1)-grandifloracin via a tandem dearomative epoxidation/spontaneous Diels\u2013Alder cyclodimerization from salicylic acid in only four steps is reported. The synthetic route allows for late-stage diversification of the core structure to give ready access to analogues of this promising agent against pancreatic cancer.",
"doi": "10.1021/acs.orglett.5b01292",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2015-06-19",
"series_number": "12",
"volume": "17",
"issue": "12",
"pages": "3008-3010"
},
{
"id": "authors:yg9jy-3wk48",
"collection": "authors",
"collection_id": "yg9jy-3wk48",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140930-130037903",
"type": "article",
"title": "Highly functionalized donor\u2013acceptor cyclopropanes applied toward the synthesis of the Melodinus alkaloids",
"author": [
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-R-A-II"
},
{
"family_name": "O'Connor",
"given_name": "Nicholas R.",
"clpid": "O'Connor-N-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A series of highly substituted vinylcyclopropanes were prepared and examined as reaction partners in a palladium-catalyzed (3 + 2) cycloaddition with nitrostyrenes. Described herein are our efforts to synthesize an elusive 1,1-divinylcyclopropane by several distinct approaches, and to apply surrogates of this fragment toward the synthesis of the Melodinus alkaloids.",
"doi": "10.1016/j.tetlet.2014.09.016",
"pmcid": "PMC4479304",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2015-06-03",
"series_number": "23",
"volume": "56",
"issue": "23",
"pages": "2983-2990"
},
{
"id": "authors:65v92-3gn55",
"collection": "authors",
"collection_id": "65v92-3gn55",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141110-091731285",
"type": "article",
"title": "Stereochemical evaluation of bis(phosphine) copper catalysts for the asymmetric alkylation of 3-bromooxindoles with \u03b1-arylated malonate esters",
"author": [
{
"family_name": "Lee",
"given_name": "Chung Whan",
"clpid": "Lee-Chung-Whan"
},
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An improved method for the asymmetric alkylation of 3-bromooxindoles with \u03b1-arylated malonate esters is described. The asymmetric alkylation demonstrated was achieved up to 70% ee utilizing a copper(II) bis(phosphine) complex.",
"doi": "10.1016/j.tet.2014.10.065",
"pmcid": "PMC4429905",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2015-06-03",
"series_number": "22",
"volume": "71",
"issue": "22",
"pages": "3666-3670"
},
{
"id": "authors:fk4p8-c3614",
"collection": "authors",
"collection_id": "fk4p8-c3614",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150302-135348269",
"type": "article",
"title": "Enantioselective Synthesis of Dialkylated N-Heterocycles by Palladium-Catalyzed Allylic Alkylation",
"author": [
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Jim\u00e9nez-Os\u00e9s",
"given_name": "Gonzalo",
"clpid": "Jim\u00e9nez-Os\u00e9s-G"
},
{
"family_name": "Wang",
"given_name": "Bo",
"clpid": "Wang-Bo"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-K-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The enantioselective synthesis of \u03b1-disubstituted N-heterocyclic carbonyl compounds has been accomplished using palladium-catalyzed allylic alkylation. These catalytic conditions enable access to various heterocycles, such as morpholinone, thiomorpholinone, oxazolidin-4-one, 1,2-oxazepan-3-one, 1,3-oxazinan-4-one, and structurally related lactams, all bearing fully substituted \u03b1-positions. Broad functional group tolerance was explored at the \u03b1-position in the morpholinone series. We demonstrate the utility of this method by performing various transformations on our useful products to readily access a number of enantioenriched compounds.",
"doi": "10.1021/ol503425t",
"pmcid": "PMC6410707",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2015-03-06",
"series_number": "5",
"volume": "17",
"issue": "5",
"pages": "1082-1085"
},
{
"id": "authors:0c7gd-5vv54",
"collection": "authors",
"collection_id": "0c7gd-5vv54",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150313-143109436",
"type": "article",
"title": "Mechanistic analysis of an asymmetric palladium-catalyzed conjugate addition of arylboronic acids to \u03b2-substituted cyclic enones",
"author": [
{
"family_name": "Boeser",
"given_name": "Cornelia L.",
"clpid": "Boeser-C-L"
},
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Taylor",
"given_name": "Buck L. H.",
"orcid": "0000-0002-6586-3865",
"clpid": "Taylor-B-L-H"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-K-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Zare",
"given_name": "Richard N.",
"orcid": "0000-0001-5266-4253",
"clpid": "Zare-R-N"
}
],
"abstract": "An asymmetric palladium-catalyzed conjugate addition reaction of arylboronic acids to enone substrates was investigated mechanistically. Desorption electrospray ionization coupled to mass spectrometry was used to identify intermediates of the catalytic cycle and delineate differences in substrate reactivity. Our findings provide evidence for the catalytic cycle proceeding through formation of an arylpalladium(II) cation, subsequent formation of an arylpalladium\u2013enone complex, and, ultimately, formation of the new C\u2013C bond. Reaction monitoring in both positive and negative ion modes revealed that 4-iodophenylboronic acid formed a relatively stable trimeric species under the reaction conditions.",
"doi": "10.1039/c4sc03337j",
"pmcid": "PMC4338963",
"issn": "2041-6520",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Science",
"publication_date": "2015-03-01",
"series_number": "3",
"volume": "6",
"issue": "3",
"pages": "1917-1922"
},
{
"id": "authors:hv3kb-mve45",
"collection": "authors",
"collection_id": "hv3kb-mve45",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150303-082954224",
"type": "article",
"title": "Selective syntheses of leuconolam, leuconoxine, and mersicarpine alkaloids from a common intermediate through regiocontrolled cyclizations by Staudinger reactions",
"author": [
{
"family_name": "Li",
"given_name": "Zining",
"clpid": "Li-Zining"
},
{
"family_name": "Geng",
"given_name": "Qian",
"clpid": "Geng-Qian"
},
{
"family_name": "Lv",
"given_name": "Zhe",
"clpid": "Lv-Zhe"
},
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-B-P"
},
{
"family_name": "Baba",
"given_name": "Katsuaki",
"clpid": "Baba-K"
},
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Liang",
"given_name": "Guangxin",
"clpid": "Liang-Guangxin"
}
],
"abstract": "Selective syntheses of leuconolam, leuconoxine, and mersicarpine alkaloids bearing distinctive core structures were achieved through Staudinger reactions using a common intermediate. In the key cyclization step, water functioned like a switch to control which core structure to produce. The chemistry allowed for selective syntheses of the group of alkaloids from a simple intermediate through straightforward chemical operations.",
"doi": "10.1039/C4QO00312H",
"pmcid": "PMC4333676",
"issn": "2052-4110",
"publisher": "Royal Society of Chemistry",
"publication": "Organic Chemistry Frontiers",
"publication_date": "2015-03-01",
"series_number": "3",
"volume": "2",
"issue": "3",
"pages": "236-240"
},
{
"id": "authors:v22cc-h9t61",
"collection": "authors",
"collection_id": "v22cc-h9t61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150302-110204535",
"type": "article",
"title": "Catalytic Enantioselective Construction of Quaternary Stereocenters: Assembly of Key Building Blocks for the Synthesis of Biologically Active Molecules",
"author": [
{
"family_name": "Liu",
"given_name": "Yiyang",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The ever-present demand for drugs with better efficacy and fewer side effects continually motivates scientists to explore the vast chemical space. Traditionally, medicinal chemists have focused much attention on achiral or so-called \"flat\" molecules. More recently, attention has shifted toward molecules with stereogenic centers since their three-dimensional structures represent a much larger fraction of the chemical space and have a number of superior properties compared with flat aromatic compounds. Quaternary stereocenters, in particular, add greatly to the three-dimensionality and novelty of the molecule. Nevertheless, synthetic challenges in building quaternary stereocenters have largely prevented their implementation in drug discovery. The lack of effective and broadly general methods for enantioselective formation of quaternary stereocenters in simple molecular scaffolds has prompted us to investigate new chemistry and develop innovative tools and solutions.\n\nIn this Account, we describe three approaches to constructing quaternary stereocenters: nucleophilic substitution of 3-halooxindoles, conjugate addition of boronic acids to cyclic enones, and allylic alkylation of enolates. In the first approach, malonic ester nucleophiles attack electrophilic 3-halooxindoles, mediated by a copper(II)-bisoxazoline catalyst. A variety of oxindoles containing a benzylic quaternary stereocenter can be accessed through this method. However, it is only applicable to the specialized 3,3-disubstituted oxindole system. To access benzylic quaternary stereocenters in a more general context, we turned our attention to the enantioselective conjugate addition of carbon nucleophiles to \u03b1,\u03b2-unsaturated carbonyl acceptors. We discovered that in the presence of catalytic palladium-pyridinooxazoline complex, arylboronic acids add smoothly to \u03b2-substituted cyclic enones to furnish ketones with a \u03b2-benzylic quaternary stereocenter in high yields and enantioselectivities. The reaction is compatible with a wide range of arylboronic acids, \u03b2-substituents, and ring sizes.\n\nAside from benzylic quaternary stereocenters, a more challenging motif is a quaternary stereocenter not adjacent to an aromatic group. Such centers represent more general structures in chemical space but are more difficult to form by asymmetric catalysis. To address this greater challenge, and motivated by the greater reward, we entered the field of palladium-catalyzed asymmetric allylic alkylation of prochiral enolate nucleophiles about a decade ago. On the basis of Tsuji's work, which solved the issue of positional selectivity for unsymmetrical ketones, we discovered that the phosphinooxazoline ligand effectively rendered this reaction enantioselective. Extensive investigations since then have revealed that the reaction exhibits broad scope and accepts a range of substrate classes, each with its unique advantage in synthetic applications. A diverse array of carbonyl compounds bearing \u03b1-quaternary stereocenters are obtained in excellent yields and enantioselectivities, and more possibilities have yet to be explored. As an alternative to palladium catalysis, we also studied iridium-catalyzed asymmetric allylic alkylations that generate vicinal quaternary and tertiary stereocenters in a single transformation. Overall, these methods provide access to small molecule building blocks with a single quaternary stereocenter, can be applied to various molecular scaffolds, and tolerate a wide range of functional groups. We envision that the chemistry reported in this Account will be increasingly useful in drug discovery and design.",
"doi": "10.1021/ar5004658",
"pmcid": "PMC6410712",
"issn": "0001-4842",
"publisher": "American Chemical Society",
"publication": "Accounts of Chemical Research",
"publication_date": "2015-03",
"series_number": "3",
"volume": "48",
"issue": "3",
"pages": "740-751"
},
{
"id": "authors:cvfqr-6b645",
"collection": "authors",
"collection_id": "cvfqr-6b645",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141118-102135823",
"type": "article",
"title": "Silylation of C\u2013H bonds in aromatic heterocycles by an Earth-abundant metal catalyst",
"author": [
{
"family_name": "Toutov",
"given_name": "Anton A.",
"orcid": "0000-0002-6561-0462",
"clpid": "Toutov-A-A"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Betz",
"given_name": "Kerry N.",
"orcid": "0000-0001-9118-5909",
"clpid": "Betz-K-N"
},
{
"family_name": "Fedorov",
"given_name": "Alexey",
"orcid": "0000-0001-9814-6726",
"clpid": "Fedorov-Alexey"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
}
],
"abstract": "Heteroaromatic compounds containing carbon\u2013silicon (C\u2013Si) bonds are of great interest in the fields of organic electronics and photonics1, drug discovery, nuclear medicine and complex molecule synthesis, because these compounds have very useful physicochemical properties. Many of the methods now used to construct heteroaromatic C\u2013Si bonds involve stoichiometric reactions between heteroaryl organometallic species and silicon electrophiles or direct, transition-metal-catalysed intermolecular carbon\u2013hydrogen (C\u2013H) silylation using rhodium or iridium complexes in the presence of excess hydrogen acceptors. Both approaches are useful, but their limitations include functional group incompatibility, narrow scope of application, high cost and low availability of the catalysts, and unproven scalability. For this reason, a new and general catalytic approach to heteroaromatic C\u2013Si bond construction that avoids such limitations is highly desirable. Here we report an example of cross-dehydrogenative heteroaromatic C\u2013H functionalization catalysed by an Earth-abundant alkali metal species. We found that readily available and inexpensive potassium tert-butoxide catalyses the direct silylation of aromatic heterocycles with hydrosilanes, furnishing heteroarylsilanes in a single step. The silylation proceeds under mild conditions, in the absence of hydrogen acceptors, ligands or additives, and is scalable to greater than 100 grams under optionally solvent-free conditions. Substrate classes that are difficult to activate with precious metal catalysts are silylated in good yield and with excellent regioselectivity. The derived heteroarylsilane products readily engage in versatile transformations enabling new synthetic strategies for heteroaromatic elaboration, and are useful in their own right in pharmaceutical and materials science applications.",
"doi": "10.1038/nature14126",
"issn": "0028-0836",
"publisher": "Nature Publishing Group",
"publication": "Nature",
"publication_date": "2015-02-05",
"series_number": "7537",
"volume": "518",
"issue": "7537",
"pages": "80-84"
},
{
"id": "authors:pspja-z9w02",
"collection": "authors",
"collection_id": "pspja-z9w02",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150126-101327424",
"type": "article",
"title": "Enantioselective Synthesis of \u03b1\u2011Quaternary Mannich Adducts by Palladium-Catalyzed Allylic Alkylation: Total Synthesis of (+)-Sibirinine",
"author": [
{
"family_name": "Numajiri",
"given_name": "Yoshitaka",
"clpid": "Numajiri-Yoshitaka"
},
{
"family_name": "Pritchett",
"given_name": "Beau P.",
"orcid": "0000-0001-9922-9160",
"clpid": "Pritchett-B-P"
},
{
"family_name": "Chiyoda",
"given_name": "Koji",
"clpid": "Chiyoda-Koji"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic enantioselective method for the synthesis of \u03b1-quaternary Mannich-type products is reported. The two-step sequence of (1) Mannich reaction followed by (2) decarboxylative enantioselective allylic alkylation serves as a novel strategy to in effect access asymmetric Mannich-type products of \"thermodynamic\" enolates of substrates possessing additional enolizable positions and acidic protons. Palladium-catalyzed decarboxylative allylic alkylation enables the enantioselective synthesis of five-, six-, and seven-membered ketone, lactam, and other heterocyclic systems. The mild reaction conditions are notable given the acidic free N\u2013H groups and high functional group tolerance in each of the substrates. The utility of this method is highlighted in the first total synthesis of (+)-sibirinine.",
"doi": "10.1021/ja512124c",
"pmcid": "PMC4311947",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2015-01-28",
"series_number": "3",
"volume": "137",
"issue": "3",
"pages": "1040-1043"
},
{
"id": "authors:xd0c2-mre88",
"collection": "authors",
"collection_id": "xd0c2-mre88",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141117-092808886",
"type": "article",
"title": "Enantioselective Synthesis of \u03b1-Secondary and \u03b1-Tertiary Piperazin-2-ones and Piperazines by Catalytic Asymmetric Allylic Alkylation",
"author": [
{
"family_name": "Korch",
"given_name": "Katerina M.",
"clpid": "Korch-K-M"
},
{
"family_name": "Eidamshaus",
"given_name": "Christian",
"clpid": "Eidamshaus-C"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Nam",
"given_name": "Sangkil",
"clpid": "Nam-Sangkil"
},
{
"family_name": "Horne",
"given_name": "David",
"clpid": "Horne-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The asymmetric palladium-catalyzed decarboxylative allylic alkylation of differentially N-protected piperazin-2-ones allows the synthesis of a variety of highly enantioenriched tertiary piperazine-2-ones. Deprotection and reduction affords the corresponding tertiary piperazines, which can be employed for the synthesis of medicinally important analogues. The introduction of these chiral tertiary piperazines resulted in imatinib analogues which exhibited comparable antiproliferative activity to that of their corresponding imatinib counterparts.",
"doi": "10.1002/anie.201408609",
"pmcid": "PMC4285707",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2015-01-02",
"series_number": "1",
"volume": "54",
"issue": "1",
"pages": "179-183"
},
{
"id": "authors:yrcev-z9c82",
"collection": "authors",
"collection_id": "yrcev-z9c82",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141202-144818205",
"type": "article",
"title": "Evolution of a Unified, Stereodivergent Approach to the Synthesis of Communesin F and Perophoramidine",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Vogt",
"given_name": "Florian",
"clpid": "Vogt-Florian"
},
{
"family_name": "May",
"given_name": "Jeremy A.",
"clpid": "May-J-A"
},
{
"family_name": "Krishnan",
"given_name": "Shyam",
"clpid": "Krishnan-Shyam"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Expedient synthetic approaches to the highly functionalized polycyclic alkaloids communesin F and perophoramidine are described using a unified approach featuring a key decarboxylative allylic alkylation to access a crucial and highly congested 3,3-disubstituted oxindole. Described are two distinct, stereoselective alkylations that produce structures in divergent diastereomeric series possessing the critical vicinal all-carbon quaternary centers needed for each synthesis. Synthetic studies toward these challenging core structures have revealed a number of unanticipated modes of reactivity inherent to these complex alkaloid scaffolds. Additionally, several novel and interesting intermediates en route to the target natural products, such as an intriguing propellane hexacyclic oxindole encountered in the communesin F sequence, are disclosed. Indeed, such unanticipated structures may prove to be convenient strategic intermediates in future syntheses.",
"doi": "10.1021/jo502534g",
"pmcid": "PMC4285143",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2015-01-02",
"series_number": "1",
"volume": "80",
"issue": "1",
"pages": "528-547"
},
{
"id": "authors:3gdvm-dth64",
"collection": "authors",
"collection_id": "3gdvm-dth64",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141215-090404543",
"type": "article",
"title": "A Catalytic, Enantioselective Formal Synthesis of (+)-Dichroanone and (+)-Taiwaniaquinone H",
"author": [
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"clpid": "Shockley-S-E"
},
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic, enantioselective formal synthesis of (+)-dichroanone and (+)-taiwaniaquinone H is reported. The all-carbon quaternary stereocenter was constructed by asymmetric conjugate addition catalyzed by a palladium(II) (S)-tert-butylpyridinooxazoline complex. The unexpected formation of a [3.2.1] bicyclic intermediate required the identification of a new route. Analysis of the Hammett constants for para-substituted arenes enabled the rational design of a highly enantioselective conjugate addition substrate that led to the completion of the formal synthesis.",
"doi": "10.1021/ol5031537",
"pmcid": "PMC4275150",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2014-12-19",
"series_number": "24",
"volume": "16",
"issue": "24",
"pages": "6362-6365"
},
{
"id": "authors:d6cpr-tgy14",
"collection": "authors",
"collection_id": "d6cpr-tgy14",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141020-152334369",
"type": "article",
"title": "A new method for the cleavage of nitrobenzyl amides and ethers",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-S-J"
},
{
"family_name": "de Melo",
"given_name": "Gabriel Fernando",
"clpid": "de-Melo-G-F"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A mild and efficient o- and p-nitrobenzyl cleavage protocol was developed. o- and p-nitrobenzyl groups were easily removed from a variety of substrates using 20% aqueous NaOH in methanol at 75 \u00b0C, presumably via oxidation at the benzylic position by oxygen dissolved in the solution. These easily introducible and removable nitrobenzyl groups can serve as valuable protecting groups for the synthesis of multifunctional, complex molecules.",
"doi": "10.1016/j.tetlet.2014.10.006",
"pmcid": "PMC4228375",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2014-11-19",
"series_number": "47",
"volume": "55",
"issue": "47",
"pages": "6467-6469"
},
{
"id": "authors:z71n8-58656",
"collection": "authors",
"collection_id": "z71n8-58656",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141215-084337170",
"type": "article",
"title": "Formal total syntheses of classic natural product target molecules via palladium-catalyzed enantioselective alkylation",
"author": [
{
"family_name": "Liu",
"given_name": "Yiyang",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Liniger",
"given_name": "Marc",
"clpid": "Liniger-M"
},
{
"family_name": "McFadden",
"given_name": "Ryan M.",
"clpid": "McFadden-R-M"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-J-L"
},
{
"family_name": "Malette",
"given_name": "Jacquie",
"clpid": "Malette-J"
},
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-C-M"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Seto",
"given_name": "Masaki",
"clpid": "Seto-Masaki"
},
{
"family_name": "Kim",
"given_name": "Jimin",
"clpid": "Kim-Jimin"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Pd-catalyzed enantioselective alkylation in conjunction with further synthetic elaboration enables the formal total syntheses of a number of \"classic\" natural product target molecules. This publication highlights recent methods for setting quaternary and tetrasubstituted tertiary carbon stereocenters to address the synthetic hurdles encountered over many decades across multiple compound classes spanning carbohydrate derivatives, terpenes, and alkaloids. These enantioselective methods will impact both academic and industrial settings, where the synthesis of stereogenic quaternary carbons is a continuing challenge.",
"doi": "10.3762/bjoc.10.261",
"pmcid": "PMC4222294",
"issn": "1860-5397",
"publisher": "Beilstein-Institut",
"publication": "Beilstein Journal of Organic Chemistry",
"publication_date": "2014-10-28",
"volume": "10",
"pages": "2501-2512"
},
{
"id": "authors:qg5vg-pm017",
"collection": "authors",
"collection_id": "qg5vg-pm017",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141015-093052860",
"type": "article",
"title": "The Total Syntheses of Basiliolide C, epi-Basiliolide C, and Protecting-Group-Free Total Syntheses of Transtaganolides C and D",
"author": [
{
"family_name": "Gordon",
"given_name": "Jonny R.",
"clpid": "Gordon-J-R"
},
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The total syntheses of basiliolide C and previously unreported epi-basiliolide C are achieved by an Ireland\u2013Claisen/Diels\u2013Alder cascade. The development of a palladium catalyzed cross-coupling of methoxy alkynyl zinc reagents allows for the protecting-group-free syntheses of transtaganolides C and D. Syntheses of transtaganolides C and D are accomplished in a single operation to generate three rings, two all-carbon quaternary centers, and four tertiary stereocenters from a monocyclic, achiral precursor.",
"doi": "10.1021/jo501924u",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2014-10-17",
"series_number": "20",
"volume": "79",
"issue": "20",
"pages": "9740-9747"
},
{
"id": "authors:40907-smv43",
"collection": "authors",
"collection_id": "40907-smv43",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-150326033",
"type": "conference_item",
"title": "Development and application of a palladium-catalyzed enantioselective conjugate addition",
"author": [
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Shockley",
"given_name": "Samantha E.",
"clpid": "Shockley-S-E"
},
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-A-N"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Kikushima",
"given_name": "Kotaro",
"clpid": "Kikushima-Kotaro"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective palladium-catalyzed, asym. construction of all-carbon quaternary stereocenters via 1, 4-addn. of arylboronic acids to cyclic, \u03b2-substituted enones is reported. A wide range of arylboronic acids and cyclic enones are reacted utilizing a catalyst prepd. from palladium(II) trifluoroacetate and a chiral pyridinooxazoline ligand to yield enantioenriched products bearing benzylic stereocenters. Recently, this methodol. has been expanded to support the reaction of heterocyclic chromone and 4-quinolone conjugate acceptors. Notably, this transformation is insensitive to air or moisture, providing a practical and operationally simple method of synthesizing enantioenriched stereocenters. The application of this reaction toward the total syntheses of members of the taiwaniaquinone sesquiterpenoid family of natural products is discussed.",
"publisher": "Caltech Library",
"publication_date": "2014-08"
},
{
"id": "authors:mmn8r-cp850",
"collection": "authors",
"collection_id": "mmn8r-cp850",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-150157474",
"type": "conference_item",
"title": "Asymmetric synthesis of QUINAP via dynamic kinetic resolution",
"author": [
{
"family_name": "Bhat",
"given_name": "Vikram",
"orcid": "0000-0001-5621-5121",
"clpid": "Bhat-V"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A Pd-catalyzed, atroposelective C-P coupling process has been developed for the asym. synthesis of QUINAP and its derivs. in high enantiomeric excess. Bromide, triflate (OTf) and 4-methanesulfonylbenzenesulfonate (OSs) precursors were studied, leading in the case of the triflate to a novel dynamic kinetic resoln. involving isomerization of an arylpalladium intermediate. The operationally simple methods described in this communication afford these important ligands in good to high yields and selectivity using low catalyst loading (\u22643 mol % Pd).",
"publisher": "Caltech Library",
"publication_date": "2014-08"
},
{
"id": "authors:vyzyh-rf045",
"collection": "authors",
"collection_id": "vyzyh-rf045",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140421-084129624",
"type": "article",
"title": "Palladium-catalyzed decarboxylative allylic alkylation of diastereomeric \u03b2-ketoesters",
"author": [
{
"family_name": "Ma",
"given_name": "Sandy",
"clpid": "Ma-Sandy"
},
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-C-M"
},
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-R-A-II"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The palladium-catalyzed decarboxylative allylic alkylation of diastereomeric \u03b2-ketoesters derived from 4-tert-butylcyclohexanone is described. These experiments were performed to elucidate our understanding of stereoablative enantioconvergent catalysis. A detailed analysis of the product distribution, including stereochemical outcome of the products, is included. These studies also reveal an interesting example of selectivity that is governed by competing modes of substrate and catalyst control.",
"doi": "10.1016/j.tet.2014.03.042",
"pmcid": "PMC4078409",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2014-07-08",
"series_number": "27-28",
"volume": "70",
"issue": "27-28",
"pages": "4208-4212"
},
{
"id": "authors:01vn3-r6040",
"collection": "authors",
"collection_id": "01vn3-r6040",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140616-094313057",
"type": "article",
"title": "A Diastereodivergent Synthetic Strategy for the Syntheses of Communesin F and Perophoramidine",
"author": [
{
"family_name": "Han",
"given_name": "Seo-Jung",
"clpid": "Han-Seo-Jung"
},
{
"family_name": "Vogt",
"given_name": "Florian",
"clpid": "Vogt-F"
},
{
"family_name": "Krishnan",
"given_name": "Shyam",
"clpid": "Krishnan-Shyam"
},
{
"family_name": "May",
"given_name": "Jeremy A.",
"clpid": "May-J-A"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An efficient, unified, and stereodivergent approach toward communesin F and perophoramidine was examined. The C(3) all-carbon quaternary center of an oxindole was smoothly constructed by base-promoted indolone-malonate alkylation chemistry. The complementary relative stereochemistry of the crucial vicinal quaternary centers found in communesin F and perophoramidine was selectively installed by substrate-controlled decarboxylative allylic alkylations.",
"doi": "10.1021/ol5013263",
"pmcid": "PMC4068777",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2014-06-20",
"series_number": "12",
"volume": "16",
"issue": "12",
"pages": "3316-3319"
},
{
"id": "authors:962qn-jw749",
"collection": "authors",
"collection_id": "962qn-jw749",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140505-091759313",
"type": "article",
"title": "Biosynthesis and Chemical Synthesis of Presilphiperfolanol Natural Products",
"author": [
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Presilphiperfolanols constitute a family of biosynthetically important sesquiterpenes which can rearrange to diverse sesquiterpenoid skeletons. While the origin of these natural products can be traced to simple linear terpene precursors, the details of the enzymatic cyclization mechanism that forms the stereochemically dense tricyclic skeleton has required extensive biochemical, computational, and synthetic investigation. Parallel efforts to prepare the unique and intriguing structures of these compounds by total synthesis have also inspired novel strategies, thus resulting in four synthetic approaches and two completed syntheses. While the biosynthesis and chemical synthesis studies performed to date have provided much insight into the role and properties of these molecules, emerging questions regarding the biosynthesis of newer members of the family and subtle details of rearrangement mechanisms have yet to be explored.",
"doi": "10.1002/anie.201309494",
"pmcid": "PMC4334158",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2014-05-19",
"series_number": "21",
"volume": "53",
"issue": "21",
"pages": "5248-5260"
},
{
"id": "authors:k5k7r-xdq58",
"collection": "authors",
"collection_id": "k5k7r-xdq58",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140424-145313873",
"type": "article",
"title": "Development of (Trimethylsilyl)ethyl Ester Protected Enolates and Applications in Palladium-Catalyzed Enantioselective Allylic Alkylation: Intermolecular Cross-Coupling of Functionalized Electrophiles",
"author": [
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-C-M"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The development of (trimethylsilyl)ethyl ester protected enolates is reported. The application of this class of compounds in palladium-catalyzed asymmetric allylic alkylation is explored, yielding a variety of \u03b1-quaternary six- and seven-membered ketones and lactams. Independent coupling partner synthesis engenders enhanced allyl substrate scope relative to traditional \u03b2-ketoester substrates; highly functionalized \u03b1-quaternary ketones generated by the union of (trimethylsilyl)ethyl \u03b2-ketoesters and sensitive allylic alkylation coupling partners serve to demonstrate the utility of this method for complex fragment coupling.",
"doi": "10.1021/ol500355z",
"pmcid": "PMC4011571",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2014-05-02",
"series_number": "9",
"volume": "16",
"issue": "9",
"pages": "2314-2317"
},
{
"id": "authors:gd2tk-q1r89",
"collection": "authors",
"collection_id": "gd2tk-q1r89",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140310-100420677",
"type": "article",
"title": "Stereoselective Lewis Acid Mediated (3+2) Cycloadditions of N-H- and N-Sulfonylaziridines with Heterocumulenes",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-R-A-II"
},
{
"family_name": "O'Connor",
"given_name": "Nicholas R.",
"clpid": "O'Connor-N-R"
},
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Alkyl and aryl isothiocyanates and carbodiimides are effective substrates in (3+2) cycloadditions with N-sulfonyl-2-substituted aziridines and 2-phenylaziridine for the synthesis of iminothiazolidines and iminoimidazolidines. Additionally, the stereoselective (3+2) cycloaddition of N-H- and N-sulfonylaziridines with isothiocyanates can be accomplished, allowing for the synthesis of highly enantioenriched iminothiazolidines. Evidence for an intimate ion-pair mechanism is presented herein in the context of these chemo-, regio-, and diastereoselective transformations. The demonstrated ability to remove the sulfonyl group from the heterocyclic products displays the utility of these compounds for further derivatization and application.",
"doi": "10.1002/chem.201303699",
"pmcid": "PMC4104980",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2014-04-14",
"series_number": "16",
"volume": "20",
"issue": "16",
"pages": "4806-4813"
},
{
"id": "authors:hv63r-awc61",
"collection": "authors",
"collection_id": "hv63r-awc61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140501-092433445",
"type": "article",
"title": "Toward a Symphony of Reactivity: Cascades Involving Catalysis and Sigmatropic Rearrangements",
"author": [
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-A-C"
},
{
"family_name": "May",
"given_name": "Jeremy A.",
"clpid": "May-J-A"
},
{
"family_name": "Sarpong",
"given_name": "Richmond",
"orcid": "0000-0002-0028-6323",
"clpid": "Sarpong-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Catalysis and synthesis are intimately linked in modern organic chemistry. The synthesis of complex molecules is an ever evolving area of science. In many regards, the inherent beauty associated with a synthetic sequence can be linked to a certain combination of the creativity with which a sequence is designed and the overall efficiency with which the ultimate process is performed. In synthesis, as in other endeavors, beauty is very much in the eyes of the beholder.\u2020 It is with this in mind that we will attempt to review an area of synthesis that has fascinated us and that we find extraordinarily beautiful, namely the combination of catalysis and sigmatropic rearrangements in consecutive and cascade sequences.",
"doi": "10.1002/anie.201302572",
"pmcid": "PMC4030764",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2014-03-03",
"series_number": "10",
"volume": "53",
"issue": "10",
"pages": "2556-2591"
},
{
"id": "authors:4qs8k-tjn63",
"collection": "authors",
"collection_id": "4qs8k-tjn63",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140210-145231305",
"type": "article",
"title": "Gas Phase Production and Loss of Isoprene Epoxydiols",
"author": [
{
"family_name": "Bates",
"given_name": "Kelvin H.",
"orcid": "0000-0001-7544-9580",
"clpid": "Bates-K-H"
},
{
"family_name": "Crounse",
"given_name": "John D.",
"orcid": "0000-0001-5443-729X",
"clpid": "Crounse-J-D"
},
{
"family_name": "St. Clair",
"given_name": "Jason M.",
"orcid": "0000-0002-9367-5749",
"clpid": "St-Clair-J-M"
},
{
"family_name": "Bennett",
"given_name": "Nathan B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Nguyen",
"given_name": "Tran B.",
"clpid": "Nguyen-Tran-B"
},
{
"family_name": "Seinfeld",
"given_name": "John H.",
"orcid": "0000-0003-1344-4068",
"clpid": "Seinfeld-J-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Wennberg",
"given_name": "Paul O.",
"orcid": "0000-0002-6126-3854",
"clpid": "Wennberg-P-O"
}
],
"abstract": "Isoprene epoxydiols (IEPOX) form in high yields from the OH-initiated oxidation of isoprene under low-NO conditions. These compounds contribute significantly to secondary organic aerosol formation. Their gas-phase chemistry has, however, remained largely unexplored. In this study, we characterize the formation of IEPOX isomers from the oxidation of isoprene by OH. We find that cis-\u03b2- and trans-\u03b2-IEPOX are the dominant isomers produced, and that they are created in an approximate ratio of 1:2 from the low-NO oxidation of isoprene. Three isomers of IEPOX, including cis-\u03b2- and trans-\u03b2, were synthesized and oxidized by OH in environmental chambers under high- and low-NO conditions. We find that IEPOX reacts with OH at 299 K with rate coefficients of (0.84 \u00b1 0.07) \u00d7 10^(\u201311), (1.52 \u00b1 0.07) \u00d7 10^(\u201311), and (0.98 \u00b1 0.05) \u00d7 10^(\u201311) cm^3 molecule^(\u20131) s^(\u20131) for the \u03b41, cis-\u03b2, and trans-\u03b2 isomers. Finally, yields of the first-generation products of IEPOX + OH oxidation were measured, and a new mechanism of IEPOX oxidation is proposed here to account for the observed products. The substantial yield of glyoxal and methylglyoxal from IEPOX oxidation may help explain elevated levels of those compounds observed in low-NO environments with high isoprene emissions.",
"doi": "10.1021/jp4107958",
"issn": "1089-5639",
"publisher": "American Chemical Society",
"publication": "Journal of Physical Chemistry A",
"publication_date": "2014-02-20",
"series_number": "7",
"volume": "118",
"issue": "7",
"pages": "1237-1246"
},
{
"id": "authors:xxdex-e6m67",
"collection": "authors",
"collection_id": "xxdex-e6m67",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140214-093051277",
"type": "article",
"title": "Angiotensin II Receptor Type 1\u2014A Novel Target for Preventing Neonatal Meningitis in Mice by Escherichia coli K1",
"author": [
{
"family_name": "Krishnan",
"given_name": "Subramanian",
"orcid": "0000-0001-5780-7452",
"clpid": "Krishnan-Subramanian"
},
{
"family_name": "Shanmuganathan",
"given_name": "Muthusamy V.",
"clpid": "Shanmuganathan-Muthusamy-V"
},
{
"family_name": "Behenna",
"given_name": "Douglas",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Prasadarao",
"given_name": "Nemani V.",
"clpid": "Prasadarao-N-V"
}
],
"abstract": "The increasing incidence of Escherichia coli K1 meningitis due to escalating antibiotic resistance warrants alternate treatment options to prevent this deadly disease. We screened a library of small molecules from the National Institutes of Health clinical collection and identified telmisartan, an angiotensin II receptor type 1 (AT1R) blocker, as a potent inhibitor of E. coli invasion into human brain microvascular endothelial cells (HBMECs). Immunoprecipitation studies revealed that AT1R associates with endothelial cell gp96, the receptor in HBMECs for E. coli outer membrane protein A. HBMECs pretreated with telmisartan or transfected with AT1R small interfering RNA were resistant to E. coli invasion because of downregulation of protein kinase C-\u03b1 phosphorylation. Administration of a soluble derivative of telmisartan to newborn mice before infection with E. coli prevented the onset of meningitis and suppressed neutrophil infiltration and glial cell migration in the brain. Therefore, telmisartan has potential as an alternate treatment option for preventing E. coli meningitis.",
"doi": "10.1093/infdis/jit499",
"pmcid": "PMC3883175",
"issn": "0022-1899",
"publisher": "Oxford University Press",
"publication": "Journal of Infectious Diseases",
"publication_date": "2014-02-01",
"series_number": "3",
"volume": "209",
"issue": "3",
"pages": "409-419"
},
{
"id": "authors:q5j5w-8vs63",
"collection": "authors",
"collection_id": "q5j5w-8vs63",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140122-135551444",
"type": "article",
"title": "Palladium-Catalyzed Decarbonylative Dehydration of Fatty Acids for the Production of Linear Alpha Olefins",
"author": [
{
"family_name": "Liu",
"given_name": "Yiyang",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Kim",
"given_name": "Kelly E.",
"clpid": "Kim-Kelly-E"
},
{
"family_name": "Herbert",
"given_name": "Myles B.",
"clpid": "Herbert-M-B"
},
{
"family_name": "Fedorov",
"given_name": "Alexey",
"orcid": "0000-0001-9814-6726",
"clpid": "Fedorov-Alexey"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A highly efficient palladium-catalyzed decarbonylative dehydration reaction of carboxylic acids is reported. This method transforms abundant and renewable even-numbered natural fatty acids into valuable and expensive odd-numbered alpha olefins. Additionally, the chemistry displays a high functional group tolerance. The process employs a low loading of palladium catalyst and proceeds under solvent-free and relatively mild conditions.",
"pmcid": "PMC3998208",
"issn": "1615-4150",
"publisher": "Wiley",
"publication": "Advanced Synthesis and Catalysis",
"publication_date": "2014-01-13",
"series_number": "1",
"volume": "356",
"issue": "1",
"pages": "130-136"
},
{
"id": "authors:cdjse-pc337",
"collection": "authors",
"collection_id": "cdjse-pc337",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150126-091231023",
"type": "book_section",
"title": "Alkylations of Enols and Enolates",
"book_title": "Comprehensive Organic Synthesis II",
"author": [
{
"family_name": "Stoltz",
"given_name": "B. M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Bennett",
"given_name": "N. B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Duquette",
"given_name": "D. C.",
"clpid": "Duquette-D-C"
},
{
"family_name": "Goldberg",
"given_name": "A. F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "Liu",
"given_name": "Y.",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Loewinger",
"given_name": "M. B.",
"clpid": "Loewinger-M-B"
},
{
"family_name": "Reeves",
"given_name": "C. M.",
"clpid": "Reeves-C-M"
}
],
"contributor": [
{
"family_name": "Knochel",
"given_name": "Paul",
"clpid": "Knochel-P"
},
{
"family_name": "Molander",
"given_name": "Gary A.",
"clpid": "Molander-G-A"
}
],
"abstract": "Enolate alkylation, the nucleophilic substitution of electrophilic alkylating reagents by carbon nucleophiles generated from the adeprotonation\nof carbonyl compounds, is one among the most fundamental and important methods for the construction of\ncarbon\u2013carbon bonds adjacent to a carbonyl group. Over the past fifty years, this methodology has evolved into a highly selective,\nefficient, and essential technique integral to the practitioners of pharmaceutical industry, chemical biology, and academic organic\nsynthesis.\nSince the previous publication of Comprehensive Organic Synthesis in 1991, a field-wide explosion of interest in catalysis has\nsparked the development of numerous metal and metal-free catalytic alkylation methods. These advances have introduced new\nmethods for enolate formation, expanded substrate scope, and enabled highly stereoselective \u03b1-alkylations. New techniques allow\nelaboration of a diverse array of small molecules and have made enolate alkylation one of the most important methods for\nasymmetric carbon\u2013carbon bond formation.\nOwing to the overwhelming wealth of literature on carbonyl chemistry, attempt has been made to narrowly define 'enolate\nalkylation' to encompass only the reactions of enolates with sp^3-hybridized carbon electrophiles. Aldol reactions, conjugate\nadditions, arylations, and functionalizations of enamines and metalloenamines will be addressed in other chapters of this\ncompendium.",
"doi": "10.1016/B978-0-08-097742-3.00301-3",
"isbn": "978-0-08-097743-0",
"publisher": "Elsevier",
"place_of_publication": "Amsterdam",
"publication_date": "2014",
"pages": "1-55"
},
{
"id": "authors:m5g4s-aps61",
"collection": "authors",
"collection_id": "m5g4s-aps61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131209-101849386",
"type": "article",
"title": "A Unified Approach to the Daucane and Sphenolobane Bicyclo[5.3.0]decane Core: Enantioselective Total Syntheses of Daucene, Daucenal, Epoxydaucenal\u2005B, and 14-para-Anisoyloxydauc-4,8-diene",
"author": [
{
"family_name": "Bennett",
"given_name": "Nathan B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Access to the bicyclo[5.3.0]decane core found in the daucane and sphenolobane terpenoids via a key enone intermediate enables the enantioselective total syntheses of daucene, daucenal, epoxydaucenal\u2005B, and 14-para-anisoyloxydauc-4,8-diene. Central aspects include a catalytic asymmetric alkylation followed by a ring contraction and ring-closing metathesis to generate the five- and seven-membered rings, respectively.",
"doi": "10.1002/chem.201302353",
"pmcid": "PMC3927641",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2013-12-23",
"series_number": "52",
"volume": "19",
"issue": "52",
"pages": "17745-17750"
},
{
"id": "authors:e7w22-24p12",
"collection": "authors",
"collection_id": "e7w22-24p12",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140106-104251997",
"type": "article",
"title": "Enantio-, Diastereo-, and Regioselective Iridium-Catalyzed Asymmetric Allylic Alkylation of Acyclic \u03b2-Ketoesters",
"author": [
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-C-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first regio-, diastereo-, and enantioselective allylic alkylation of acyclic \u03b2-ketoesters to form vicinal tertiary and all-carbon quaternary stereocenters is reported. Critical to the successful development of this method was the employment of iridium catalysis in concert with N-aryl-phosphoramidite ligands. Broad functional group tolerance is observed at the keto-, ester-, and \u03b1-positions of the nucleophile. Various transformations demonstrating the utility of this method for rapidly accessing complex enantioenriched compounds are reported.",
"doi": "10.1021/ja4097829",
"pmcid": "PMC3881553",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2013-11-20",
"series_number": "46",
"volume": "135",
"issue": "46",
"pages": "17298-17301"
},
{
"id": "authors:4mfcq-a8k25",
"collection": "authors",
"collection_id": "4mfcq-a8k25",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131108-073355250",
"type": "article",
"title": "Asymmetric Synthesis of QUINAP via Dynamic Kinetic Resolution",
"author": [
{
"family_name": "Bhat",
"given_name": "Vikram",
"orcid": "0000-0001-5621-5121",
"clpid": "Bhat-V"
},
{
"family_name": "Wang",
"given_name": "Su",
"clpid": "Wang-Su"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
}
],
"abstract": "A palladium-catalyzed, atroposelective C\u2212P coupling process has been developed for the asymmetric synthesis of QUINAP and its derivatives in high enantiomeric excess. Bromide, triflate (OTf) and 4-methanesulfonylbenzenesulfonate (OSs) precursors were studied, leading in the case of the triflate to a novel\ndynamic kinetic resolution involving isomerization of an arylpalladium intermediate. The operationally simple\nmethods described in this communication afford these important ligands in good to high yields and selectivity\nusing low catalyst loading (\u22643 mol % Pd).",
"doi": "10.1021/ja409383f",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2013-11-13",
"series_number": "45",
"volume": "135",
"issue": "45",
"pages": "16829-16832"
},
{
"id": "authors:sby8t-8bn23",
"collection": "authors",
"collection_id": "sby8t-8bn23",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131105-114622242",
"type": "article",
"title": "Mechanism and Enantioselectivity in Palladium-Catalyzed Conjugate Addition of Arylboronic Acids to \u03b2\u2011Substituted Cyclic Enones: Insights from Computation and Experiment",
"author": [
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Zou",
"given_name": "Lufeng",
"clpid": "Zou-Lufeng"
},
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-A-N"
},
{
"family_name": "Liu",
"given_name": "Peng",
"orcid": "0000-0002-8188-632X",
"clpid": "Liu-Peng-Chemistry"
},
{
"family_name": "Lan",
"given_name": "Yu",
"clpid": "Lan-Yu"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Kikushima",
"given_name": "Kotaro",
"clpid": "Kikushima-Kotaro"
},
{
"family_name": "Houk",
"given_name": "K. N.",
"orcid": "0000-0002-8387-5261",
"clpid": "Houk-K-N"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Enantioselective conjugate additions of arylboronic acids to \u03b2-substituted cyclic enones have been previously reported from our laboratories. Air- and moisture-tolerant conditions were achieved with a catalyst derived in situ from palladium(II) trifluoroacetate and the chiral ligand (S)-t-BuPyOx. We now report a combined experimental and computational investigation on the mechanism, the nature of the active catalyst, the origins of the enantioselectivity, and the stereoelectronic effects of the ligand and the substrates of this transformation. Enantioselectivity is controlled primarily by steric repulsions between the t-Bu group of the chiral ligand and the \u03b1-methylene hydrogens of the enone substrate in the enantiodetermining carbopalladation step. Computations indicate that the reaction occurs via formation of a cationic arylpalladium(II) species, and subsequent carbopalladation of the enone olefin forms the key carbon\u2013carbon bond. Studies of nonlinear effects and stoichiometric and catalytic reactions of isolated (PyOx)Pd(Ph)I complexes show that a monomeric arylpalladium\u2013ligand complex is the active species in the selectivity-determining step. The addition of water and ammonium hexafluorophosphate synergistically increases the rate of the reaction, corroborating the hypothesis that a cationic palladium species is involved in the reaction pathway. These additives also allow the reaction to be performed at 40 \u00b0C and facilitate an expanded substrate scope.",
"doi": "10.1021/ja401713g",
"pmcid": "PMC3846424",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2013-10-09",
"series_number": "40",
"volume": "135",
"issue": "40",
"pages": "14996-15007"
},
{
"id": "authors:acj7r-2x223",
"collection": "authors",
"collection_id": "acj7r-2x223",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131003-103642590",
"type": "article",
"title": "Use of a palladium(II)-catalyzed oxidative kinetic resolution in synthetic efforts toward bielschowskysin",
"author": [
{
"family_name": "Meyer",
"given_name": "Michael E.",
"clpid": "Meyer-M-E"
},
{
"family_name": "Phillips",
"given_name": "John H.",
"clpid": "Phillips-J-H"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Progress toward the cyclobutane core of bielshowskysin is reported. The core was thought to arise from a cyclopropane intermediate via a furan-mediated cyclopropane fragmentation, followed by a 1,4-Michael addition. The synthesis of the cyclopropane intermediate utilizes a Suzuki coupling reaction, an esterification with 2-diazoacetoacetic acid, and a copper catalyzed cyclopropanation. An alcohol intermediate within the synthetic route was obtained in high enantiopurity via a highly selective palladium(II)-catalyzed oxidative kinetic resolution (OKR).",
"doi": "10.1016/j.tet.2013.02.034",
"pmcid": "PMC3728638",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2013-09-09",
"series_number": "36",
"volume": "69",
"issue": "36",
"pages": "7627-7635"
},
{
"id": "authors:me85x-yva10",
"collection": "authors",
"collection_id": "me85x-yva10",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130906-155635457",
"type": "article",
"title": "A scalable synthesis of the (S)-4-(tert-butyl)-2-(pyridin-2-yl)-4,5-dihydrooxazole ((S)-t-BuPyOx) ligand",
"author": [
{
"family_name": "Shimizu",
"given_name": "Hideki",
"clpid": "Shimizu-Hideki"
},
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An efficient method for the synthesis of the (S)-4-(tert-butyl)-2-(pyridin-2-yl)-4,5-dihydrooxazole ((S)-t-BuPyOx) ligand has been\ndeveloped. Inconsistent yields and tedious purification in known routes to (S)-t-BuPyOx suggested the need for an efficient,\ndependable, and scalable synthetic route. Furthermore, a route suitable for the synthesis of PyOx derivatives is desirable. Herein,\nwe describe the development of a three-step route from inexpensive and commercially available picolinic acid. This short procedure\nis amenable to multi-gram scale synthesis and provides the target ligand in 64% overall yield.",
"doi": "10.3762/bjoc.9.187",
"pmcid": "PMC3778391",
"issn": "1860-5397",
"publisher": "Beilstein-Institut",
"publication": "Beilstein Journal of Organic Chemistry",
"publication_date": "2013-08-12",
"volume": "9",
"pages": "1637-1642"
},
{
"id": "authors:rx9yn-ys137",
"collection": "authors",
"collection_id": "rx9yn-ys137",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131002-102340513",
"type": "article",
"title": "Construction of Vicinal Tertiary and All-Carbon Quaternary Stereocenters via Ir-Catalyzed Regio-, Diastereo-, and Enantioselective Allylic Alkylation and Applications in Sequential Pd Catalysis",
"author": [
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-C-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Highly congested vicinal stereocenters comprised of tertiary and all-carbon quaternary centers were generated via Ir-catalyzed asymmetric allylic alkylation of \u03b2-ketoesters. These catalytic reactions proceed in excellent yields with a broad scope on either reaction partner and with outstanding regio-, diastereo-, and enantiocontrol. Implementation of a subsequent Pd-catalyzed alkylation affords dialkylated products with pinpoint stereochemical control of both chiral centers.",
"doi": "10.1021/ja4052075",
"pmcid": "PMC3756902",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2013-07-24",
"series_number": "29",
"volume": "135",
"issue": "29",
"pages": "10626-10629"
},
{
"id": "authors:418qc-2sp48",
"collection": "authors",
"collection_id": "418qc-2sp48",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130802-141019170",
"type": "article",
"title": "Development of a palladium-catalyzed decarboxylative cross-coupling of (2-azaaryl)carboxylates with aryl halides",
"author": [
{
"family_name": "Haley",
"given_name": "Christopher K.",
"clpid": "Haley-C-K"
},
{
"family_name": "Gilmore",
"given_name": "Christopher D.",
"clpid": "Gilmore-C-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic method for the decarboxylative coupling of 2-(azaaryl)carboxylates with aryl halides is described. The decarboxylative cross-coupling presented is mediated by a system catalytic in both palladium and copper without requiring stoichiometric amounts of organometallic reagents or organoboronic acids. This method circumvents additional synthetic steps required to prepare 2-azaaryl organometallics and organoborates as nucleophilic coupling partners, which are prone to protodemetallation and protodeborylation and produce potentially toxic byproducts.",
"doi": "10.1016/j.tet.2013.03.085",
"pmcid": "PMC3686134",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2013-07-08",
"series_number": "27-28",
"volume": "69",
"issue": "27-28",
"pages": "5732-5736"
},
{
"id": "authors:5w23w-htf68",
"collection": "authors",
"collection_id": "5w23w-htf68",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130813-101335730",
"type": "article",
"title": "Enantioselective Synthesis of the 5\u20136\u20137 Carbocyclic Core of the Gagunin Diterpenoids",
"author": [
{
"family_name": "Shibuya",
"given_name": "Grant M.",
"clpid": "Shibuya-Grant-M"
},
{
"family_name": "Enquist",
"given_name": "John A., Jr.",
"clpid": "Enquist-J-A-Jr"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic enantioselective double allylic alkylation reaction has been employed in the synthesis of the core of the gagunin diterpenoids. Enantioenriched material was advanced in 11 steps to afford the core of the highly oxygenated target, which includes two all-carbon quaternary stereocenters.",
"doi": "10.1021/ol401514s",
"pmcid": "PMC3743267",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2013-07-05",
"series_number": "13",
"volume": "15",
"issue": "13",
"pages": "3480-3483"
},
{
"id": "authors:zs90w-qqg50",
"collection": "authors",
"collection_id": "zs90w-qqg50",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130905-155148025",
"type": "article",
"title": "Selective Nucleic Acid Capture with Shielded Covalent Probes",
"author": [
{
"family_name": "Vieregg",
"given_name": "Jeffrey R.",
"clpid": "Vieregg-J-R"
},
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Pierce",
"given_name": "Niles A.",
"orcid": "0000-0003-2367-4406",
"clpid": "Pierce-N-A"
}
],
"abstract": "Nucleic acid probes are used for diverse applications in vitro, in situ, and in vivo. In any setting, their power is limited by imperfect selectivity (binding of undesired targets) and incomplete affinity (binding is reversible, and not all desired targets bound). These difficulties are fundamental, stemming from reliance on base pairing to provide both selectivity and affinity. Shielded covalent (SC) probes eliminate the longstanding trade-off between selectivity and durable target capture, achieving selectivity via programmable base pairing and molecular conformation change, and durable target capture via activatable covalent cross-linking. In pure and mixed samples, SC probes covalently capture complementary DNA or RNA oligo targets and reject two-nucleotide mismatched targets with near-quantitative yields at room temperature, achieving discrimination ratios of 2\u20133 orders of magnitude. Semiquantitative studies with full-length mRNA targets demonstrate selective covalent capture comparable to that for RNA oligo targets. Single-nucleotide DNA or RNA mismatches, including nearly isoenergetic RNA wobble pairs, can be efficiently rejected with discrimination ratios of 1\u20132 orders of magnitude. Covalent capture yields appear consistent with the thermodynamics of probe/target hybridization, facilitating rational probe design. If desired, cross-links can be reversed to release the target after capture. In contrast to existing probe chemistries, SC probes achieve the high sequence selectivity of a structured probe, yet durably retain their targets even under denaturing conditions. This previously incompatible combination of properties suggests diverse applications based on selective and stable binding of nucleic acid targets under conditions where base-pairing is disrupted (e.g., by stringent washes in vitro or in situ, or by enzymes in vivo).",
"doi": "10.1021/ja4009216",
"pmcid": "PMC3703666",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2013-07-03",
"series_number": "26",
"volume": "135",
"issue": "26",
"pages": "9691-9699"
},
{
"id": "authors:6h7r3-tz121",
"collection": "authors",
"collection_id": "6h7r3-tz121",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130809-133957166",
"type": "article",
"title": "Enantioselective Construction of \u03b1-Quaternary Cyclobutanones by Catalytic Asymmetric Allylic Alkylation",
"author": [
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-C-M"
},
{
"family_name": "Eidamshaus",
"given_name": "Christian",
"clpid": "Eidamshaus-C"
},
{
"family_name": "Kim",
"given_name": "Jimin",
"clpid": "Kim-Jimin"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "No strain, no gain! The first transition metal-catalyzed enantioselective \u03b1-alkylation of cyclobutanones is reported. This method employs palladium catalysis and an electron-deficient PHOX-type ligand to afford all-carbon \u03b1-quaternary cyclobutanones in good to excellent yields and enantioselectivities (see scheme).",
"doi": "10.1002/anie.201301815",
"pmcid": "PMC3817853",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2013-06-24",
"series_number": "26",
"volume": "52",
"issue": "26",
"pages": "6718-6721"
},
{
"id": "authors:k2dn3-h1j07",
"collection": "authors",
"collection_id": "k2dn3-h1j07",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130809-132636851",
"type": "article",
"title": "Total Syntheses of (-)-Transtaganolide A, (+)-Transtaganolide B, (+)-Transtaganolide C, and (-)-Transtaganolide D and Biosynthetic Implications",
"author": [
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Gordon",
"given_name": "Jonny R.",
"clpid": "Gordon-J-R"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "'Dibal'lin' on a budget: The enantioselective total syntheses of transtaganolides\u2005A\u2013D are rapidly achieved by a highly diastereoselective Ireland\u2013Claisen/Diels\u2013Alder cascade reaction of an enantioenriched geraniol derivative (see scheme). Based on X-ray diffraction data, the absolute configuration of these metabolites is established and discussed within the context of existing biosynthetic hypotheses.",
"doi": "10.1002/anie.201301212",
"pmcid": "PMC3825171",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2013-06-24",
"series_number": "26",
"volume": "52",
"issue": "26",
"pages": "6699-6703"
},
{
"id": "authors:929h5-qv978",
"collection": "authors",
"collection_id": "929h5-qv978",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130620-142930731",
"type": "article",
"title": "The Construction of All-Carbon Quaternary Stereocenters by Use of Pd-Catalyzed Asymmetric Allylic Alkylation Reactions in Total Synthesis",
"author": [
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "All-carbon quaternary stereocenters have posed significant challenges in the synthesis of complex natural products. These important structural motifs have inspired the development of broadly applicable palladium-catalyzed asymmetric allylic alkylation reactions of unstabilized non-biased enolates for the synthesis of enantioenriched \u03b1-quaternary products. This microreview outlines key considerations in the application of palladium-catalyzed asymmetric allylic alkylation reactions and presents recent total syntheses of complex natural products that have employed these powerful transformations for the direct, catalytic, enantioselective construction of all-carbon quaternary stereocenters.",
"doi": "10.1002/ejoc.201201761",
"pmcid": "PMC4059687",
"issn": "1434-193X",
"publisher": "Wiley-VCH Verlag",
"publication": "European Journal of Organic Chemistry",
"publication_date": "2013-05",
"series_number": "14",
"volume": "2013",
"issue": "14",
"pages": "2745-2759"
},
{
"id": "authors:9b6b1-bj247",
"collection": "authors",
"collection_id": "9b6b1-bj247",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130501-072844784",
"type": "article",
"title": "Expanding Insight into Asymmetric Palladium-Catalyzed Allylic Alkylation of N-Heterocyclic Molecules and Cyclic Ketones",
"author": [
{
"family_name": "Bennett",
"given_name": "Nathan B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Duquette",
"given_name": "Douglas C.",
"clpid": "Duquette-D-C"
},
{
"family_name": "Kim",
"given_name": "Jimin",
"clpid": "Kim-Jimin"
},
{
"family_name": "Liu",
"given_name": "Wen-Bo",
"orcid": "0000-0003-2687-557X",
"clpid": "Liu-Wen-Bo"
},
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-A-N"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Eeny, meeny, miny \u2026 enaminones! Lactams and imides have been shown to consistently provide enantioselectivities substantially higher than other substrate classes previously investigated in the palladium-catalyzed asymmetric decarboxylative allylic alkylation. Several new substrates have been designed to probe the contributions of electronic, steric, and stereoelectronic factors that distinguish the lactam/imide series as superior alkylation substrates (see scheme). These studies culminated in marked improvements on carbocyclic allylic alkylation substrates.",
"doi": "10.1002/chem.201300030",
"pmcid": "PMC3815597",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2013-04",
"series_number": "14",
"volume": "19",
"issue": "14",
"pages": "4414-4418"
},
{
"id": "authors:q6ky7-7fm06",
"collection": "authors",
"collection_id": "q6ky7-7fm06",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130410-144615697",
"type": "conference_item",
"title": "Development of a palladium-catalyzed enantioselective conjugate addition of arylboronic acids to cyclic conjugate acceptors",
"author": [
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Kikushima",
"given_name": "Kotaro",
"clpid": "Kikushima-Kotaro"
},
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-A-N"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters\nvia 1,4-addn. of arylboronic acids to \u03b2-substituted cyclic enones is reported. Reaction of a\nwide range of arylboronic acids and cyclic enones using a catalyst prepd. from Pd(OCOCF_3)_2 and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic\nstereocenters. Notably, this transformation is tolerant to air and moisture, providing a\npractical and operationally simple method of synthesizing enantioenriched all-carbon\nquaternary stereocenters.",
"publisher": "Caltech Library",
"publication_date": "2013-04"
},
{
"id": "authors:wtc74-vgz76",
"collection": "authors",
"collection_id": "wtc74-vgz76",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130501-082658216",
"type": "article",
"title": "Frequency Locked Microtoroid Optical Resonators as a Non-Invasive Tumor Biopsy Alternative",
"author": [
{
"family_name": "Su",
"given_name": "Judith",
"clpid": "Su-Judith"
},
{
"family_name": "Goldberg",
"given_name": "Alex",
"clpid": "Goldberg-A"
},
{
"family_name": "Raubitschek",
"given_name": "Andrew",
"clpid": "Raubitschek-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Fraser",
"given_name": "Scott E.",
"orcid": "0000-0002-5377-0223",
"clpid": "Fraser-S-E"
}
],
"abstract": "Whispering gallery mode optical resonators offer an unusual coupling of rapid response time and ultra-sensitive biological and chemical detection. We have improved the signal to noise ratio of microtoroid optical resonators \u223c1000-fold over standard techniques by using laser frequency locking and have applied this to assay tumor progression in mice by sensing the low concentrations of exosomes, shed by tumor cells, in serum samples collected from the animals. Serum samples from normal or experimental mice cause no shift in the resonance wavelength of the microtoroids; however, after using antibodies toward specific tumor markers to sensitize the toroid surface, we detected changes in the resonance frequency of the microtoroid when exposed to the serum of tumor-implanted mice. Serum from control (tumor-free) mice caused no shift. The wavelength shifts observed were 600 times the noise and drift of the sensor, even for a million fold dilution of the serum sample. Analysis of the shifts showed unitary steps of \u223c 0.5 fm, suggesting that the assay may be sensitive enough to detect individual binding events, offering a means to analyze the size of the biomolecules that are binding to the resonator. If validated, this approach offers a non-invasive tumor \"biopsy,\" exploiting the circulation of blood to collect a sample of tumor surfaces without the need to find or access the tumors.",
"doi": "10.1016/j.bpj.2012.11.2924",
"issn": "0006-3495",
"publisher": "Biophysical Society",
"publication": "Biophysical Journal",
"publication_date": "2013-01-29",
"series_number": "2",
"volume": "104",
"issue": "2",
"pages": "528A"
},
{
"id": "authors:7kq6g-x4v96",
"collection": "authors",
"collection_id": "7kq6g-x4v96",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130212-115138312",
"type": "article",
"title": "Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Heterocyclic Acceptors",
"author": [
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Marziale",
"given_name": "Alexander N.",
"clpid": "Marziale-A-N"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Mao",
"given_name": "Bin",
"clpid": "Mao-Bin"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Flava Flavanone: Asymmetric conjugate additions to chromones and 4-quinolones are reported utilizing a single catalyst system formed in situ from Pd(OCOCF_3)_2 and (S)-tBuPyOX. Notably, these reactions are performed in wet solvent under ambient atmosphere, and employ readily available arylboronic acids as the nucleophile, thus providing ready access to these asymmetric heterocycles.",
"doi": "10.1002/chem.201203643",
"pmcid": "PMC3753812",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2013-01-02",
"series_number": "1",
"volume": "19",
"issue": "1",
"pages": "74-77"
},
{
"id": "authors:bqqg6-k3909",
"collection": "authors",
"collection_id": "bqqg6-k3909",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130308-082047917",
"type": "article",
"title": "Rapid and Convergent Synthesis of a 2,4'-Linked Tri-oxazole in an Approach to Poly-oxazoles",
"author": [
{
"family_name": "Caspi",
"given_name": "Daniel D.",
"clpid": "Caspi-D-D"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Piller",
"given_name": "Fabian M.",
"clpid": "Piller-F-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A rapid and convergent synthesis of a 2,4'-linked tri-oxazole using a Negishi coupling is described.",
"doi": "10.3987/COM-12-S(N)118",
"issn": "0385-5414",
"publisher": "Japan Institute of Heterocyclic Chemistry",
"publication": "Heterocycles",
"publication_date": "2012-12-31",
"series_number": "2",
"volume": "86",
"issue": "2",
"pages": "1003-1008"
},
{
"id": "authors:8mf26-q5568",
"collection": "authors",
"collection_id": "8mf26-q5568",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130114-141639858",
"type": "article",
"title": "The Reaction Mechanism of the Enantioselective Tsuji Allylation: Inner-Sphere and Outer-Sphere Pathways, Internal Rearrangements, and Asymmetric C\u2013C Bond Formation",
"author": [
{
"family_name": "Keith",
"given_name": "John A.",
"orcid": "0000-0002-6583-6322",
"clpid": "Keith-J-A"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Sherden",
"given_name": "Nathaniel H.",
"clpid": "Sherden-N-H"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Ma",
"given_name": "Sandy",
"clpid": "Ma-Sandy"
},
{
"family_name": "Marinescu",
"given_name": "Smaranda C.",
"orcid": "0000-0003-2106-8971",
"clpid": "Marinescu-S-C"
},
{
"family_name": "Nielsen",
"given_name": "Robert J.",
"orcid": "0000-0002-7962-0186",
"clpid": "Nielsen-R-J"
},
{
"family_name": "Oxgaard",
"given_name": "Jonas",
"clpid": "Oxgaard-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
}
],
"abstract": "We use first principles quantum mechanics (density functional theory) to report a detailed reaction mechanism of the asymmetric Tsuji allylation involving prochiral nucleophiles and nonprochiral allyl fragments, which is consistent with experimental findings. The observed enantioselectivity is best explained with an inner-sphere mechanism involving the formation of a 5-coordinate Pd species that undergoes a ligand rearrangement, which is selective with regard to the prochiral faces of the intermediate enolate. Subsequent reductive elimination generates the product and a Pd^0 complex. The reductive elimination occurs via an unconventional seven-centered transition state that contrasts dramatically with the standard three-centered C\u2013C reductive elimination mechanism. Although limitations in the present theory prevent the conclusive identification of the enantioselective step, we note that three different computational schemes using different levels of theory all find that inner-sphere pathways are lower in energy than outer-sphere pathways. This result qualitatively contrasts with established allylation reaction mechanisms involving prochiral nucleophiles and prochiral allyl fragments. Energetic profiles of all reaction pathways are presented in detail.",
"doi": "10.1021/ja306860n",
"pmcid": "PMC3537505",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2012-11-21",
"series_number": "46",
"volume": "134",
"issue": "46",
"pages": "19050-19060"
},
{
"id": "authors:yhy88-2qc21",
"collection": "authors",
"collection_id": "yhy88-2qc21",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130107-104400691",
"type": "article",
"title": "Enantioselective Synthesis of a Hydroxymethyl-cis-1,3-cyclopentenediol Building Block",
"author": [
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-R-A-II"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-J-L"
},
{
"family_name": "Smith",
"given_name": "Russell C.",
"clpid": "Smith-R-C"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-A-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A brief, enantioselective synthesis of a hydroxymethyl-cis-1,3-cyclopentenediol building block is presented. This scaffold allows access to the cis-1,3-cyclopentanediol fragments found in a variety of biologically active natural and non-natural products. This rapid and efficient synthesis is highlighted by the utilization of the palladium-catalyzed enantioselective allylic alkylation of dioxanone substrates to prepare tertiary alcohols.",
"doi": "10.1021/ol3027297",
"pmcid": "PMC3506031",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2012-11-16",
"series_number": "22",
"volume": "14",
"issue": "22",
"pages": "5716-5719"
},
{
"id": "authors:vckhq-hd632",
"collection": "authors",
"collection_id": "vckhq-hd632",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130415-152954275",
"type": "book_section",
"title": "Catalytic Enantioselective Alkylation of Prochiral Ketone Enolates",
"book_title": "Asymmetric Synthesis II: More Methods and Applications",
"author": [
{
"family_name": "Reeves",
"given_name": "Corey M.",
"clpid": "Reeves-Corey-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"contributor": [
{
"family_name": "Christmann",
"given_name": "Mathias",
"clpid": "Christmann-Mathias"
},
{
"family_name": "Br\u00e4se",
"given_name": "Stefan",
"clpid": "Br\u00e4se-Stefan"
}
],
"abstract": "The synthesis of stereogenic all-carbon quaternary centers remains a formidable\nchallenge, notwithstanding the strides made by modem organic chemistry in this\nregard. Contemporary advances in enolate alkylation have made it a fundamental\nstrategy for the construction of C-C bonds. Although methods for the reaction\nof a number of enolate types (e.g., ester, ketone, and propionimide) with a variety of\nalkylating agents exist, catalytic enantioselective variants of these transformations\nare relatively rare. Of the catalytic asymmetric methods available, there have been\nfew examples of general techniques for the asymmetric alkylation of carbocyclic\nsystems and still fewer examples that have the capacity to deliver all-carbon\nquaternary stereocenters. While the Merck phase transfer methylation and Koga\nalkylation of 2-alkyltetralone-derived silyl enol ethers represent notable exceptions, the breadth of application and utility of these reactions bas been limited. In fact,\nat the outset of our investigations in this area, there were no examples of catalytic\nenantioselective alkylations of monocyclic 2-substituted cycloalkanone enolates in\nthe absence of either \u03b1'-blocking groups or \u03b1-enolate-stabilizing groups (e.g., R =\naryl, ester, etc.; Figure 1). Concurrent to our work in this area, Trost and coworkers have published a series of papers that complement our studies. Jacobsen and\ncoworkers, as well, have revealed a unique enantioselective method involving the\nchromium-catalyzed reaction of tin enolates with a variety of unactivated alkyl\nhalides . Herein, we relate our development of Pd-catalyzed enantioselective\nfunctionalization reactions of prochiral enolates, specifically tetrasubstituted cyclic\nketone enolates that give rise to quaternary stereogenicity. The synthetic utility\nof the building blocks derived from these reactions is demonstrated by application\nin a number of total syntheses.",
"doi": "10.1002/9783527652235.ch1",
"isbn": "9783527329212",
"publisher": "Wiley",
"place_of_publication": "Weinheim",
"publication_date": "2012-11-14",
"pages": "1-10"
},
{
"id": "authors:r53bj-08w44",
"collection": "authors",
"collection_id": "r53bj-08w44",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121203-103554504",
"type": "article",
"title": "Lewis Acid Mediated (3 + 2) Cycloadditions of Donor\u2013Acceptor Cyclopropanes with Heterocumulenes",
"author": [
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "O'Connor",
"given_name": "Nicholas R.",
"clpid": "O'Connor-N-R"
},
{
"family_name": "Craig",
"given_name": "Robert A., II",
"orcid": "0000-0002-2435-1564",
"clpid": "Craig-R-A-II"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Isocyanates, isothiocyanates, and carbodiimides are effective substrates in (3 + 2) cycloadditions with donor\u2013acceptor cyclopropanes for the synthesis of five-membered heterocycles. These reactions exhibit a broad substrate scope, high yields, and well-defined chemoselectivity. Discussed herein are the implications of Lewis acid choice on the stereochemical outcome and the reaction mechanism.",
"doi": "10.1021/ol302494n",
"pmcid": "PMC3490221",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2012-10-19",
"series_number": "20",
"volume": "14",
"issue": "20",
"pages": "5314-5317"
},
{
"id": "authors:k081z-9xj73",
"collection": "authors",
"collection_id": "k081z-9xj73",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141217-142148376",
"type": "article",
"title": "Enantioselective Total Synthesis of the Reported Structures of (\u2212)-9-epi-Presilphiperfolan-1-ol and (\u2212)-Presilphiperfolan-1-ol: Structural Confirmation and Reassignment and Biosynthetic Insights",
"author": [
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first total synthesis of the reported structures of 9-epi-presilphiperfolan-1-ol and presilphiperfolan-1-ol has been achieved. Key steps are a catalytic asymmetric alkylation of a novel diene-containing electrophile followed by a two-carbon ring contraction and an intramolecular Diels\u2013Alder cycloaddition to form the stereochemically dense tricyclic core. The synthetic work has resulted in the structural revision of presilphiperfolan-1-ol (see scheme).",
"doi": "10.1002/anie.201205276",
"pmcid": "PMC3517068",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2012-09-17",
"series_number": "38",
"volume": "51",
"issue": "38",
"pages": "9674-9678"
},
{
"id": "authors:5pf4t-nqk48",
"collection": "authors",
"collection_id": "5pf4t-nqk48",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121029-133109161",
"type": "article",
"title": "A C\u2013N insertion of \u03b2-lactam to benzyne: unusual formation of acridone",
"author": [
{
"family_name": "Kim",
"given_name": "Jimin",
"clpid": "Kim-Jimin"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Intermolecular insertion of benzyne into the C\u2013N bond of a \u03b2-lactam is described. This \u03c3-insertion is followed by ring expansion that produces dihydroquinolinone, which rapidly reacts with an additional benzyne unit to afford an acridone through intramolecular C\u2013C bond formation to the carbonyl group and rapid elimination of ethylene.",
"doi": "10.1016/j.tetlet.2012.07.026",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2012-09-12",
"series_number": "37",
"volume": "53",
"issue": "37",
"pages": "4994-4996"
},
{
"id": "authors:kvzzf-6zt90",
"collection": "authors",
"collection_id": "kvzzf-6zt90",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130516-140126410",
"type": "book_section",
"title": "Natural Products as Inspiration for Reaction Development: Catalytic Enantioselective Decarboxylative Reactions of Prochiral Enolate Equivalents",
"book_title": "Inventing reactions",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"contributor": [
{
"family_name": "Goo\u00dfen",
"given_name": "Lukas J.",
"clpid": "Goo\u00dfen-L-J"
}
],
"abstract": "This account describes the circumstances leading to our group's\ninnovations in the area of decarboxylative asymmetric allylic alkylation reactions\nand the initial discovery of palladium phosphinooxazoline complexes as efficient\nenantioselective catalysts. This chapter also chronicles the growth of the methodology\nto include several substrate classes, the expansion of the project into several other\nreaction manifolds, and the use of these reactions in natural product synthesis. Finally,\nimportant contributions from other research groups involving related methods or\nproducts similar to the \u03b1-quaternary products that are the focus of our studies, as\nwell as future directions for asymmetric alkylation reactions, are discussed.",
"doi": "10.1007/3418_2012_49",
"isbn": "978-3-642-34285-1",
"publisher": "Springer-Verlag",
"place_of_publication": "Berlin",
"publication_date": "2012-08-18",
"pages": "281-314"
},
{
"id": "authors:t15s3-y5q40",
"collection": "authors",
"collection_id": "t15s3-y5q40",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120822-154455462",
"type": "conference_item",
"title": "Sensitive and selective nucleic acid capture with shielded covalent probes",
"author": [
{
"family_name": "Vieregg",
"given_name": "Jeffrey R.",
"clpid": "Vieregg-Jeffrey-R"
},
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Pierce",
"given_name": "Niles A.",
"orcid": "0000-0003-2367-4406",
"clpid": "Pierce-N-A"
}
],
"abstract": "Nucleic acid probes are used for diverse applications in vitro, in situ, and in vivo. In any setting, their power is limited by imperfect selectivity (binding of undesired targets) and incomplete affinity (binding is reversible and not all desired targets are bound). These limitations stem from reliance on base pairing to both reject off-targets and retain desired targets. To address this selectivity/affinity tradeoff, shielded covalent probes achieve selectivity via conformation change and durable capture via covalent crosslinking of a photoactive nucleoside analog. In vitro assays show that mismatches are efficiently rejected and desired targets are durably captured. For probes designed to reject two-nucleotide mismatches, desired targets are captured nearly quant. Single-nucleotide mismatches are discriminated near the thermodn. limit. The probes operate isothermally and crosslinking activation is rapid with low-cost light sources. If desired, crosslinks can be reversed to release the target after capture. We envision a wide array of applications.",
"publisher": "Caltech Library",
"publication_date": "2012-08"
},
{
"id": "authors:gs4vt-fgw87",
"collection": "authors",
"collection_id": "gs4vt-fgw87",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120822-092222870",
"type": "conference_item",
"title": "Novel approach to antitumor antibiotics: Using the power of benzyne in synthesis",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We have initiated a research program directed toward the tetrahydroisoquinoline (THIQ) antitumor antibiotics, a class of bioactive alkaloids with existing clin. applications. Central to our approach is the development of new aryne annulation methods for the synthesis of isoquinolines. Our initial application of this method in a THIQ synthesis was to a concise asym. total synthesis of (-)-quinocarcin. Our current work in the area will be discussed.",
"publisher": "Caltech Library",
"publication_date": "2012-08"
},
{
"id": "authors:cbt0t-gsa17",
"collection": "authors",
"collection_id": "cbt0t-gsa17",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120712-093347151",
"type": "article",
"title": "A Comprehensive History of Arynes in Natural Product Total\n Synthesis",
"author": [
{
"family_name": "Tadross",
"given_name": "Pamela M.",
"clpid": "Tadross-P-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Within 14 years of the seminal experiments of J. D. Roberts\nleading to the first proposal of the structure of benzyne (1), synthetic organic chemists recognized the potential to exploit this highly reactive intermediate (and its substituted variants) in the total synthesis of natural products. More specifically, it was recognized that arynes offered the strategic advantage of rapidly functionalizing an aromatic ring by forming multiple carbon\u2212 carbon or carbon\u2212heteroatom bonds in a single operation, often in a regioselective manner. Initially, the scope of synthetic\napplications was somewhat limited by the harsh conditions\nrequired to produce the aryne species. Many of these methods required strong bases, such as n-BuLi, or high temperatures (Scheme 1). However, with the development of milder methods for the generation of arynes came increased interest in employing them in the synthesis of more complex polycyclic systems. Most recently, the use of o-silyl aryl triflates as aryne precursors has allowed generation of the reactive intermediate under almost neutral conditions.\nTo date, over 75 individual natural products have been\nprepared using arynes to generate key synthetic intermediates. Herein are recounted the reports of total syntheses that utilize arynes in ways that build complexity or introduce motifs essential to the completion of their targets. The methods by which the authors featured in this review accomplish this task reflect the versatility of arynes as reactive intermediates for synthesis (Scheme 2). For the purposes of organization, the syntheses are divided into subgroups on the basis of the type of aryne transformation: (i) nucleophilic additions or multicomponent reactions, (ii) \u03c3-bond insertion reactions, (iii) [4 + 2]- and [2 + 2]-cycloaddition strategies, and (iv) metal-catalyzed aryne reactions.",
"doi": "10.1021/cr200478h",
"issn": "0009-2665",
"publisher": "American Chemical Society",
"publication": "Chemical Reviews",
"publication_date": "2012-06",
"series_number": "6",
"volume": "112",
"issue": "6",
"pages": "3550-3577"
},
{
"id": "authors:stzcb-yjd46",
"collection": "authors",
"collection_id": "stzcb-yjd46",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120126-101327960",
"type": "article",
"title": "Enantioselective construction of quaternary N-heterocycles by palladium-catalysed decarboxylative allylic alkylation of lactams",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Liu",
"given_name": "Yiyang",
"clpid": "Liu-Yiyang"
},
{
"family_name": "Yurino",
"given_name": "Taiga",
"clpid": "Yurino-Taiga"
},
{
"family_name": "Kim",
"given_name": "Jimin",
"clpid": "Kim-Jimin"
},
{
"family_name": "White",
"given_name": "David E.",
"clpid": "White-D-E"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The enantioselective synthesis of nitrogen-containing heterocycles (N-heterocycles) represents a substantial chemical research effort and resonates across numerous disciplines, including the total synthesis of natural products and medicinal chemistry. In this Article, we describe the highly enantioselective palladium-catalysed decarboxylative allylic alkylation of readily available lactams to form 3,3-disubstituted pyrrolidinones, piperidinones, caprolactams and structurally related lactams. Given the prevalence of quaternary N-heterocycles in biologically active alkaloids and pharmaceutical agents, we envisage that our method will provide a synthetic entry into the de novo asymmetric synthesis of such structures. As an entry for these investigations we demonstrate how the described catalysis affords enantiopure quaternary lactams that intercept synthetic intermediates previously used in the synthesis of the Aspidosperma alkaloids quebrachamine and rhazinilam, but that were previously only available by chiral auxiliary approaches or as racemic mixtures.",
"doi": "10.1038/nchem.1222",
"pmcid": "PMC3266627",
"issn": "1755-4330",
"publisher": "Nature Publishing Group",
"publication": "Nature Chemistry",
"publication_date": "2012-02",
"series_number": "2",
"volume": "4",
"issue": "2",
"pages": "130-133"
},
{
"id": "authors:52g5t-nh612",
"collection": "authors",
"collection_id": "52g5t-nh612",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20111021-144400118",
"type": "article",
"title": "Synthesis of enantioenriched \u03b3-quaternary cycloheptenones using a combined allylic alkylation/Stork\u2013Danheiser approach: preparation of mono-, bi-, and tricyclic systems",
"author": [
{
"family_name": "Bennett",
"given_name": "Nathan B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-A-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A general method for the synthesis of \u03b2-substituted and unsubstituted cycloheptenones bearing enantioenriched all-carbon \u03b3-quaternary stereocenters is reported. Hydride or organometallic addition to a seven-membered ring vinylogous ester followed by finely tuned quenching parameters achieves elimination to the corresponding cycloheptenone. The resulting enones are elaborated to bi- and tricyclic compounds with potential for the preparation of non-natural analogs and whose structures are embedded in a number of cycloheptanoid natural products.",
"doi": "10.1039/C1OB06189E",
"pmcid": "PMC3365663",
"issn": "1477-0520",
"publisher": "Royal Society of Chemistry",
"publication": "Organic and Biomolecular Chemistry",
"publication_date": "2012-01-07",
"series_number": "1",
"volume": "10",
"issue": "1",
"pages": "56-59"
},
{
"id": "authors:zfhad-8zd23",
"collection": "authors",
"collection_id": "zfhad-8zd23",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120124-111234894",
"type": "article",
"title": "Palladium-catalyzed asymmetric alkylation in the synthesis of cyclopentanoid and cycloheptanoid core structures bearing all-carbon quaternary stereocenters",
"author": [
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Bennett",
"given_name": "Nathan B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "Jensen",
"given_name": "Thomas",
"clpid": "Jensen-Thomas"
},
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-A-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "General catalytic asymmetric routes toward cyclopentanoid and cycloheptanoid core structures embedded in numerous natural products have been developed. The central stereoselective transformation in our divergent strategies is the enantioselective decarboxylative alkylation of seven-membered \u03b2-ketoesters to form \u03b1-quaternary vinylogous esters. Recognition of the unusual reactivity of \u03b2-hydroxyketones resulting from the addition of hydride or organometallic reagents enabled divergent access to\ny-quaternary acylcyclopentenes through a ring contraction pathway or y-quaternary cycloheptenones through a carbonyl transposition pathway. Synthetic applications of these compounds were explored through the preparation of mono-, bi-, and tricyclic derivatives that can serve as valuable intermediates for the total synthesis of complex natural products. This work complements our previous work with\ncyclohexanoid systems.",
"doi": "10.1016/j.tet.2011.10.031",
"pmcid": "PMC3279929",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2011-12-30",
"series_number": "52",
"volume": "67",
"issue": "52",
"pages": "10234-10248"
},
{
"id": "authors:1r29d-kdb59",
"collection": "authors",
"collection_id": "1r29d-kdb59",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120214-111558996",
"type": "article",
"title": "Enantioselective Decarboxylative Alkylation Reactions: Catalyst Development, Substrate Scope, and Mechanistic Studies",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Sherden",
"given_name": "Nathaniel H.",
"clpid": "Sherden-N-H"
},
{
"family_name": "Marinescu",
"given_name": "Smaranda C.",
"orcid": "0000-0003-2106-8971",
"clpid": "Marinescu-S-C"
},
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-A-M"
},
{
"family_name": "Tani",
"given_name": "Kousuke",
"clpid": "Tani-Kousuke"
},
{
"family_name": "Seto",
"given_name": "Masaki",
"clpid": "Seto-Masaki"
},
{
"family_name": "Ma",
"given_name": "Sandy",
"clpid": "Ma-Sandy"
},
{
"family_name": "Nov\u00e1k",
"given_name": "Zolt\u00e1n",
"clpid": "Nov\u00e1k-Z"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "McFadden",
"given_name": "Ryan M.",
"clpid": "McFadden-R-M"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-J-L"
},
{
"family_name": "Enquist",
"given_name": "John A., Jr.",
"clpid": "Enquist-J-A-Jr"
},
{
"family_name": "White",
"given_name": "David E.",
"clpid": "White-D-E"
},
{
"family_name": "Levine",
"given_name": "Samantha R.",
"clpid": "Levine-S-R"
},
{
"family_name": "Petrova",
"given_name": "Krastina V.",
"clpid": "Petrova-K-V"
},
{
"family_name": "Iwashita",
"given_name": "Akihiko",
"clpid": "Iwashita-Akihiko"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "\u03b1-Quaternary ketones are accessed through novel enantioselective alkylations of allyl and propargyl electrophiles by unstabilized prochiral enolate nucleophiles in the presence of palladium complexes with various phosphinooxazoline (PHOX) ligands. Excellent yields and high enantiomeric excesses are obtained from three classes of enolate precursor: enol carbonates, enol silanes, and racemic \u03b2-ketoesters. Each of these substrate classes functions with nearly identical efficiency in terms of yield and enantioselectivity. Catalyst discovery and development, the optimization of reaction conditions, the exploration of reaction scope, and applications in target-directed synthesis are reported. Experimental observations suggest that these alkylation reactions occur through an unusual inner-sphere mechanism involving binding of the prochiral enolate nucleophile directly to the palladium center.",
"doi": "10.1002/chem.201003383",
"pmcid": "PMC3365686",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2011-12-09",
"series_number": "50",
"volume": "17",
"issue": "50",
"pages": "14199-14223"
},
{
"id": "authors:ra5tx-qan62",
"collection": "authors",
"collection_id": "ra5tx-qan62",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20111107-115520974",
"type": "article",
"title": "Total Syntheses of Cyanthiwigins B, F, and G",
"author": [
{
"family_name": "Enquist",
"given_name": "John A., Jr.",
"clpid": "Enquist-J-A-Jr"
},
{
"family_name": "Virgil",
"given_name": "Scot C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A concise and versatile approach toward the preparation of the cyanthiwigin family of cyathane natural products is described. By leveraging a unique double asymmetric catalytic alkylation procedure it is possible to quickly establish two of the most critical stereocenters of the cyanthiwigin framework with high levels of selectivity and expediency. The synthetic route additionally employs both a tandem ring-closing cross-metathesis reaction, and an aldehyde-olefin radical cyclization process, in order to rapidly arrive at the tricyclic cyathane core of the cyanthiwigin molecules. From this unifying intermediate, the preparations of cyanthiwigins B, F, and G are attained swiftly and without the need for protecting groups.",
"doi": "10.1002/chem.201100425",
"pmcid": "PMC3365662",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2011-08-29",
"series_number": "36",
"volume": "17",
"issue": "36",
"pages": "9957-9969"
},
{
"id": "authors:28hpq-y1z24",
"collection": "authors",
"collection_id": "28hpq-y1z24",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110912-114011217",
"type": "article",
"title": "A Palladium-Catalyzed Vinylcyclopropane (3 + 2) Cycloaddition Approach to the Melodinus Alkaloids",
"author": [
{
"family_name": "Goldberg",
"given_name": "Alexander F. G.",
"clpid": "Goldberg-A-F-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A palladium-catalyzed (3 + 2) cycloaddition of a vinylcyclopropane and a \u03b2-nitrostyrene is employed to rapidly assemble the cyclopentane core of the Melodinus alkaloids. The ABCD ring system of the natural product family is prepared in six steps from commercially available materials.",
"doi": "10.1021/ol2017615",
"pmcid": "PMC3155617",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2011-08-19",
"series_number": "16",
"volume": "13",
"issue": "16",
"pages": "4474-4476"
},
{
"id": "authors:gb3kb-bwf45",
"collection": "authors",
"collection_id": "gb3kb-bwf45",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110808-112210599",
"type": "article",
"title": "A rapid and convergent synthesis of the integrastatin core",
"author": [
{
"family_name": "Tadross",
"given_name": "Pamela M.",
"clpid": "Tadross-P-M"
},
{
"family_name": "Bugga",
"given_name": "Pradeep",
"clpid": "Bugga-P"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The tetracyclic core of the integrastatin natural products has\nbeen prepared in a convergent and rapidmanner. Our strategy\nrelies upon a palladium(II)-catalyzed oxidative cyclization to\nform the central [3.3.1]-dioxabicycle of the natural product\ncore. Overall, the core has been completed in only 4 linear\nsteps from known compounds.",
"doi": "10.1039/c1ob05725a",
"issn": "1477-0520",
"publisher": "Royal Society of Chemistry",
"publication": "Organic and Biomolecular Chemistry",
"publication_date": "2011-08-07",
"series_number": "15",
"volume": "9",
"issue": "15",
"pages": "5354-5357"
},
{
"id": "authors:t48dv-z4w28",
"collection": "authors",
"collection_id": "t48dv-z4w28",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110622-115436125",
"type": "article",
"title": "The Catalytic Enantioselective Total Synthesis of (+)-Liphagal",
"author": [
{
"family_name": "Day",
"given_name": "Joshua J.",
"clpid": "Day-J-J"
},
{
"family_name": "McFadden",
"given_name": "Ryan M.",
"clpid": "McFadden-R-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Kolding",
"given_name": "Helene",
"clpid": "Kolding-H"
},
{
"family_name": "Alleva",
"given_name": "Jennifer L.",
"clpid": "Alleva-J-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Ring a ding: The meroterpenoid natural product (+)-liphagal has been synthesized enantioselectively in 19 steps from commercially available materials. The trans-homodecalin system was achieved by ring expansion followed by stereoselective hydrogenation.",
"doi": "10.1002/anie.201101842",
"pmcid": "PMC3361906",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2011-07-18",
"series_number": "30",
"volume": "50",
"issue": "30",
"pages": "6814-6818"
},
{
"id": "authors:tje8k-f3h87",
"collection": "authors",
"collection_id": "tje8k-f3h87",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110706-135043254",
"type": "article",
"title": "Palladium-catalyzed, asymmetric Baeyer\u2013Villiger oxidation of prochiral cyclobutanones with PHOX ligands",
"author": [
{
"family_name": "Petersen",
"given_name": "Kimberly S.",
"clpid": "Petersen-K-S"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Described in this report is a general method for the conversion of prochiral 3-substituted cyclobutanones to enantioenriched \u03b3-lactones through a palladium-catalyzed Baeyer\u2013Villiger oxidation using phosphinooxazoline ligands in up to 99% yield and 81% ee. Lactones of enantiopurity \u2265 93% could be obtained through a single recrystallization step. Importantly, 3,3-disubtituted cyclobutanones produced enantioenriched lactones containing a \u03b2-quaternary center.",
"doi": "10.1016/j.tet.2011.04.046",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2011-06-17",
"series_number": "24",
"volume": "67",
"issue": "24",
"pages": "4352-4357"
},
{
"id": "authors:ckv8b-snr71",
"collection": "authors",
"collection_id": "ckv8b-snr71",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110608-104503600",
"type": "article",
"title": "Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Five-, Six-, and Seven-Membered \u03b2-Substituted Cyclic Enones: Enantioselective Construction of All-Carbon Quaternary Stereocenters",
"author": [
{
"family_name": "Kikushima",
"given_name": "Kotaro",
"clpid": "Kikushima-Kotaro"
},
{
"family_name": "Holder",
"given_name": "Jeffrey C.",
"clpid": "Holder-J-C"
},
{
"family_name": "Gatti",
"given_name": "Michele",
"clpid": "Gatti-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4-addition of arylboronic acids to \u03b2-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF_3)_2 and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this transformation is tolerant to air and moisture, providing a practical and operationally simple method of synthesizing enantioenriched all-carbon quaternary stereocenters.",
"doi": "10.1021/ja200664x",
"pmcid": "PMC3087848",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2011-05-11",
"series_number": "18",
"volume": "133",
"issue": "18",
"pages": "6902-6905"
},
{
"id": "authors:jxwpk-wy806",
"collection": "authors",
"collection_id": "jxwpk-wy806",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110606-080601724",
"type": "article",
"title": "Benzannulated Bicycles by Three-Component Aryne Reactions",
"author": [
{
"family_name": "Allan",
"given_name": "Kevin M.",
"orcid": "0000-0002-7750-3621",
"clpid": "Allan-K-M"
},
{
"family_name": "Gilmore",
"given_name": "Christopher D.",
"clpid": "Gilmore-C-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Triple crown: A pair of three-component coupling reactions between arynes, isocyanides, and either activated alkynes or phenyl esters generates unusual iminoindenones or phenoxy iminoisobenzofurans (see scheme), the latter of which may be advanced to o-ketobenzamides by performing direct hydrolysis. The synthetic utility of these compounds is demonstrated in a rapid preparation of substituted dibenzoketocaprolactams.",
"doi": "10.1002/anie.201100911",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2011-05-02",
"series_number": "19",
"volume": "50",
"issue": "19",
"pages": "4488-4491"
},
{
"id": "authors:emzfv-9gb31",
"collection": "authors",
"collection_id": "emzfv-9gb31",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110526-081657895",
"type": "article",
"title": "Confirmation of the absolute configuration of (-)-aurantioclavine",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Krishnan",
"given_name": "Shyam",
"clpid": "Krishnan-Shyam"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We confirm our previous assignment of the absolute configuration of (\u2212)-aurantioclavine as 7R by crystallographically characterizing an advanced 3-bromoindole intermediate reported in our previous synthesis. This analysis also provides additional support for our model of enantioinduction in the palladium(II)-catalyzed oxidative kinetic resolution of secondary alcohols.",
"doi": "10.1016/j.tetlet.2010.11.074",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2011-04-27",
"series_number": "17",
"volume": "52",
"issue": "17",
"pages": "2152-2154"
},
{
"id": "authors:dzn75-v8c19",
"collection": "authors",
"collection_id": "dzn75-v8c19",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110404-113128218",
"type": "article",
"title": "A General Approach to the Basiliolide/Transtaganolide Natural Products: Total Syntheses of Basiliolide B, epi-8-Basiliolide B, Transtaganolide C, and Transtaganolide D",
"author": [
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Murakami",
"given_name": "Kei",
"clpid": "Murakami-Kei"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "In a flash: The total synthesis of transtaganolide and basiliolide natural products is achieved in three steps from achiral, monocyclic esters (see scheme). Featured in the syntheses are an Ireland-Claisen/Diels\u2013Alder cascade and a novel methoxyacetylide coupling/cyclization sequence.",
"doi": "10.1002/anie.201008003",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2011-04-11",
"series_number": "16",
"volume": "50",
"issue": "16",
"pages": "3688-3691"
},
{
"id": "authors:yvmyy-ta554",
"collection": "authors",
"collection_id": "yvmyy-ta554",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110414-085357247",
"type": "article",
"title": "Reversible inhibitor of p97, DBeQ, impairs both ubiquitin-dependent and autophagic protein clearance pathways",
"author": [
{
"family_name": "Chou",
"given_name": "Tsui-Fen",
"orcid": "0000-0003-2410-2186",
"clpid": "Chou-Tsui-Fen"
},
{
"family_name": "Brown",
"given_name": "Steve J.",
"clpid": "Brown-S-J"
},
{
"family_name": "Minond",
"given_name": "Dmitriy",
"clpid": "Minond-D"
},
{
"family_name": "Nordin",
"given_name": "Brian E.",
"clpid": "Nordin-B-E"
},
{
"family_name": "Li",
"given_name": "Kelin",
"clpid": "Li-Kelin"
},
{
"family_name": "Jones",
"given_name": "Amanda C.",
"orcid": "0000-0001-8426-8407",
"clpid": "Jones-A-C"
},
{
"family_name": "Chase",
"given_name": "Peter",
"clpid": "Chase-P"
},
{
"family_name": "Porubsky",
"given_name": "Patrick R.",
"clpid": "Porubsky-P-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Schoenen",
"given_name": "Frank J.",
"clpid": "Schoenen-F-J"
},
{
"family_name": "Patricelli",
"given_name": "Matthew P.",
"clpid": "Patricelli-M-P"
},
{
"family_name": "Hodder",
"given_name": "Peter",
"clpid": "Hodder-P"
},
{
"family_name": "Rosen",
"given_name": "Hugh",
"clpid": "Rosen-H"
},
{
"family_name": "Deshaies",
"given_name": "Raymond J.",
"orcid": "0000-0002-3671-9354",
"clpid": "Deshaies-R-J"
}
],
"abstract": "A specific small-molecule inhibitor of p97 would provide an important tool to investigate diverse functions of this essential ATPase associated with diverse cellular activities (AAA) ATPase and to evaluate its potential to be a therapeutic target in human disease. We carried out a high-throughput screen to identify inhibitors of p97 ATPase activity. Dual-reporter cell lines that simultaneously express p97-dependent and p97-independent proteasome substrates were used to stratify inhibitors that emerged from the screen. N^2,N^4-dibenzylquinazoline-2,4-diamine (DBeQ) was identified as a selective, potent, reversible, and ATP-competitive p97 inhibitor. DBeQ blocks multiple processes that have been shown by RNAi to depend on p97, including degradation of ubiquitin fusion degradation and endoplasmic reticulum-associated degradation pathway reporters, as well as autophagosome maturation. DBeQ also potently inhibits cancer cell growth and is more rapid than a proteasome inhibitor at mobilizing the executioner caspases-3 and -7. Our results provide a rationale for targeting p97 in cancer therapy.",
"doi": "10.1073/pnas.1015312108",
"pmcid": "PMC3064330",
"issn": "0027-8424",
"publisher": "National Academy of Sciences",
"publication": "Proceedings of the National Academy of Sciences of the United States of America",
"publication_date": "2011-03-22",
"series_number": "12",
"volume": "108",
"issue": "12",
"pages": "4834-4839"
},
{
"id": "authors:qzpkg-x0534",
"collection": "authors",
"collection_id": "qzpkg-x0534",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110329-133407762",
"type": "article",
"title": "Ring-Contraction Strategy for the Practical, Scalable, Catalytic Asymmetric Synthesis of Versatile \u03b3-Quaternary Acylcyclopentenes",
"author": [
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "Jensen",
"given_name": "Thomas",
"clpid": "Jensen-Thomas"
},
{
"family_name": "Bennett",
"given_name": "Nathan B.",
"clpid": "Bennett-N-B"
},
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-A-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Contraction action! A simple protocol for the catalytic asymmetric synthesis of highly functionalized \u03b3-quaternary acylcyclopentenes (see schematic) in up to 91\u2009% overall yield and 92\u2009% ee has been developed. The reaction sequence employs a palladium-catalyzed enantioselective alkylation reaction and exploits the unusual stability of \u03b2-hydroxy cycloheptanones to achieve a general and robust method for performing two-carbon ring contractions.",
"doi": "10.1002/anie.201007814",
"pmcid": "PMC3365661",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2011-03-14",
"series_number": "12",
"volume": "50",
"issue": "12",
"pages": "2756-2760"
},
{
"id": "authors:sankn-wtx37",
"collection": "authors",
"collection_id": "sankn-wtx37",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110201-085102866",
"type": "article",
"title": "A Catalytic, Asymmetric Formal Synthesis of (+)-Hamigeran B",
"author": [
{
"family_name": "Mukherjee",
"given_name": "Herschel",
"clpid": "Mukherjee-H"
},
{
"family_name": "McDougal",
"given_name": "Nolan T.",
"clpid": "McDougal-N-T"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A concise asymmetric, formal synthesis of (+)-hamigeran B is reported. A Pd-catalyzed, decarboxylative allylic alkylation, employing a trifluoromethylated derivative of t-BuPHOX, is utilized as the enantioselective step to form the critical quaternary carbon center in excellent yield and enantioselectivity. The product is converted in three steps to a late-stage intermediate previously used in the synthesis of hamigeran B.",
"doi": "10.1021/ol102669z",
"pmcid": "PMC3045637",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2011-03-04",
"series_number": "5",
"volume": "13",
"issue": "5",
"pages": "825-827"
},
{
"id": "authors:pz0h8-44h96",
"collection": "authors",
"collection_id": "pz0h8-44h96",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120816-071730866",
"type": "conference_item",
"title": "Complex natural products as a driving force for discovery in organic chemistry",
"author": [
{
"family_name": "Stoltz",
"given_name": "B. M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "This lecture will focus on the development of new catalytic bond forming reactions developed in our lab and applications\nin complex mol. synthesis.",
"publisher": "Caltech Library",
"publication_date": "2010-12"
},
{
"id": "authors:hj73z-bq429",
"collection": "authors",
"collection_id": "hj73z-bq429",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120815-153559315",
"type": "conference_item",
"title": "Intertwined nature of chemical synthesis and the discovery process",
"author": [
{
"family_name": "Stoltz",
"given_name": "B. M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "This lecture will describe recent advances in our lab. in the area of asym. catalysis and applications in multi-step\nsynthesis.",
"publisher": "Caltech Library",
"publication_date": "2010-12"
},
{
"id": "authors:tgvcb-d4a11",
"collection": "authors",
"collection_id": "tgvcb-d4a11",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101103-104745366",
"type": "article",
"title": "Rapid synthesis of an electron-deficient t-BuPHOX ligand: cross-coupling of aryl bromides with secondary phosphine oxides",
"author": [
{
"family_name": "McDougal",
"given_name": "Nolan T.",
"clpid": "McDougal-N-T"
},
{
"family_name": "Streuff",
"given_name": "Jan",
"clpid": "Streuff-J"
},
{
"family_name": "Mukherjee",
"given_name": "Herschel",
"clpid": "Mukherjee-H"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein an efficient and direct copper-catalyzed coupling of oxazoline-containing aryl bromides with electron-deficient secondary phosphine oxides is reported. The resulting tertiary phosphine oxides can be reduced to prepare a range of PHOX ligands. The presented strategy is a useful alternative to known methods for constructing PHOX derivatives.",
"doi": "10.1016/j.tetlet.2010.08.039",
"pmcid": "PMC2976555",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2010-10-20",
"series_number": "42",
"volume": "51",
"issue": "42",
"pages": "5550-5554"
},
{
"id": "authors:j81gc-pbs33",
"collection": "authors",
"collection_id": "j81gc-pbs33",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141217-164835707",
"type": "article",
"title": "Welwitindolinone C synthetic studies. Construction of the welwitindolinone carbon skeleton via a transannular nitrone cycloaddition",
"author": [
{
"family_name": "Freeman",
"given_name": "David B.",
"clpid": "Freeman-D-B"
},
{
"family_name": "Holubec",
"given_name": "Alexandra A.",
"clpid": "Holubec-A-A"
},
{
"family_name": "Weiss",
"given_name": "Matthew W.",
"clpid": "Weiss-M-W"
},
{
"family_name": "Dixon",
"given_name": "Julia A.",
"clpid": "Dixon-J-A"
},
{
"family_name": "Kakefuda",
"given_name": "Akio",
"clpid": "Kakefuda-Akio"
},
{
"family_name": "Ohtsuka",
"given_name": "Masami",
"clpid": "Ohtsuka-Masami"
},
{
"family_name": "Inoue",
"given_name": "Munenori",
"clpid": "Inoue-Munenori"
},
{
"family_name": "Vaswani",
"given_name": "Rishi G.",
"clpid": "Vaswani-R-G"
},
{
"family_name": "Ohki",
"given_name": "Hidenori",
"clpid": "Ohki-Hidenori"
},
{
"family_name": "Doan",
"given_name": "Brian D.",
"clpid": "Doan-B-D"
},
{
"family_name": "Reisman",
"given_name": "Sarah E.",
"orcid": "0000-0001-8244-9300",
"clpid": "Reisman-S-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Day",
"given_name": "Joshua J.",
"clpid": "Day-J-J"
},
{
"family_name": "Tao",
"given_name": "Ran N.",
"clpid": "Tao-Ran-N"
},
{
"family_name": "Dieterich",
"given_name": "Noah A.",
"clpid": "Dieterich-N-A"
},
{
"family_name": "Wood",
"given_name": "John L.",
"clpid": "Wood-J-L"
}
],
"abstract": "Described is the construction of the N-methylwelwitindolinone C core via an efficient strategy that employs a sequential rhodium carbenoid-mediated O\u2013H insertion, Claisen rearrangement and transannular [3+2] nitrone cycloaddition.",
"doi": "10.1016/j.tet.2010.04.131",
"pmcid": "PMC2924776",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2010-08-14",
"series_number": "33",
"volume": "66",
"issue": "33",
"pages": "6647-6655"
},
{
"id": "authors:k6v0m-t8h28",
"collection": "authors",
"collection_id": "k6v0m-t8h28",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100713-135750673",
"type": "article",
"title": "High-Throughput Screening of the Asymmetric Decarboxylative Alkylation Reaction of Enolate-Stabilized Enol Carbonates",
"author": [
{
"family_name": "McDougal",
"given_name": "Nolan T.",
"clpid": "McDougal-N-T"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The use of high-throughput screening allowed for the optimization of reaction conditions for the palladium-catalyzed asymmetric decarboxylative alkylation reaction of enolate-stabilized enol carbonates. Changing to a nonpolar reaction solvent and to an electron-deficient PHOX derivative as ligand from our standard \u00adreaction conditions improved the enantioselectivity for the alkylation of a ketal-protected,1,3-diketone-derived enol carbonate from 28% ee to 84% ee. Similar improvements in enantioselectivity were seen for a \u03b2-keto ester derived and an \u03b1-phenyl cyclohexanone-\u00adderived enol carbonate.",
"doi": "10.1055/s-0030-1258094",
"pmcid": "PMC2976558",
"issn": "0936-5214",
"publisher": "Georg Thieme Verlag",
"publication": "Synlett",
"publication_date": "2010-07",
"series_number": "11",
"volume": "2010",
"issue": "11",
"pages": "1712-1716"
},
{
"id": "authors:2619s-fxx22",
"collection": "authors",
"collection_id": "2619s-fxx22",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100601-110245242",
"type": "article",
"title": "Efforts toward rapid construction of the cortistatin A carbocyclic core via enyne-ene metathesis",
"author": [
{
"family_name": "Baumgartner",
"given_name": "Corinne",
"clpid": "Baumgartner-C"
},
{
"family_name": "Ma",
"given_name": "Sandy",
"clpid": "Ma-Sandy"
},
{
"family_name": "Liu",
"given_name": "Qi",
"clpid": "Liu-Qi"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Our efforts toward the construction of the carbocylic core of cortistatin A via an enyne-ene metathesis are\ndisclosed. Interestingly, an attempted S_N2 inversion of a secondary mesylate in our five-membered D-ring piece\ngave a product with retention of stereochemistry.",
"doi": "10.1039/c004275g",
"issn": "1477-0520",
"publisher": "Royal Society of Chemistry",
"publication": "Organic and Biomolecular Chemistry",
"publication_date": "2010-06-28",
"series_number": "13",
"volume": "8",
"issue": "13",
"pages": "2915-2917"
},
{
"id": "authors:7dbd7-akf31",
"collection": "authors",
"collection_id": "7dbd7-akf31",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100712-150605717",
"type": "article",
"title": "A general enantioselective route to the chamigrene natural product family",
"author": [
{
"family_name": "White",
"given_name": "David E.",
"clpid": "White-D-E"
},
{
"family_name": "Stewart",
"given_name": "Ian C.",
"clpid": "Stewart-I-C"
},
{
"family_name": "Seashore-Ludlow",
"given_name": "Brinton A.",
"clpid": "Seashore-Ludlow-B-A"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Described in this report is an enantioselective route toward the chamigrene natural product family. The key disconnections in our synthetic approach include sequential enantioselective decarboxylative allylation and ring-closing olefin metathesis to form the all-carbon quaternary stereocenter and spirocyclic core present in all members of this class of compounds. The generality of this strategy is demonstrated by the first total syntheses of elatol and the proposed structure of laurencenone B, as well as the first enantioselective total syntheses of laurencenone C and \u03b1-chamigrene. A brief exploration of the substrate scope of the enantioselective decarboxylative allylation/ring-closing metathesis sequence with fully substituted vinyl chlorides is also presented.",
"doi": "10.1016/j.tet.2010.04.128",
"pmcid": "PMC2925317",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2010-06-26",
"series_number": "26",
"volume": "66",
"issue": "26",
"pages": "4668-4686"
},
{
"id": "authors:q3m5b-fec90",
"collection": "authors",
"collection_id": "q3m5b-fec90",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100527-094834306",
"type": "article",
"title": "NMR Chemical Shifts of Trace Impurities: Common\n Laboratory Solvents, Organics, and Gases in Deuterated\n Solvents Relevant to the Organometallic\n Chemist",
"author": [
{
"family_name": "Fulmer",
"given_name": "Gregory R.",
"clpid": "Fulmer-G-R"
},
{
"family_name": "Miller",
"given_name": "Alexander J. M.",
"clpid": "Miller-A-J-M"
},
{
"family_name": "Sherden",
"given_name": "Nathaniel H.",
"clpid": "Sherden-N-H"
},
{
"family_name": "Gottlieb",
"given_name": "Hugo E.",
"clpid": "Gottlieb-H-E"
},
{
"family_name": "Nudelman",
"given_name": "Abraham",
"clpid": "Nudelman-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Bercaw",
"given_name": "John E.",
"clpid": "Bercaw-J-E"
},
{
"family_name": "Goldberg",
"given_name": "Karen I.",
"clpid": "Goldberg-K-I"
}
],
"abstract": "Tables of ^1H and ^(13)C NMR chemical shifts have been compiled for common organic compounds often used as reagents or found as products or contaminants in deuterated organic solvents. Building upon the work of Gottlieb, Kotlyar, and Nudelman in the Journal of Organic Chemistry, signals for common impurities are now reported in additional NMR solvents (tetrahydrofuran-d_8, toluene-d_8, dichloromethane-d_2, chlorobenzene-d_5, and 2,2,2-trifluoroethanol-d_3) which are frequently used in organometallic laboratories. Chemical shifts for other organics which are often used as reagents or internal standards or are found as products in organometallic chemistry are also reported for all the listed solvents.",
"doi": "10.1021/om100106e",
"issn": "0276-7333",
"publisher": "American Chemical Society",
"publication": "Organometallics",
"publication_date": "2010-05-10",
"series_number": "9",
"volume": "29",
"issue": "9",
"pages": "2176-2179"
},
{
"id": "authors:wgssz-6zy72",
"collection": "authors",
"collection_id": "wgssz-6zy72",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100413-105259618",
"type": "article",
"title": "Aryne Acyl-Alkylation in the General and Convergent Synthesis of Benzannulated Macrolactone Natural Products: An Enantioselective Synthesis of (\u2212)-Curvularin",
"author": [
{
"family_name": "Tadross",
"given_name": "Pamela M.",
"clpid": "Tadross-P-M"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A general approach for the synthesis of benzannulated macrolactone natural products utilizing an aryne acyl-alkylation reaction is described. Toward this end, the total syntheses of the natural products (\u2212)-curvularin, curvulin, and (\u2212)-diplodialide C are reported. Furthermore, the aryne insertion technology has enabled the rapid conversion of simple diplodialide natural products to curvularin, thereby connecting these two biosynthetically distinct classes of compounds via synthetic methods.",
"doi": "10.1021/ol100335y",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2010-04-02",
"series_number": "7",
"volume": "12",
"issue": "7",
"pages": "1612-1614"
},
{
"id": "authors:w1cw1-0bz75",
"collection": "authors",
"collection_id": "w1cw1-0bz75",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100405-115154177",
"type": "article",
"title": "Regioselective Reactions of Highly Substituted Arynes",
"author": [
{
"family_name": "Tadross",
"given_name": "Pamela M.",
"clpid": "Tadross-P-M"
},
{
"family_name": "Gilmore",
"given_name": "Christopher D.",
"clpid": "Gilmore-C-D"
},
{
"family_name": "Bugga",
"given_name": "Pradeep",
"clpid": "Bugga-P"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The fully regioselective reactivity of four new highly substituted silyl aryl triflate aryne precursors in aryne acyl-alkylation, acyl-alkylation/condensation, and heteroannulation reactions is reported. The application of these more complex arynes provides access to diverse natural product scaffolds and obviates late-stage functionalization of aromatic rings.",
"doi": "10.1021/ol1000796",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2010-03-19",
"series_number": "6",
"volume": "12",
"issue": "6",
"pages": "1224-1227"
},
{
"id": "authors:r3egp-pbk04",
"collection": "authors",
"collection_id": "r3egp-pbk04",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100305-152223080",
"type": "article",
"title": "A palladium-catalysed enolate alkylation cascade for the formation of adjacent quaternary and tertiary stereocentres",
"author": [
{
"family_name": "Streuff",
"given_name": "Jan",
"clpid": "Streuff-J"
},
{
"family_name": "White",
"given_name": "David E.",
"clpid": "White-D-E"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The catalytic enantioselective synthesis of densely functionalized organic molecules that contain all-carbon quaternary stereocentres is a challenge to modern chemical methodology. The catalytically controlled, asymmetric \u03b1-alkylation of ketones represents another difficult task and is of major interest to our and other research groups. We report here a palladium-catalysed enantioselective process that addresses both problems simultaneously and allows the installation of vicinal all-carbon quaternary and tertiary stereocentres at the \u03b1-carbon of a ketone in a single step. This multiple bond-forming process is carried out on readily available \u03b2-ketoester starting materials and proceeds by conjugate addition of a palladium enolate, generated in situ, to activated Michael acceptors. As a result, the CO_2 moiety of the substrate is displaced by a C\u2013C fragment in an asymmetric cut-and-paste reaction with high yield, diastereomeric ratio and enantiomeric excess.",
"doi": "10.1038/nchem.518",
"pmcid": "PMC2917108",
"issn": "1755-4330",
"publisher": "Nature Publishing Group",
"publication": "Nature Chemistry",
"publication_date": "2010-03",
"series_number": "3",
"volume": "2",
"issue": "3",
"pages": "192-196"
},
{
"id": "authors:w6q47-3w802",
"collection": "authors",
"collection_id": "w6q47-3w802",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100218-140616247",
"type": "article",
"title": "The Palladium-Catalyzed Aerobic Kinetic Resolution of Secondary Alcohols: Reaction Development, Scope, and Applications",
"author": [
{
"family_name": "Ebner",
"given_name": "David C.",
"clpid": "Ebner-D-C"
},
{
"family_name": "Bagdanoff",
"given_name": "Jeffrey T.",
"clpid": "Bagdanoff-J-T"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "McFadden",
"given_name": "Ryan M.",
"clpid": "McFadden-R-M"
},
{
"family_name": "Caspi",
"given_name": "Daniel D.",
"clpid": "Caspi-D-D"
},
{
"family_name": "Trend",
"given_name": "Raissa M.",
"clpid": "Trend-R-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first palladium-catalyzed enantioselective oxidation of secondary alcohols has been developed, utilizing the readily available diamine (-)-sparteine as a chiral ligand and molecular oxygen as the stoichiometric oxidant. Mechanistic insights regarding the role of the base and hydrogen-bond donors have resulted in several improvements to the original system. Namely, addition of cesium carbonate and tert-butyl alcohol greatly enhances reaction rates, promoting rapid resolutions. The use of chloroform as solvent allows the use of ambient air as the terminal oxidant at 23 \u00b0C, resulting in enhanced catalyst selectivity. These improved reaction conditions have permitted the successful kinetic resolution of benzylic, allylic, and cyclopropyl secondary alcohols to high enantiomeric excess with good-to-excellent selectivity factors. This catalyst system has also been applied to the desymmetrization of meso-diols, providing high yields of enantioenriched hydroxyketones.",
"doi": "10.1002/chem.200902172",
"pmcid": "PMC2862982",
"issn": "0947-6539",
"publisher": "John Wiley & Sons",
"publication": "Chemistry: a European Journal",
"publication_date": "2009-12-07",
"series_number": "47",
"volume": "15",
"issue": "47",
"pages": "12978-12992"
},
{
"id": "authors:q1wch-n4x83",
"collection": "authors",
"collection_id": "q1wch-n4x83",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091214-081131773",
"type": "article",
"title": "Expedient synthesis of 3-hydroxyisoquinolines and 2-hydroxy-1,4-naphthoquinones via one-pot aryne acyl-alkylation/condensation",
"author": [
{
"family_name": "Allan",
"given_name": "Kevin M.",
"orcid": "0000-0002-7750-3621",
"clpid": "Allan-K-M"
},
{
"family_name": "Hong",
"given_name": "Boram D.",
"clpid": "Hong-B-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A convenient method is disclosed for the synthesis of both 3-hydroxyisoquinolines and 2-hydroxy-1,4-naphthoquinones from b-ketoesters using a one-pot aryne acyl-alkylation/condensation procedure. When performed in conjunction with a one-step method for the synthesis of the b-ketoester substrates, this method provides a new route to these polyaromatic structures in only two steps from commercially available carboxylic acid starting materials. The utility of this approach is demonstrated\nin the synthesis of the atropisomeric P,N-ligand, QUINAP.",
"doi": "10.1039/b913336d",
"issn": "1477-0520",
"publisher": "Royal Society of Chemistry",
"publication": "Organic and Biomolecular Chemistry",
"publication_date": "2009-12-07",
"series_number": "23",
"volume": "7",
"issue": "23",
"pages": "4960-4964"
},
{
"id": "authors:8a6kg-r4b87",
"collection": "authors",
"collection_id": "8a6kg-r4b87",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091002-090709845",
"type": "article",
"title": "Catalytic Enantioselective Stereoablative Alkylation of 3-Halooxindoles: Facile Access to Oxindoles with C3 All-Carbon Quaternary Stereocenters",
"author": [
{
"family_name": "Ma",
"given_name": "Sandy",
"clpid": "Ma-Sandy"
},
{
"family_name": "Han",
"given_name": "Xiaoqing",
"clpid": "Han-Xiaoqing"
},
{
"family_name": "Krishnan",
"given_name": "Shyam",
"clpid": "Krishnan-Shyam"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "From 2 to 1! Racemic tertiary halooxindoles proceed to enantioenriched oxindoles bearing all-carbon quaternary stereocenters as a result of a catalytic enantioselective stereoablative process (see scheme). The application of this procedure allows for the rapid asymmetric construction of biologically significant alkaloid core motifs.",
"doi": "10.1002/anie.200902943",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2009-09-09",
"series_number": "1",
"volume": "48",
"issue": "1",
"pages": "1-6"
},
{
"id": "authors:nyyp3-12w45",
"collection": "authors",
"collection_id": "nyyp3-12w45",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091012-124240065",
"type": "article",
"title": "Unusual Allylpalladium Carboxylate Complexes: Identification of the Resting State of Catalytic Enantioselective Decarboxylative Allylic Alkylation Reactions of Ketones",
"author": [
{
"family_name": "Sherden",
"given_name": "Nathaniel H.",
"clpid": "Sherden-N-H"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Virgil",
"given_name": "Scott C.",
"orcid": "0000-0001-8586-5641",
"clpid": "Virgil-S-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Palladium pop rocks: Hold on to your CO2! Enantioselective palladium-catalyzed decarboxylative alkylation of ketone enolates proceeds via 1-\u03c3-allyl palladium-carboxylate complexes, such as 1 (Pd yellow, O red, N blue, P purple), by slow loss of CO_2. Reminiscent of pop rock candy, impure samples of 1 expel a gas (presumably CO_2) in the solid state and effervesce in solution.",
"doi": "10.1002/anie.200902575",
"pmcid": "PMC2880474",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2009-09-01",
"series_number": "37",
"volume": "48",
"issue": "37",
"pages": "6840-6843"
},
{
"id": "authors:z347m-5c422",
"collection": "authors",
"collection_id": "z347m-5c422",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090817-150141765",
"type": "article",
"title": "An efficient synthesis of the carbocyclic core of zoanthenol",
"author": [
{
"family_name": "Stockdill",
"given_name": "Jennifer L.",
"clpid": "Stockdill-J-L"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "McClory",
"given_name": "Andrew",
"clpid": "McClory-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A concise strategy for the synthesis of the carbocyclic portion of zoanthenol is disclosed. The key step involves a 6-endo radical-mediated conjugate addition that constructs the quaternary stereocenter at C(12) and closes the B ring in a stereoselective manner. The synthesis of the C-ring fragment uses an enantioselective desymmetrization to simultaneously establish the absolute stereochemistry of two vicinal quaternary stereocenters. In only 17 steps from known compounds, the route affords an ABC ring system containing all three quaternary stereocenters and appropriate functionality to complete the synthesis of zoanthenol.",
"doi": "10.1016/j.tet.2009.05.023",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2009-08-15",
"series_number": "33",
"volume": "65",
"issue": "33",
"pages": "6571-6575"
},
{
"id": "authors:51rpb-mt493",
"collection": "authors",
"collection_id": "51rpb-mt493",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090828-231033230",
"type": "article",
"title": "Enantioselective protonation",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Hong",
"given_name": "Allen Y.",
"clpid": "Hong-Allen-Y"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Enantioselective protonation is a common process in biosynthetic sequences. The decarboxylase and esterase enzymes that effect this valuable transformation are able to control both the steric environment around the proton acceptor (typically an enolate) and the proton donor (typically a thiol). Recently, several chemical methods for achieving enantioselective protonation have been developed by exploiting various means of enantiocontrol in different mechanisms. These laboratory transformations have proved useful for the preparation of a number of valuable organic compounds. Here, we review recent reports of enantioselective protonations, classifying them according to mechanism, and discuss how a deeper understanding of the processes can lead to improved methods for effecting this most fundamental method of obtaining enantiopure compounds.",
"doi": "10.1038/nchem.297",
"pmcid": "PMC2860147",
"issn": "1755-4330",
"publisher": "Nature Publishing Group",
"publication": "Nature Chemistry",
"publication_date": "2009-08",
"series_number": "5",
"volume": "1",
"issue": "5",
"pages": "359-369"
},
{
"id": "authors:3c0q4-z8x15",
"collection": "authors",
"collection_id": "3c0q4-z8x15",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090909-132757912",
"type": "article",
"title": "Unexpected decarbonylation during an acid-mediated cyclization to access the carbocyclic core of zoanthenol",
"author": [
{
"family_name": "Stockdill",
"given_name": "Jennifer L.",
"clpid": "Stockdill-J-L"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An unusual loss of CO was observed during a key cyclization event in efforts toward the total synthesis of zoanthenol. The synthesis of the cyclization precursor and a proposed mechanism for decarbonylation are detailed.",
"doi": "10.1016/j.tetlet.2009.01.121",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2009-07-01",
"series_number": "26",
"volume": "50",
"issue": "26",
"pages": "3182-3184"
},
{
"id": "authors:069z9-1zh80",
"collection": "authors",
"collection_id": "069z9-1zh80",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090728-105816044",
"type": "article",
"title": "Synthetic efforts toward cyathane diterpenoid natural products",
"author": [
{
"family_name": "Enquist",
"given_name": "John A.",
"clpid": "Enquist-J-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An overview of synthetic efforts toward cyathane diterpenoid natural products from the year 2000 to present is provided. The emphasis of this review is the various ring-constructing and stereoforming strategies employed in these synthetic routes.",
"doi": "10.1039/b811227b",
"pmcid": "PMC2683363",
"issn": "0265-0568",
"publisher": "Royal Society of Chemistry",
"publication": "Natural Product Reports",
"publication_date": "2009-05",
"series_number": "5",
"volume": "26",
"issue": "5",
"pages": "661-680"
},
{
"id": "authors:f5efz-det95",
"collection": "authors",
"collection_id": "f5efz-det95",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090914-100459696",
"type": "article",
"title": "Progress toward the synthesis of the transtaganolide/basiliolide natural products: an Ireland\u2013Claisen approach",
"author": [
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Efforts toward the synthesis of the transtaganolide natural product family are described. A highly efficient Ireland\u2013Claisen/Diels\u2013Alder approach has been developed, which rapidly constructs the highly oxygenated and stereochemically rich core of these natural products.",
"doi": "10.1016/j.tetlet.2009.01.108",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2009-04-15",
"series_number": "15",
"volume": "50",
"issue": "15",
"pages": "1699-1701"
},
{
"id": "authors:6ekp7-s4m41",
"collection": "authors",
"collection_id": "6ekp7-s4m41",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090630-151621799",
"type": "article",
"title": "Side chain chemistry mediates backbone fragmentation in hydrogen deficient peptide radicals",
"author": [
{
"family_name": "Sun",
"given_name": "Qingyu",
"clpid": "Sun-Qingyu"
},
{
"family_name": "Nelson",
"given_name": "Hosea",
"clpid": "Nelson-H"
},
{
"family_name": "Ly",
"given_name": "Tony",
"clpid": "Ly-Tony"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Julian",
"given_name": "Ryan R.",
"orcid": "0000-0003-1580-8355",
"clpid": "Julian-R-R"
}
],
"abstract": "A crown ether based, photolabile radical precursor which forms noncovalent complexes with peptides has been prepared. The peptide/precursor complexes can be electrosprayed, isolated in an ion trap, and then subjected to laser photolysis and collision induced dissociation to generate hydrogen deficient peptide radicals. It is demonstrated that these peptide radicals behave very differently from the hydrogen rich peptide radicals generated by electron capture methods. In fact, it is shown that side chain chemistry dictates both the occurrence and relative abundance of backbone fragments that are observed. Fragmentation at aromatic residues occurs preferentially over most other amino acids. The origin of this selectivity relates to the mechanism by which backbone dissociation is initiated. The first step is abstraction of a \u03b2-hydrogen from the side chain, followed by beta-elimination to yield primarily a-type fragment ions. Calculations reveal that those side chains which can easily lose a \u03b2-hydrogen correlate well with experimentally favored sites for backbone fragmentation. In addition, radical mediated side chain losses from the parent peptide are frequently observed. Eleven amino acids exhibit unique mass losses from side chains which positively identify that particular amino acid as part of the parent peptide. Therefore, side chain losses allow one to unambiguously narrow the possible sequences for a parent peptide, which when combined with predictable backbone fragmentation should lead to greatly increased confidence in peptide identification.",
"doi": "10.1021/pr800592t",
"issn": "1535-3893",
"publisher": "American Chemical Society",
"publication": "Journal of Proteome Research",
"publication_date": "2009-02",
"series_number": "2",
"volume": "8",
"issue": "2",
"pages": "958-966"
},
{
"id": "authors:knp18-zkv25",
"collection": "authors",
"collection_id": "knp18-zkv25",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190903-130240760",
"type": "article",
"title": "The direct acyl-alkylation of arynes. Preparation of methyl 2-(2-acetylphenyl)acetate",
"author": [
{
"family_name": "Ebner",
"given_name": "David C.",
"clpid": "Ebner-D-C"
},
{
"family_name": "Tambar",
"given_name": "Uttam K.",
"clpid": "Tambar-U-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "[no abstract]",
"doi": "10.15227/orgsyn.086.0161",
"issn": "2333-3553",
"publisher": "Organic Syntheses, Inc.",
"publication": "Organic Syntheses",
"publication_date": "2009-01-16",
"volume": "86",
"pages": "161-171"
},
{
"id": "authors:g7008-ta722",
"collection": "authors",
"collection_id": "g7008-ta722",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:LEVol09",
"type": "article",
"title": "Catalytic enantioselective approach to the eudesmane sesquiterpenoids: total synthesis of (+)-carissone",
"author": [
{
"family_name": "Levine",
"given_name": "Samantha R.",
"clpid": "Levine-S-R"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A catalytic enantioselective approach to the eudesmane sesquiterpenoids is reported. The strategic use of a palladium-catalyzed enantioselective alkylation of vinylogous ester substrates forged the C(10) all-carbon quaternary center. This key transformation enabled a diastereoselective olefin hydrogenation to create the syn stereochemistry at C(7). The devised synthetic strategy allowed for the preparation of the antibacterial agent (+)-carissone and a formal synthesis of the P/Q-type calcium channel blocker (-)-\u03b1-eudesmol.",
"doi": "10.1021/ol802409h",
"pmcid": "PMC2724392",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2009-01-15",
"series_number": "2",
"volume": "11",
"issue": "2",
"pages": "289-292"
},
{
"id": "authors:qcjq4-wbg50",
"collection": "authors",
"collection_id": "qcjq4-wbg50",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:PETol09",
"type": "article",
"title": "Enantioselective Total Synthesis of (+)-Cassiol",
"author": [
{
"family_name": "Petrova",
"given_name": "Krastina V.",
"clpid": "Petrova-K-V"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantioselective total synthesis of (+)-cassiol is reported. The complex derived from Pd-2(pmdba)(3) and enantiopure t-BuPHOX ligand catalyzes enantioconvergent decarboxylative alkylation to generate the quaternary carbon stereocenter at an early stage. The overall synthetic strategy involves a convergent late-stage coupling of two fragments. The synthesis features a longest linear sequence of eight steps.",
"doi": "10.1021/ol802410t",
"pmcid": "PMC2707596",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2009-01-15",
"series_number": "2",
"volume": "11",
"issue": "2",
"pages": "293-295"
},
{
"id": "authors:5trbm-03367",
"collection": "authors",
"collection_id": "5trbm-03367",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141223-105727889",
"type": "article",
"title": "Preparation of (S)-tert-ButylPHOX (Oxazole, 4-(1,1-dimethylethyl)-2-[2-(diphenylphosphino)phenyl]-4,5-dihydro- (4S)-)",
"author": [
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Schumacher",
"given_name": "Andreas",
"clpid": "Schumacher-A"
}
],
"abstract": "[No abstract]",
"doi": "10.15227/orgsyn.086.0181",
"pmcid": "PMC2805096",
"issn": "0078-6209",
"publisher": "Wiley",
"publication": "Organic Syntheses",
"publication_date": "2009",
"volume": "86",
"pages": "181-193"
},
{
"id": "authors:4cf7e-gf483",
"collection": "authors",
"collection_id": "4cf7e-gf483",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150106-134315572",
"type": "article",
"title": "Preparation of (S)-2-Allyl-2-methylcyclohexanone (Cyclohexanone, 2-methyl-2-(2-propen-1-yl)-, (2S)-)",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "[No abstract]",
"doi": "10.15227/orgsyn.086.0194",
"pmcid": "PMC3011275",
"issn": "0078-6209",
"publisher": "Wiley",
"publication": "Organic Syntheses",
"publication_date": "2009",
"volume": "86",
"pages": "194-211"
},
{
"id": "authors:zk09j-3dv78",
"collection": "authors",
"collection_id": "zk09j-3dv78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090728-134418790",
"type": "article",
"title": "Structural features and reactivity of (sparteine)PdCl_2: a model for selectivity in the oxidative kinetic resolution of secondary alcohols",
"author": [
{
"family_name": "Trend",
"given_name": "Raissa M.",
"clpid": "Trend-R-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The chiral ligand (\u2212)-sparteine and PdCl_2 catalyze the enantioselective oxidation of secondary alcohols to ketones and thus effect a kinetic resolution. The structural features of sparteine that led to the selectivity observed in the reaction were not clear. Substitution experiments with pyridine derivatives and structural studies of the complexes generated were carried out on (sparteine)PdCl2 and indicated that the C1 symmetry of (\u2212)-sparteine is essential to the location of substitution at the metal center. Palladium alkoxides were synthesized from secondary alcohols that are relevant steric models for the kinetic resolution. The solid-state structures of the alkoxides also confirmed the results from the pyridine derivative substitution studies. A model for enantioinduction was developed with C1 symmetry and Cl\u2212 as key features. Further studies of the diastereomers of (\u2212)-sparteine, (\u2212)-\u03b1-iso- and (+)-\u03b2-isosparteine, in the kinetic resolution showed that these C_2-symmetric counterparts are inferior ligands in this stereoablative reaction",
"doi": "10.1021/ja804955e",
"pmcid": "PMC2649720",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2008-11-26",
"series_number": "47",
"volume": "130",
"issue": "47",
"pages": "15957-15966"
},
{
"id": "authors:w6mkw-pyb91",
"collection": "authors",
"collection_id": "w6mkw-pyb91",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090804-102608108",
"type": "article",
"title": "A concise total synthesis of (\u2212)-quinocarcin via aryne annulation",
"author": [
{
"family_name": "Allan",
"given_name": "Kevin M.",
"orcid": "0000-0002-7750-3621",
"clpid": "Allan-K-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Described in this report is a rapid asymmetric total synthesis of the tetrahydroisoquinoline antitumor antibiotic (\u2212)-quinocarcin. The sequence employs a mild fluoride-induced aryne annulation developed in our laboratories to build a key isoquinoline-containing intermediate comprising the entire carbon scaffold of the natural product. This intermediate is advanced through six additional steps to the target alkaloid, providing the shortest synthetic route to (\u2212)-quinocarcin reported to date.",
"doi": "10.1021/ja808112y",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2008-11-26",
"series_number": "51",
"volume": "130",
"issue": "51",
"pages": "17270-17271"
},
{
"id": "authors:zhatv-x6064",
"collection": "authors",
"collection_id": "zhatv-x6064",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:KRIjacs08",
"type": "article",
"title": "Pd-catalyzed enantioselective aerobic oxidation of secondary alcohols: Applications to the total synthesis of alkaloids",
"author": [
{
"family_name": "Krishnan",
"given_name": "Shyam",
"clpid": "Krishnan-Shyam"
},
{
"family_name": "Bagdanoff",
"given_name": "Jeffrey T.",
"clpid": "Bagdanoff-J-T"
},
{
"family_name": "Ebner",
"given_name": "David C.",
"clpid": "Ebner-D-C"
},
{
"family_name": "Ramtohul",
"given_name": "Yeeman K.",
"clpid": "Ramtohul-Y-K"
},
{
"family_name": "Tambar",
"given_name": "Uttam K.",
"clpid": "Tambar-U-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Enantioselective syntheses of the alkaloids (-)-aurantioclavine, (+)-amurensinine, (-)-lobeline, and (-)- and (+)-sedamine are described. The syntheses demonstrate the effectiveness of the Pd-catalyzed asymmetric oxidation of secondary alcohols in diverse contexts and the ability of this methodology to set the absolute configuration of multiple stereocenters in a single operation. The utility of an aryne C-C insertion reaction in accessing complex polycyclic frameworks is also described.",
"doi": "10.1021/ja804738b",
"pmcid": "PMC2574996",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2008-10-15",
"series_number": "41",
"volume": "130",
"issue": "41",
"pages": "13745-13754"
},
{
"id": "authors:gx20s-p9m61",
"collection": "authors",
"collection_id": "gx20s-p9m61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:MOHnat08",
"type": "article",
"title": "Natural products as inspiration for the development of asymmetric catalysis",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Krout",
"given_name": "Michael R.",
"orcid": "0000-0002-0539-6986",
"clpid": "Krout-M-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Biologically active natural products often contain particularly challenging structural features and\nfunctionalities in terms of synthesis. Perhaps the greatest difficulties are those caused by issues of\nstereochemistry. A useful strategy for synthesizing such molecules is to devise methods of bond formation\nthat provide opportunities for using enantioselective catalysis. In using this tactic, the desire for a particular\ntarget structure ultimately drives the development of catalytic methods. New enantioselective catalytic\nmethods contribute to a greater fundamental understanding of how bonds can be constructed and lead to valuable synthetic technologies that are useful for a variety of applications.",
"doi": "10.1038/nature07370",
"pmcid": "PMC2562237",
"issn": "0028-0836",
"publisher": "Nature Publishing Group",
"publication": "Nature",
"publication_date": "2008-09-18",
"series_number": "7211",
"volume": "455",
"issue": "7211",
"pages": "323-332"
},
{
"id": "authors:3v7r6-avz40",
"collection": "authors",
"collection_id": "3v7r6-avz40",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-154336630",
"type": "article",
"title": "Catalytic Enantioselective Alkylation of Substituted Dioxanone Enol Ethers: Ready Access to C(\u03b1)-Tetrasubstituted Hydroxyketones, Acids, and Esters",
"author": [
{
"family_name": "Seto",
"given_name": "Masaki",
"clpid": "Seto-Masaki"
},
{
"family_name": "Roizen",
"given_name": "Jennifer L.",
"orcid": "0000-0002-6053-5512",
"clpid": "Roizen-J-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Adaptive Alkylation: Palladium-catalyzed asymmetric alkylation enables access to fully substituted enantioenriched oxygenated stereocenters, which can be transformed easily to \u03b1-hydroxyketones, esters, and acids, providing a catalytic, enantioselective synthesis for natural products.",
"doi": "10.1002/anie.200801424",
"pmcid": "PMC2762748",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2008-08-25",
"series_number": "36",
"volume": "47",
"issue": "36",
"pages": "6873-6876"
},
{
"id": "authors:hqgfj-akn38",
"collection": "authors",
"collection_id": "hqgfj-akn38",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-152617371",
"type": "article",
"title": "Palladium-Catalyzed Enantioselective Oxidation of Chiral Secondary Alcohols: Access to Both Enantiomeric Series",
"author": [
{
"family_name": "Ebner",
"given_name": "David C.",
"clpid": "Ebner-D-C"
},
{
"family_name": "Trend",
"given_name": "Raissa M.",
"clpid": "Trend-R-M"
},
{
"family_name": "Genet",
"given_name": "C\u00e9dric",
"clpid": "Genet-C"
},
{
"family_name": "McGrath",
"given_name": "Matthew J.",
"clpid": "McGrath-M-J"
},
{
"family_name": "O'Brien",
"given_name": "Peter",
"clpid": "O'Brien-Peter"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Rapid resolution: A new catalyst system for the oxidative kinetic resolution of secondary alcohols leads to dramatic rate increases. This system allows the use of a diamine to provide access to either enantiomer of a range of alcohols with good selectivity factors (see scheme). This method has been applied to the formal total synthesis of (\u2212)-amurensinine.",
"doi": "10.1002/anie.200801865",
"pmcid": "PMC2790069",
"issn": "14337851",
"publisher": "Angewandte Chemie International Edition",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2008-08-11",
"series_number": "34",
"volume": "47",
"issue": "34",
"pages": "6367-6370"
},
{
"id": "authors:dpz26-mnh15",
"collection": "authors",
"collection_id": "dpz26-mnh15",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-150759253",
"type": "article",
"title": "The total synthesis of (-)-cyanthiwigin F by means of double catalytic enantioselective alkylation",
"author": [
{
"family_name": "Enquist",
"given_name": "John A., Jr.",
"clpid": "Enquist-J-A-Jr"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Double catalytic enantioselective transformations are powerful synthetic methods that can facilitate the construction of stereochemically complex molecules in a single operation. In addition to generating two or more stereocentres in a single reaction, multiple asymmetric reactions also impart increased enantiomeric excess to the final product in comparison with the analogous single transformation. Furthermore, multiple asymmetric operations have the potential to independently construct several stereocentres at remote points within the same molecular scaffold, rather than relying on pre-existing chiral centres that are proximal to the reactive site. Despite the inherent benefits of multiple catalytic enantioselective reactions, their application to natural product total synthesis remains largely underutilized. Here we report the use of a double stereoablative enantioselective alkylation reaction in a concise synthesis of the marine diterpenoid (-)-cyanthiwigin F (ref. 8). By employing a technique for independent, selective formation of two stereocentres in a single stereoconvergent operation, we demonstrate that a complicated mixture of racemic and meso diastereomers may be smoothly converted to a synthetically useful intermediate with exceptional enantiomeric excess. The stereochemical information generated by means of this catalytic transformation facilitates the easy and rapid completion of the total synthesis of this marine natural product.",
"doi": "10.1038/nature07046",
"pmcid": "PMC2474750",
"issn": "0028-0836",
"publisher": "Nature Publishing Group",
"publication": "Nature",
"publication_date": "2008-06-26",
"series_number": "7199",
"volume": "453",
"issue": "7199",
"pages": "1228-1231"
},
{
"id": "authors:b2qhg-zrz39",
"collection": "authors",
"collection_id": "b2qhg-zrz39",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161128-075820774",
"type": "article",
"title": "C\u2013H bond functionalizations with palladium(II): intramolecular oxidative annulations of arenes",
"author": [
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Oxidative annulations for the synthesis of carbocycles were developed using a catalytic palladium(II) system. Indoles with pendant olefin tethers were oxidatively cyclized to form annulated products. Electron-rich aromatic systems were also investigated, culminating in the synthesis of benzofurans and dihydrobenzofurans by a similar protocol. These reactions were demonstrated to proceed by an initial C\u2013H bond functionalization event, followed by olefin insertion and \u03b2-hydride elimination.",
"doi": "10.1016/j.tet.2008.01.052",
"pmcid": "PMC2441596",
"issn": "0040-4020",
"publisher": "Elsevier",
"publication": "Tetrahedron",
"publication_date": "2008-06-23",
"series_number": "26",
"volume": "64",
"issue": "26",
"pages": "5987-6001"
},
{
"id": "authors:52ge1-1nq44",
"collection": "authors",
"collection_id": "52ge1-1nq44",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170221-162726154",
"type": "article",
"title": "Homogeneous Pd-Catalyzed Enantioselective Decarboxylative Protonation",
"author": [
{
"family_name": "Marinescu",
"given_name": "Smaranda C.",
"orcid": "0000-0003-2106-8971",
"clpid": "Marinescu-S-C"
},
{
"family_name": "Nishimata",
"given_name": "Toyoki",
"clpid": "Nishimata-Toyoki"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "General homogeneous conditions for the palladium-catalyzed synthesis of carbonyl compounds with tertiary carbon stereocenters at the \u03b1-position are reported. The highly reactive catalyst tolerates a variety of substrate substitution and functionality, and generates enantioenriched cyclic ketones from racemic allyl \u03b2-ketoester starting materials.",
"doi": "10.1021/ol702821j",
"pmcid": "PMC2966305",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2008-03-20",
"series_number": "6",
"volume": "10",
"issue": "6",
"pages": "1039-1042"
},
{
"id": "authors:3mape-yvy19",
"collection": "authors",
"collection_id": "3mape-yvy19",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-151808188",
"type": "article",
"title": "The Biology and Chemistry of the Zoanthamine Alkaloids",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stockdill",
"given_name": "Jennifer L.",
"clpid": "Stockdill-J-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Marine natural products have long played an important role in natural products chemistry and drug discovery. Mirroring the rich variety and complicated interactions of the marine environment, the substances isolated from sea creatures tend to be incredibly diverse in both molecular structure and biological activity. The natural products isolated from the polyps of marine zoanthids are no exception. The zoanthamine alkaloids, the first of which were isolated over 20 years ago, are of particular interest to the synthetic community because they feature a novel structural framework and exhibit a broad range of biological activities. In this Review, we summarize the major contributions to understanding the zoanthamine natural products with regard to their isolation and structure determination, as well as studies on their biological activity and total synthesis.",
"doi": "10.1002/anie.200703172",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2008-03-14",
"series_number": "13",
"volume": "47",
"issue": "13",
"pages": "2365-2386"
},
{
"id": "authors:9f3y0-af469",
"collection": "authors",
"collection_id": "9f3y0-af469",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170223-153451419",
"type": "article",
"title": "Orthogonal Synthesis of Indolines and Isoquinolines via Aryne Annulation",
"author": [
{
"family_name": "Gilmore",
"given_name": "Christopher D.",
"clpid": "Gilmore-C-D"
},
{
"family_name": "Allan",
"given_name": "Kevin M.",
"orcid": "0000-0002-7750-3621",
"clpid": "Allan-K-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Described in this report is the development of two unique methodologies exploiting the reactivity of arynes. Reaction of N-carbamoyl-functionalized enamine derivatives with benzyne affords substituted indolines. An orthogonal reactivity is uncovered when related enamine derivatives are modified as amides, such that isoquinolines are formed as the product of condensation with benzyne. This latter transformation is applied to a concise total synthesis of the opiate alkaloid papaverine.",
"doi": "10.1021/ja0780582",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2008-02-06",
"series_number": "5",
"volume": "130",
"issue": "5",
"pages": "1558-1559"
},
{
"id": "authors:adksr-ttw02",
"collection": "authors",
"collection_id": "adksr-ttw02",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-082042531",
"type": "article",
"title": "The Catalytic Asymmetric Total Synthesis of Elatol",
"author": [
{
"family_name": "White",
"given_name": "David E.",
"clpid": "White-D-E"
},
{
"family_name": "Stewart",
"given_name": "Ian C.",
"clpid": "Stewart-I-C"
},
{
"family_name": "Grubbs",
"given_name": "Robert H.",
"orcid": "0000-0002-0057-7817",
"clpid": "Grubbs-R-H"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Described in this report is the first total synthesis of elatol, a halogenated sesquiterpene in the chamigrene natural product family. The key disconnections in our synthetic approach include an enantioselective decarboxylative allylation to form the all-carbon quaternary stereocenter and a ring-closing olefin metathesis to concomitantly form the spirocyclic core as well as the fully substituted chlorinated olefin. This strategy represents a general platform for accessing the chamigrene natural product family, as demonstrated by the synthesis of (+)-laurencenone B as an intermediate in our route.",
"doi": "10.1021/ja710294k",
"pmcid": "PMC2533138",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2008-01-23",
"series_number": "3",
"volume": "130",
"issue": "3",
"pages": "810-811"
},
{
"id": "authors:m0ncb-ykz14",
"collection": "authors",
"collection_id": "m0ncb-ykz14",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-094911569",
"type": "article",
"title": "Progress toward the Synthesis of the Basiliolides and Transtaganolides: An Intramolecular Pyrone Diels\u2212Alder Entry into a Novel Class of Natural Products",
"author": [
{
"family_name": "Nelson",
"given_name": "Hosea M.",
"orcid": "0000-0002-4666-2793",
"clpid": "Nelson-H-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Efforts directed toward the synthesis of a basiliolide/transtaganolide model system are disclosed. A highly endo-selective intramolecular pyrone Diels\u2212Alder (IMPDA) cycloaddition rapidly constructs the tricyclic core of the basiliolides and transtaganolides.",
"doi": "10.1021/ol702501s",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2008-01-03",
"series_number": "1",
"volume": "10",
"issue": "1",
"pages": "25-28"
},
{
"id": "authors:vpg4e-da793",
"collection": "authors",
"collection_id": "vpg4e-da793",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-130857215",
"type": "article",
"title": "Enantioselective Tsuji Allylations",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The family of allylation reactions developed by Tsuji in the 1980s are capable of generating tertiary and quaternary carbon stereocenters from several synthetic precursors. Despite the utility of these transformations, they have seen little use in the synthesis of natural products. Recently, the power of these reactions was significantly enhanced by the development of enantioselective versions of these transformations. Applications of these methods to the enantioselective syntheses of natural products and pharmaceutical compounds highlight the importance of these developments.",
"doi": "10.1002/asia.200700183",
"pmcid": "PMC2967289",
"issn": "1861-4728",
"publisher": "Wiley",
"publication": "Chemistry \u2013 An Asian Journal",
"publication_date": "2007-12-03",
"series_number": "12",
"volume": "2",
"issue": "12",
"pages": "1476-1491"
},
{
"id": "authors:q13cb-p9f76",
"collection": "authors",
"collection_id": "q13cb-p9f76",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170223-071515692",
"type": "article",
"title": "Catalytic enantioselective stereoablative reactions: an unexploited approach to enantioselective catalysis",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Ebner",
"given_name": "David C.",
"clpid": "Ebner-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Approaches to the preparation of enantioenriched materials via catalytic methods that destroy stereogenic elements of a molecule are discussed. Although these processes often decrease overall molecular complexity, there are several notable advantages including material recycling, enantiodivergence and convergence, and increased substrate scope. Examples are accompanied by discussion of the critical design elements required for the success of these methods.",
"doi": "10.1039/B711159M",
"pmcid": "PMC2963431",
"issn": "1477-0520",
"publisher": "Royal Society of Chemistry",
"publication": "Organic and Biomolecular Chemistry",
"publication_date": "2007-11-21",
"series_number": "22",
"volume": "5",
"issue": "22",
"pages": "3571-3576"
},
{
"id": "authors:j28d6-ee609",
"collection": "authors",
"collection_id": "j28d6-ee609",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-080249889",
"type": "article",
"title": "The Inner-Sphere Process in the Enantioselective Tsuji Allylation Reaction with (S)-t-Bu-phosphinooxazoline Ligands",
"author": [
{
"family_name": "Keith",
"given_name": "John A.",
"orcid": "0000-0002-6583-6322",
"clpid": "Keith-J-A"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Ma",
"given_name": "Sandy",
"clpid": "Ma-Sandy"
},
{
"family_name": "Marinescu",
"given_name": "Smaranda C.",
"orcid": "0000-0003-2106-8971",
"clpid": "Marinescu-S-C"
},
{
"family_name": "Oxgaard",
"given_name": "Jonas",
"clpid": "Oxgaard-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
}
],
"abstract": "We propose an inner-sphere mechanism explaining the unique performance of the Tsuji asymmetrical allylation reaction using hard prochiral enolate nucleophiles and non-prochiral allyl groups. Using first principles quantum mechanics (B3LYP density functional theory), we find that the pathway for this reaction involves nucleophilic attack followed by interconversion from a five-coordinate Pd complex to a four-coordinate complex. This intermediate is trapped in a potential well and escapes via reductive elimination that proceeds through a seven-membered transition state to generate the product and a Pd^0 complex. This seven-membered transition state contrasts dramatically from the usual three-centered C\u2212C reductive elimination paradigm generally associated with C\u2212C coupling reactions. This inner-sphere asymmetric allylation pathway involving hard enolates is energetically more favorable than outer-sphere nucleophilic attack, a process understood to occur in asymmetric allylic alkylations with soft enolates.",
"doi": "10.1021/ja070516j",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2007-10-03",
"series_number": "39",
"volume": "129",
"issue": "39",
"pages": "11876-11877"
},
{
"id": "authors:w62we-h5t96",
"collection": "authors",
"collection_id": "w62we-h5t96",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-155814896",
"type": "article",
"title": "Convergency and Divergency as Strategic Elements in Total Synthesis: The Total Synthesis of (\u2212)-Drupacine and the Formal Total Synthesis of (\u00b1)-Cephalotaxine, (\u2212)-Cephalotaxine, and (+)-Cephalotaxine",
"author": [
{
"family_name": "Liu",
"given_name": "Qi",
"clpid": "Liu-Qi"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A concise route toward the syntheses of (\u2212)-drupacine and (+)- and (\u2212)-cephalotaxine has been developed. The syntheses rely on Pd(II)-catalyzed aerobic oxidative heterocyclization chemistry, which was employed to rapidly construct an important spirocyclic amine intermediate. A dynamic \u03b2-elimination/conjugate addition process was strategically applied to complete the first asymmetric total synthesis of (\u2212)-drupacine.",
"doi": "10.1021/jo0710883",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2007-09-14",
"series_number": "19",
"volume": "72",
"issue": "19",
"pages": "7352-7358"
},
{
"id": "authors:0dtv3-r6x09",
"collection": "authors",
"collection_id": "0dtv3-r6x09",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-151224179",
"type": "article",
"title": "A Facile and Modular Synthesis of Phosphinooxazoline Ligands",
"author": [
{
"family_name": "Tani",
"given_name": "Kousuke",
"clpid": "Tani-Kousuke"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "McFadden",
"given_name": "Ryan M.",
"clpid": "McFadden-R-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The copper(I) iodide catalyzed phosphine/aryl halide coupling procedure of Buchwald et al. provides modular, robust, and scaleable access to phosphinooxazoline (PHOX) ligands. The advantages of this method are highlighted by the convenient synthesis of PHOX ligands with varied steric and electronic properties, which would be challenging to synthesize by other protocols.",
"doi": "10.1021/ol070884s",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2007-06-21",
"series_number": "13",
"volume": "9",
"issue": "13",
"pages": "2529-2531"
},
{
"id": "authors:00gj1-wj450",
"collection": "authors",
"collection_id": "00gj1-wj450",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-152142036",
"type": "article",
"title": "Synthesis of the Carbocyclic Core of Zoanthenol: Implementation of an Unusual Acid-Catalyzed Cyclization",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stockdill",
"given_name": "Jennifer L.",
"clpid": "Stockdill-J-L"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A smokin' hot cyclization! When the racemic cyclization precursor is heated in neat trifluoroacetic acid, an unusual Friedel\u2013Crafts-type cyclization forms the carbocyclic core of the marine alkaloid zoanthenol containing two all-carbon-substituted quaternary centers. Catalytic asymmetric alkylation allows entry into an enantioselective route.",
"doi": "10.1002/anie.200700430",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2007-05-25",
"series_number": "22",
"volume": "46",
"issue": "22",
"pages": "4077-4080"
},
{
"id": "authors:adqyh-g1b40",
"collection": "authors",
"collection_id": "adqyh-g1b40",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-084852047",
"type": "article",
"title": "Synthesis of 2-Quinuclidonium by Eliminating Water: Experimental Quantification of the High Basicity of Extremely Twisted Amides",
"author": [
{
"family_name": "Ly",
"given_name": "Tony",
"clpid": "Ly-Tony"
},
{
"family_name": "Krout",
"given_name": "Michael",
"clpid": "Krout-M"
},
{
"family_name": "Pham",
"given_name": "Don K.",
"clpid": "Pham-Don-K"
},
{
"family_name": "Tani",
"given_name": "Kousuke",
"clpid": "Tani-Kousuke"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Julian",
"given_name": "Ryan R.",
"orcid": "0000-0003-1580-8355",
"clpid": "Julian-R-R"
}
],
"abstract": "The chemical properties of an extremely twisted amide are examined quantitatively for the first time. The predicted high basicity of 2-quinuclidonium is confirmed experimentally by measuring the gas-phase proton affinity using the extended kinetic method. Fragmentation of this molecule further reveals that the lack of resonance stabilization weakens the amide bond. Furthermore, a new route for synthesizing 2-quinuclidonium by eliminating water is demonstrated in the gas phase.",
"doi": "10.1021/ja067703m",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2007-02-21",
"series_number": "7",
"volume": "129",
"issue": "7",
"pages": "1864-1865"
},
{
"id": "authors:kyqhw-tx445",
"collection": "authors",
"collection_id": "kyqhw-tx445",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161128-080903512",
"type": "article",
"title": "The synthesis of C-3\u03b2 functionalized indoles via a hydroboration/Suzuki\u2013Miyaura coupling sequence",
"author": [
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A method for the functionalization of C-3\u03b2 of vinyl indoles is described. The procedure involves a hydroboration, followed by a Suzuki\u2013Miyaura cross-coupling with the intermediate alkyl borane. Triflates, bromides, and iodides are suitable coupling partners, allowing access to a variety of elaborated indole compounds.",
"doi": "10.1016/j.tetlet.2006.09.112",
"pmcid": "PMC1832155",
"issn": "0040-4039",
"publisher": "Elsevier",
"publication": "Tetrahedron Letters",
"publication_date": "2006-11-27",
"series_number": "48",
"volume": "47",
"issue": "48",
"pages": "8579-8582"
},
{
"id": "authors:j191f-j9p18",
"collection": "authors",
"collection_id": "j191f-j9p18",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170223-142410037",
"type": "article",
"title": "Convergent and Diastereoselective Synthesis of the Polycyclic Pyran Core of Saudin",
"author": [
{
"family_name": "Tambar",
"given_name": "Uttam K.",
"clpid": "Tambar-U-K"
},
{
"family_name": "Kano",
"given_name": "Taichi",
"clpid": "Kano-Taichi"
},
{
"family_name": "Zepernick",
"given_name": "John F.",
"clpid": "Zepernick-J-F"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The natural product saudin was found to induce hypoglycemia in mice and, therefore, could be an appealing lead structure for the development of new agents to treat diabetes. A diastereoselective tandem Stille-oxa-electrocyclization reaction has been developed which provides access to the core structure of saudin in a rapid and convergent manner. This new reaction has been extended to the convergent preparation of a series of polycyclic pyran systems. Progress has been made on the advancement of these complex pyran systems toward the natural product. A complete account of these synthetic efforts is presented.",
"doi": "10.1021/jo061236+",
"issn": "0022-3263",
"publisher": "American Chemical Society",
"publication": "Journal of Organic Chemistry",
"publication_date": "2006-10-27",
"series_number": "22",
"volume": "71",
"issue": "22",
"pages": "8357-8364"
},
{
"id": "authors:ekt4c-agk78",
"collection": "authors",
"collection_id": "ekt4c-agk78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:GARcc06",
"type": "article",
"title": "A unified synthetic approach to the pyrazinone dragmacidins",
"author": [
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-N-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "This review describes recent developments from our laboratory involving the synthesis of the structurally complex, pyrazinone-containing dragmacidin alkaloids.",
"doi": "10.1039/b605929e",
"issn": "1359-7345",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Communications",
"publication_date": "2006-09-25",
"series_number": "36",
"volume": "2006",
"issue": "36",
"pages": "3769-3779"
},
{
"id": "authors:8tt5e-aea78",
"collection": "authors",
"collection_id": "8tt5e-aea78",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170221-152140812",
"type": "article",
"title": "A Convergent and Enantioselective Synthesis of (+)-Amurensinine via Selective C\u2212H and C\u2212C Bond Insertion Reactions",
"author": [
{
"family_name": "Tambar",
"given_name": "Uttam K.",
"clpid": "Tambar-U-K"
},
{
"family_name": "Ebner",
"given_name": "David C.",
"clpid": "Ebner-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A convergent and enantioselective synthesis of the natural product amurensinine is described. The synthetic strategy takes advantage of mild and selective C\u2212H and C\u2212C bond insertion reactions, in addition to the palladium-catalyzed aerobic oxidative kinetic resolution recently developed in these laboratories.",
"doi": "10.1021/ja0651815",
"pmcid": "PMC2529249",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2006-09-13",
"series_number": "36",
"volume": "128",
"issue": "36",
"pages": "11752-11753"
},
{
"id": "authors:7s5p8-tp326",
"collection": "authors",
"collection_id": "7s5p8-tp326",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-073849342",
"type": "article",
"title": "Catalytic Enantioselective Decarboxylative Protonation",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Nishimata",
"given_name": "Toyoki",
"clpid": "Nishimata-Toyoki"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "We report a highly enantioselective, general catalytic system for the facile synthesis of tertiary stereocenters by protonation adjacent to cyclic ketones. The method relies on catalytic decarboxylative protonation of readily accessible racemic quaternary \u03b2-ketoesters. A range of substituted cycloalkanone compounds can be accessed through this process with high levels of enantioselectivity.",
"doi": "10.1021/ja063335a",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2006-09-06",
"series_number": "35",
"volume": "128",
"issue": "35",
"pages": "11348-11349"
},
{
"id": "authors:z7qt7-8qj22",
"collection": "authors",
"collection_id": "z7qt7-8qj22",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-075015251",
"type": "article",
"title": "The Catalytic Enantioselective, Protecting Group-Free Total Synthesis of (+)-Dichroanone",
"author": [
{
"family_name": "McFadden",
"given_name": "Ryan M.",
"clpid": "McFadden-R-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Herein we report the first enantioselective total synthesis of (+)-dichroanone, confirming the absolute configuration of the natural product. This protecting group-free route features the first application of our enantioselective Tsuji allylation in the context of a natural product total synthesis. Additionally, this 11-step preparation of the molecule from commercial material features a novel Kumada-aromatization strategy and a rapid sequence for the conversion of a phenol to a hydroxy-p-benzoquinone.",
"doi": "10.1021/ja061853f",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2006-06-21",
"series_number": "24",
"volume": "128",
"issue": "24",
"pages": "7738-7739"
},
{
"id": "authors:zmvhd-2z473",
"collection": "authors",
"collection_id": "zmvhd-2z473",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150319-100435030",
"type": "article",
"title": "Synthesis and structural analysis of 2-quinuclidonium tetrafluoroborate",
"author": [
{
"family_name": "Tani",
"given_name": "Kousuke",
"clpid": "Tani-Kousuke"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The amide functional group is one of the most fundamental motifs found in chemistry and biology, and it has been studied extensively for the past century. Typical acyclic amides are planar. But the amide groups of bicyclic bridgehead lactams are highly twisted, and this distortion from planarity can dramatically affect the stability and reactivity of these amides; it also increases the basicity of the nitrogen so that it often behaves more like an amine than a typical planar amide. As a result, the structures and reactivity profiles of these 'anti-Bredt' amides differ significantly from those of planar amides. It is possible that this twisting phenomenon is not exclusive to cyclic systems\u2014non-planarity may also be a critical biological design element that leads to amide ground-state destabilization and alters the reactivity, selectivity and mechanism of various protein and enzymatic processes (such as amide hydrolysis). The intriguing qualities of these twisted amides were first recognized in 1938 (ref. 11), wherein one of the simplest families was introduced\u2014molecules containing the 1-azabicyclo[2.2.2]octan-2-one system. But the parent member of this group, 2-quinuclidone (molecule 1 in this paper), has not yet been unambiguously synthesized. Here, we report the chemical synthesis, isolation and full characterization of the HBF_4 salt of 1. Critical to the success of the synthesis and isolation was the decision to generate 1 by a route other than classical amide bond formation. We anticipate that these results will provide a greater understanding of the properties of amide bonds.",
"doi": "10.1038/nature04842",
"issn": "0028-0836",
"publisher": "Nature Publishing Group",
"publication": "Nature",
"publication_date": "2006-06-08",
"series_number": "7094",
"volume": "441",
"issue": "7094",
"pages": "731-734"
},
{
"id": "authors:mvehe-wfx25",
"collection": "authors",
"collection_id": "mvehe-wfx25",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:MEYcc06",
"type": "article",
"title": "2-Diazoacetoacetic acid, an efficient and convenient reagent for the synthesis of alpha-diazo-beta-ketoesters",
"author": [
{
"family_name": "Meyer",
"given_name": "Michael E.",
"clpid": "Meyer-M-E"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The formation of various alpha-diazo acetoacetic esters can be obtained in a single transformation with good to excellent yields using readily available 2-diazoacetoacetic acid.",
"doi": "10.1039/b517719g",
"issn": "1359-7345",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Communications",
"publication_date": "2006-03-28",
"series_number": "12",
"volume": "2006",
"issue": "12",
"pages": "1316-1318"
},
{
"id": "authors:je34y-zpz47",
"collection": "authors",
"collection_id": "je34y-zpz47",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170223-112338543",
"type": "article",
"title": "Effects of a Modified Dye-Labeled Nucleotide Spacer Arm on Incorporation by Thermophilic DNA Polymerases",
"author": [
{
"family_name": "Lacenere",
"given_name": "Christopher J.",
"clpid": "Lacenere-Christopher-J"
},
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-Neil-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Quake",
"given_name": "Stephen R.",
"orcid": "0000-0002-1613-0809",
"clpid": "Quake-Stephen-R"
}
],
"abstract": "The ability of eight commercially available thermophilic DNA polymerases to sequentially incorporate fluorescently labeled nucleotides sequentially was analyzed by a gel based primer extension assay. Cy5-dUTP or a variant nucleotide in which the linker had been lengthened by 14 atoms between the dye and the nucleobase were compared. We found that the Cy5-dUTP with a longer linker resulted in longer primer extension lengths. Furthermore, some of the assayed polymerases are capable of extending the primer to the full or near full length of 30 nucleotides using dye-labeled nucleotides exclusively.",
"doi": "10.1080/15257770500377714",
"issn": "1525-7770",
"publisher": "Taylor & Francis",
"publication": "Nucleosides, Nucleotides and Nucleic Acids",
"publication_date": "2006",
"series_number": "1",
"volume": "25",
"issue": "1",
"pages": "9-15"
},
{
"id": "authors:92614-fn932",
"collection": "authors",
"collection_id": "92614-fn932",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-152155230",
"type": "article",
"title": "Oxidative Cyclizations in a Nonpolar Solvent Using Molecular Oxygen and Studies on the Stereochemistry of Oxypalladation",
"author": [
{
"family_name": "Trend",
"given_name": "Raissa M.",
"clpid": "Trend-R-M"
},
{
"family_name": "Ramtohul",
"given_name": "Yeeman K.",
"clpid": "Ramtohul-Y-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Oxidative cyclizations of a variety of heteroatom nucleophiles onto unactivated olefins are catalyzed by palladium(II) and pyridine in the presence of molecular oxygen as the sole stoichiometric oxidant in a nonpolar solvent (toluene). Reactivity studies of a number of N-ligated palladium complexes show that chelating ligands slow the reaction. Nearly identical conditions are applicable to five different types of nucleophiles:\u2009 phenols, primary alcohols, carboxylic acids, a vinylogous acid, and amides. Electron-rich phenols are excellent substrates, and multiple olefin substitution patterns are tolerated. Primary alcohols undergo oxidative cyclization without significant oxidation to the aldehyde, a fact that illustrates the range of reactivity available from various Pd(II) salts under differing conditions. Alcohols can form both fused and spirocyclic ring systems, depending on the position of the olefin relative to the tethered alcohol; the same is true of the acid derivatives. The racemic conditions served as a platform for the development of an enantioselective reaction. Experiments with stereospecifically deuterated primary alcohol substrates rule out a \"Wacker-type\" mechanism involving anti oxypalladation and suggest that the reaction proceeds by syn oxypalladation for both mono- and bidentate ligands. In contrast, cyclizations of deuterium-labeled carboxylic acid substrates undergo anti oxypalladation.",
"doi": "10.1021/ja055534k",
"pmcid": "PMC2585987",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2005-12-21",
"series_number": "50",
"volume": "127",
"issue": "50",
"pages": "17778-17788"
},
{
"id": "authors:mg30p-xk551",
"collection": "authors",
"collection_id": "mg30p-xk551",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-153759053",
"type": "article",
"title": "Deracemization of Quaternary Stereocenters by Pd-Catalyzed Enantioconvergent Decarboxylative Allylation of Racemic \u03b2-Ketoesters",
"author": [
{
"family_name": "Mohr",
"given_name": "Justin T.",
"orcid": "0000-0002-7005-3322",
"clpid": "Mohr-J-T"
},
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Harned",
"given_name": "Andrew M.",
"clpid": "Harned-A-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Stereochemical alchemy! Racemic allyl \u03b2-ketoesters allow the regiocontrolled formation of enolates, where the same catalyst is intimately involved in both the stereoablative (C-C bond-breaking) and stereoselective (C-C bond-forming) steps. This mechanistic and practical insight led to the formation of multiple quaternary carbon stereocenters in a single cascade reaction (see scheme).",
"doi": "10.1002/anie.200502018",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2005-10-28",
"series_number": "42",
"volume": "44",
"issue": "42",
"pages": "6924-6927"
},
{
"id": "authors:z9smt-egv61",
"collection": "authors",
"collection_id": "z9smt-egv61",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-144318676",
"type": "article",
"title": "Progress toward the Total Synthesis of Saudin: Development of a Tandem Stille-Oxa-Electrocyclization Reaction",
"author": [
{
"family_name": "Tambar",
"given_name": "Uttam K.",
"clpid": "Tambar-U-K"
},
{
"family_name": "Kano",
"given_name": "Taichi",
"clpid": "Kano-Taichi"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A diastereoselective tandem Stille-oxa-electrocyclization reaction provides access to the core of the diterpenoid natural product saudin. Additionally, this new reaction sequence was extended to the convergent preparation of related polycyclic pyran systems.",
"doi": "10.1021/ol050705b",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2005-06-09",
"series_number": "12",
"volume": "7",
"issue": "12",
"pages": "2413-2416"
},
{
"id": "authors:dxxb4-18j65",
"collection": "authors",
"collection_id": "dxxb4-18j65",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-150113004",
"type": "article",
"title": "Heterogeneous Reductive Isomerization Reaction Using Catalytic Pd/C and H_2",
"author": [
{
"family_name": "Caspi",
"given_name": "Daniel D.",
"clpid": "Caspi-D-D"
},
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-N-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A highly selective catalytic reductive isomerization reaction is described. The extremely mild and neutral reaction conditions (10% Pd/C, H_2, and MeOH at 0 \u00b0C) tolerate a wide range of functional groups and generally result in excellent yields. Mechanistic studies suggest that this reaction does not proceed via a stepwise reduction/elimination sequence or a \u03c0-allylpalladium intermediate.",
"doi": "10.1021/ol050952f",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2005-06-09",
"series_number": "12",
"volume": "7",
"issue": "12",
"pages": "2513-2516"
},
{
"id": "authors:8p14n-x4863",
"collection": "authors",
"collection_id": "8p14n-x4863",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-093427303",
"type": "article",
"title": "Development of an Enantiodivergent Strategy for the Total Synthesis of (+)- and (\u2212)-Dragmacidin F from a Single Enantiomer of Quinic Acid",
"author": [
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-N-K"
},
{
"family_name": "Caspi",
"given_name": "Daniel D.",
"clpid": "Caspi-D-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An enantiodivergent strategy for the total chemical synthesis of both (+)- and (\u2212)-dragmacidin F beginning from a single enantiomer of quinic acid has been developed and successfully implemented. Although unique, the synthetic routes to these antipodes share a number of key features, including novel reductive isomerization reactions, Pd(II)-mediated oxidative carbocyclization reactions, halogen-selective Suzuki couplings, and high-yielding late-stage Neber rearrangements.",
"doi": "10.1021/ja050586v",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2005-04-27",
"series_number": "16",
"volume": "127",
"issue": "16",
"pages": "5970-5978"
},
{
"id": "authors:a495w-pyd69",
"collection": "authors",
"collection_id": "a495w-pyd69",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-085357234",
"type": "article",
"title": "The Direct Acyl-Alkylation of Arynes",
"author": [
{
"family_name": "Tambar",
"given_name": "Uttam K.",
"clpid": "Tambar-U-K"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "An efficient and mild acyl-alkylation of arynes is described. The method is used to synthesize medium-sized carbocycles by the ring-expansion of cyclic \u03b2-ketoesters.",
"doi": "10.1021/ja050859m",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2005-04-20",
"series_number": "15",
"volume": "127",
"issue": "15",
"pages": "5340-5341"
},
{
"id": "authors:4k95m-j2w81",
"collection": "authors",
"collection_id": "4k95m-j2w81",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:GARcc05",
"type": "article",
"title": "A ligand-free solid-supported system for Sonogashira couplings: applications in nucleoside chemistry",
"author": [
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-Neil-K"
},
{
"family_name": "Woodroofe",
"given_name": "Carolyn C.",
"clpid": "Woodroofe-Carolyn-C"
},
{
"family_name": "Lacenere",
"given_name": "Christopher J.",
"clpid": "Lacenere-Christopher-J"
},
{
"family_name": "Quake",
"given_name": "Stephen R.",
"clpid": "Quake-Stephen-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A mild heterogeneous, ligand-free protocol for Sonogashira and Heck couplings has been developed and used to access several biologically important deoxynucleoside derivatives in a facile manner.",
"doi": "10.1039/b505737j",
"issn": "1359-7345",
"publisher": "Royal Society of Chemistry",
"publication": "Chemical Communications",
"publication_date": "2005",
"series_number": "36",
"volume": "2005",
"issue": "36",
"pages": "4551-4553"
},
{
"id": "authors:7hz51-05y69",
"collection": "authors",
"collection_id": "7hz51-05y69",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-141008792",
"type": "article",
"title": "The Enantioselective Tsuji Allylation",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first catalytic enantioselective examples of the Tsuji allylation using enol carbonates and enol silanes are described. The products possess a quaternary stereogenic center and are useful building blocks for synthetic chemistry.",
"doi": "10.1021/ja044812x",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2004-11-24",
"series_number": "46",
"volume": "126",
"issue": "46",
"pages": "15044-15045"
},
{
"id": "authors:6zrh7-rq465",
"collection": "authors",
"collection_id": "6zrh7-rq465",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170420-084322708",
"type": "article",
"title": "The Enantioselective Tsuji Allylation",
"author": [
{
"family_name": "Behenna",
"given_name": "Douglas C.",
"clpid": "Behenna-D-C"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first catalytic enantioselective examples of the Tsuji allylation using enol carbonates and enol silanes are described. The products possess a quaternary stereogenic center and are useful building blocks for synthetic chemistry.",
"doi": "10.1021/ja044812x",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2004-11-24",
"series_number": "46",
"volume": "126",
"issue": "46",
"pages": "15044-15045"
},
{
"id": "authors:b1prn-2zv46",
"collection": "authors",
"collection_id": "b1prn-2zv46",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170221-114810808",
"type": "article",
"title": "Direct Oxidative Heck Cyclizations: Intramolecular Fujiwara-Moritani Arylations for the Synthesis of Functionalized Benzofurans and Dihydrobenzofurans",
"author": [
{
"family_name": "Zhang",
"given_name": "Haiming",
"orcid": "0000-0002-2139-2598",
"clpid": "Zhang-Haiming"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "No extra functionalization step is required for palladium(II)-catalyzed oxidative carbocyclizations like that shown, which provide highly substituted benzofuran and dihydrobenzofuran derivatives by net dehydrogenation. The mechanism is similar to that of Heck cyclizations. Products containing quaternary carbon stereocenters can be obtained in diastereomerically pure form.",
"doi": "10.1002/anie.200461294",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2004-11-17",
"series_number": "45",
"volume": "43",
"issue": "45",
"pages": "6144-6148"
},
{
"id": "authors:c5wzr-1nf40",
"collection": "authors",
"collection_id": "c5wzr-1nf40",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-153256032",
"type": "article",
"title": "The Total Synthesis of (+)-Dragmacidin F",
"author": [
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-N-K"
},
{
"family_name": "Caspi",
"given_name": "Daniel D.",
"clpid": "Caspi-D-D"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first total synthesis of (+)-dragmacidin F has been accomplished, establishing the absolute configuration of this biologically important, antiviral marine alkaloid. The convergent route described features a palladium-mediated oxidative pyrrole carbocylization reaction to construct the [3.3.1] bicycle, as well as a highly selective Suzuki coupling to build the carbon skeleton of the natural product. A late-stage Neber rearrangement allows for the facile installation of the aminoimidazole moiety to provide (+)-dragmacidin F.",
"doi": "10.1021/ja046695b",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2004-08-11",
"series_number": "31",
"volume": "126",
"issue": "31",
"pages": "9552-9553"
},
{
"id": "authors:e6am0-0j945",
"collection": "authors",
"collection_id": "e6am0-0j945",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-152829202",
"type": "article",
"title": "A Computational Model Relating Structure and Reactivity in Enantioselective Oxidations of Secondary Alcohols by (\u2212)-Sparteine\u2212Pd^(II) Complexes",
"author": [
{
"family_name": "Nielsen",
"given_name": "Robert J.",
"orcid": "0000-0002-7962-0186",
"clpid": "Nielsen-R-J"
},
{
"family_name": "Keith",
"given_name": "Jason M.",
"orcid": "0000-0002-5292-397X",
"clpid": "Keith-J-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
}
],
"abstract": "The key interactions responsible for the unique reactivity of (\u2212)-sparteine\u2212PdX_2 complexes (X = chloride, acetate) in the enantioselective oxidation of secondary alcohols have been elucidated using quantum mechanics (B3LYP DFT with the PBF polarizable continuum solvent model). From examining many possible pathways, we find the mechanism involves:\u2009 (1) substitution of the alcohol in place of an X-group, (2) deprotonation of the bound alcohol by the deposed anion and free sparteine, (3) \u03b2-hydride elimination through a four-coordinate transition state in which the second anion is displaced but tightly associated, (4) replacement of the ketone product with the associated anion. The enantioselectivities observed under base-rich reaction conditions follow directly from calculated energies of diastereomeric \u03b2-hydride elimination transition states incorporating (R) and (S) substrates. This relationship reveals an important role of the anion, namely to communicate the steric interaction of the ligand on one side of the PdII square plane and the substrate on the other side. When no anion is included, no enantioselectivity is predicted. Locating these transition states in different solvents shows that higher dielectrics stabilize the charge separation between the anion and metal and draw the anion farther into solution. Thus, the solvent influences the barrier height (rate) and selectivity of the oxidation.",
"doi": "10.1021/ja031911m",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2004-06-30",
"series_number": "25",
"volume": "126",
"issue": "25",
"pages": "7967-7974"
},
{
"id": "authors:617h2-z2647",
"collection": "authors",
"collection_id": "617h2-z2647",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-072248452",
"type": "article",
"title": "An Experimentally Derived Model for Stereoselectivity in the Aerobic Oxidative Kinetic Resolution of Secondary Alcohols by (Sparteine)PdCl_2",
"author": [
{
"family_name": "Trend",
"given_name": "Raissa M.",
"clpid": "Trend-R-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A model for asymmetric induction in palladium-catalyzed aerobic oxidative kinetic resolution is described. The model is based on coordination complexes and general reactivity trends of the parent (sp)PdCl2 catalyst. The first example of a nonracemic chiral palladium alkoxide complex is presented, and exhibits the subtle steric influences of the C1symmetric ligand sparteine.",
"doi": "10.1021/ja039551q",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2004-04-14",
"series_number": "14",
"volume": "126",
"issue": "14",
"pages": "4482-4483"
},
{
"id": "authors:axt8k-8fa97",
"collection": "authors",
"collection_id": "axt8k-8fa97",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-074904738",
"type": "article",
"title": "Substituent Effects and Nearly Degenerate Transition States: Rational Design of Substrates for the Tandem Wolff\u2212Cope Reaction",
"author": [
{
"family_name": "Su",
"given_name": "Julius T.",
"clpid": "Su-Julius-T"
},
{
"family_name": "Sarpong",
"given_name": "Richmond",
"orcid": "0000-0002-0028-6323",
"clpid": "Sarpong-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Goddard",
"given_name": "William A., III",
"orcid": "0000-0003-0097-5716",
"clpid": "Goddard-W-A-III"
}
],
"abstract": "The substrate scope for a ketene-assisted Cope (tandem Wolff\u2212Cope) reaction is elucidated from first-principles quantum mechanics. An alternate pathway (trans) leading to an undesired and unstable product lies perilously close (\u223c2.5 kcal/mol) to the primary (cis) reaction pathway; this near-degeneracy arises from preferential ketene stabilization of a radicaloid trans transition state over an aromatic cis transition state. Normally, substitution at \"forbidden\" sites causes the alternate pathway to be favored and the reaction to fail, but using simple conformational analysis principles we design substrates that defy this rule.",
"doi": "10.1021/ja037716p",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2004-01-14",
"series_number": "1",
"volume": "126",
"issue": "1",
"pages": "24-25"
},
{
"id": "authors:cms8q-pdm31",
"collection": "authors",
"collection_id": "cms8q-pdm31",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-145714988",
"type": "article",
"title": "Palladium-Catalyzed Oxidative Kinetic Resolution with Ambient Air as the Stoichiometric Oxidation Gas",
"author": [
{
"family_name": "Bagdanoff",
"given_name": "Jeffrey T.",
"clpid": "Bagdanoff-J-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "Air is enough to mediate the highly enantioselective oxidation of secondary alcohols at room temperature with palladium(II) and sparteine in nonflammable solvents. Examination of the role of solvents capable of hydrogen bonding and their ability to solvate halide anions led to a novel set of conditions for the highly enantioselective oxidative kinetic resolution of secondary alcohols.",
"doi": "10.1002/anie.200352444",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2004-01-05",
"series_number": "3",
"volume": "43",
"issue": "3",
"pages": "353-357"
},
{
"id": "authors:9n436-bkd09",
"collection": "authors",
"collection_id": "9n436-bkd09",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-075818295",
"type": "article",
"title": "The Total Synthesis of (\u2212)-Lemonomycin",
"author": [
{
"family_name": "Ashley",
"given_name": "Eric R.",
"clpid": "Ashley-E-R"
},
{
"family_name": "Cruz",
"given_name": "Ernest G.",
"clpid": "Cruz-E-G"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first total synthesis of the novel glycosylated tetrahydroisoquinoline antitumor antibiotic (\u2212)-lemonomycin has been accomplished (15 steps from 9). The highly convergent synthesis relies on a key asymmetric dipolar cycloaddition to set the stereochemistry of the aglycone core, a Suzuki fragment coupling to connect the diazabicycle to the aryl subunit, and a stereoselective Pictet\u2212Spengler reaction that incorporates the aminoglycoside subunit directly into the core structure without the need for late-stage glycosylation or protecting group manipulations. The novel aminoglycoside was prepared using a highly diastereoselective Felkin-controlled acetate aldol addition reaction to a threonine-derived ketone.",
"doi": "10.1021/ja039223q",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2003-12-10",
"series_number": "49",
"volume": "125",
"issue": "49",
"pages": "15000-15001"
},
{
"id": "authors:8b097-t2614",
"collection": "authors",
"collection_id": "8b097-t2614",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-143652773",
"type": "article",
"title": "The Development of a Facile Tandem Wolff/Cope Rearrangement for the Synthesis of Fused Carbocyclic Skeletons",
"author": [
{
"family_name": "Sarpong",
"given_name": "Richmond",
"orcid": "0000-0002-0028-6323",
"clpid": "Sarpong-R"
},
{
"family_name": "Su",
"given_name": "Julius T.",
"clpid": "Su-Julius-T"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A set of mild processes for the conversion of vinyl cyclopropyl diazo ketones to highly functionalized cycloheptadienones and vinyl cyclopentenones by use of a target-inspired tandem Wolff/Cope rearrangement sequence is described. A divergent reaction course of the vinyl cyclopropyl diazo ketone substrates under sono- or photochemical activation provides good to excellent yields (55\u221298%) of the product cycloheptadienones and vinyl cyclopentenones.",
"doi": "10.1021/ja037587c",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2003-11-12",
"series_number": "45",
"volume": "125",
"issue": "45",
"pages": "13624-13625"
},
{
"id": "authors:z5zec-vc047",
"collection": "authors",
"collection_id": "z5zec-vc047",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170216-082726177",
"type": "article",
"title": "Catalytic C\u2212H Bond Functionalization with Palladium(II): Aerobic Oxidative Annulations of Indoles",
"author": [
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A palladium-catalyzed aerobic oxidative annulation of indoles is described. We have demonstrated that a variety of factors influence these cyclizations, and in particular the electronic nature of the pyridine ligand is crucial. It is also remarkable that these oxidative cyclizations can proceed in good yield despite background oxidative decomposition pathways, testament to the facile nature with which molecular oxygen can serve as the direct oxidant for Pd(0). We have also shown that the mechanism most likely involves initial indole palladation (formal C\u2212H bond activation) followed by migratory insertion and \u03b2-hydrogen elimination.",
"doi": "10.1021/ja035054y",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2003-08-13",
"series_number": "32",
"volume": "125",
"issue": "32",
"pages": "9578-9579"
},
{
"id": "authors:7r236-4tx48",
"collection": "authors",
"collection_id": "7r236-4tx48",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170221-131404095",
"type": "article",
"title": "Palladium-Catalyzed Oxidative Wacker Cyclizations in Nonpolar Organic Solvents with Molecular Oxygen: A Stepping Stone to Asymmetric Aerobic Cyclizations",
"author": [
{
"family_name": "Trend",
"given_name": "Raissa M.",
"clpid": "Trend-R-M"
},
{
"family_name": "Ramtohul",
"given_name": "Yeeman K.",
"clpid": "Ramtohul-Y-K"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A variety of Pd-catalyzed oxidative nucleophile/alkene cyclizations proceeds in excellent yield under simple aerobic conditions in nonpolar media (Pd catalyst, pyridine, and O_2 in toluene). Nucleophiles for these cyclizations include phenols, carboxylic acids, amides, and primary alcohols. Additionally, enantioselective catalysis is feasible with a Pd-sparteine system (see picture). Enantioselectivities of up to 90\u2009% ee are observed for simple phenol/alkene cyclizations.",
"doi": "10.1002/anie.200351196",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2003-06-24",
"series_number": "25",
"volume": "42",
"issue": "25",
"pages": "2892-2895"
},
{
"id": "authors:fn8tz-vj068",
"collection": "authors",
"collection_id": "fn8tz-vj068",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-152031857",
"type": "article",
"title": "Gas-Phase Synthesis of Charged Copper and Silver Fischer Carbenes from Diazomalonates: Mechanistic and Conformational Considerations in Metal-Mediated Wolff Rearrangements",
"author": [
{
"family_name": "Julian",
"given_name": "Ryan R.",
"orcid": "0000-0003-1580-8355",
"clpid": "Julian-R-R"
},
{
"family_name": "May",
"given_name": "Jeremy A.",
"clpid": "May-J-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Beauchamp",
"given_name": "J. L.",
"orcid": "0000-0001-8839-4822",
"clpid": "Beauchamp-J-L"
}
],
"abstract": "Copper(I) and silver(I) Fischer carbenes are synthesized in the gas phase. Various diazomalonate-based compounds with an attached metal ion are introduced into the gas phase by electrospray ionization and subjected to collisional activation. Loss of N2 generates a metastable Fischer carbene, which subsequently undergoes Wolff rearrangement and loss of CO. Further excitation leads to the loss of another CO molecule and the generation of a stable Fischer carbene. Isotopically labeled compounds are utilized to confirm the assignment of the products resulting from this process. DFT calculations are used to evaluate various mechanistic possibilities and to quantitatively assess the energetics of reactants and products. Silver(I) is shown to be more effective in facilitating Wolff rearrangement than copper(I), although both are more effective when compared to spectator charges such as sodium or a fixed quaternary nitrogen. Carbenes are not produced when copper(II), nickel(II), or a proton is used to form a quasi-molecular ion from the diazomalonate carbene precursor. Finally, trapping of the Fischer carbene by various functional groups attached through the open coordination site of the metal is investigated.",
"doi": "10.1021/ja028337j",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2003-04-16",
"series_number": "15",
"volume": "125",
"issue": "15",
"pages": "4478-4486"
},
{
"id": "authors:cw5w9-1pw32",
"collection": "authors",
"collection_id": "cw5w9-1pw32",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-145100100",
"type": "article",
"title": "Palladium-Catalyzed Enantioselective Oxidation of Alcohols: A Dramatic Rate Acceleration by Cs_2CO_3/t-BuOH",
"author": [
{
"family_name": "Bagdanoff",
"given_name": "Jeffrey T.",
"clpid": "Bagdanoff-J-T"
},
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The addition of Cs_2CO_3 and t-BuOH provides a dramatic rate acceleration in the palladium-catalyzed aerobic oxidative kinetic resolution of secondary alcohols while maintaining the selectivity of the process.",
"doi": "10.1021/ol027463p",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2003-03-20",
"series_number": "6",
"volume": "5",
"issue": "6",
"pages": "835-837"
},
{
"id": "authors:k66yv-y9p48",
"collection": "authors",
"collection_id": "k66yv-y9p48",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170223-161950902",
"type": "article",
"title": "Molecular Mousetraps: Gas-Phase Studies of the Covalent Coupling of Noncovalent Complexes Initiated by Reactive Carbenes Formed by Controlled Activation of Diazo Precursors",
"author": [
{
"family_name": "Julian",
"given_name": "Ryan R.",
"orcid": "0000-0003-1580-8355",
"clpid": "Julian-R-R"
},
{
"family_name": "May",
"given_name": "Jeremy A.",
"clpid": "May-J-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Beauchamp",
"given_name": "J. L.",
"orcid": "0000-0001-8839-4822",
"clpid": "Beauchamp-J-L"
}
],
"abstract": "The covalent linking of noncovalently bound host\u2013guest complexes in the gas phase is achieved by the formation of a highly reactive carbene from the host molecule, which is generated by collision-activated dissociation. Possible mechanisms for the resulting intermolecular reactions are explored by theory and experiment.",
"doi": "10.1002/anie.200390258",
"issn": "1433-7851",
"publisher": "Wiley",
"publication": "Angewandte Chemie International Edition",
"publication_date": "2003-03-03",
"series_number": "9",
"volume": "42",
"issue": "9",
"pages": "1012-1015"
},
{
"id": "authors:amz6m-00h40",
"collection": "authors",
"collection_id": "amz6m-00h40",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-142231422",
"type": "article",
"title": "The First Total Synthesis of Dragmacidin D",
"author": [
{
"family_name": "Garg",
"given_name": "Neil K.",
"clpid": "Garg-N-K"
},
{
"family_name": "Sarpong",
"given_name": "Richmond",
"orcid": "0000-0002-0028-6323",
"clpid": "Sarpong-R"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The first total synthesis of the biologically significant bis-indole alkaloid dragmacidin D (5) has been achieved. Thermal and electronic modulation provides the key for a series of palladium-catalyzed Suzuki cross-coupling reactions that furnished the core structure of the complex guanidine- and aminoimidazole-containing dragmacidins. Following this crucial sequence, a succession of meticulously controlled final events was developed leading to the completion of the natural product.",
"doi": "10.1021/ja027822b",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2002-11-06",
"series_number": "44",
"volume": "124",
"issue": "44",
"pages": "13179-13184"
},
{
"id": "authors:37gda-ad142",
"collection": "authors",
"collection_id": "37gda-ad142",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-150235551",
"type": "article",
"title": "Non-Carbonyl-Stabilized Metallocarbenoids in Synthesis: The Development of a Tandem Rhodium-Catalyzed Bamford\u2212Stevens/Thermal Aliphatic Claisen Rearrangement Sequence",
"author": [
{
"family_name": "May",
"given_name": "Jeremy A.",
"clpid": "May-J-A"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A tandem rhodium-catalyzed Bamford\u2212Stevens/Claisen rearrangement is presented. The tandem reaction uses Eschenmoser hydrazones for the in situ generation of non-carbonyl-stabilized diazo alkanes, which are presumably intercepted by Rh(II) catalysts to induce a 1,2-hydride migration. This sequence provides high levels of stereocontrol for the generation of simple acyclic (Z)-enol ethers. These enol ethers undergo either thermal or Lewis acid accelerated Claisen rearrangements to provide products of high diastereopurity. Also presented are cascade reactions, wherein a third chemical step occurs after the initial tandem sequence (i.e., Bamford\u2212Stevens/Claisen/ene and Bamford\u2212Stevens/Claisen/Cope).",
"doi": "10.1021/ja028020j",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2002-10-23",
"series_number": "42",
"volume": "124",
"issue": "42",
"pages": "12426-12427"
},
{
"id": "authors:9bg7j-as593",
"collection": "authors",
"collection_id": "9bg7j-as593",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-135249615",
"type": "article",
"title": "Progress toward the Synthesis of Garsubellin A and Related Phloroglucins: The Direct Diastereoselective Synthesis of the Bicyclo[3.3.1]nonane Core",
"author": [
{
"family_name": "Spessard",
"given_name": "Sarah J.",
"clpid": "Spessard-S-J"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "A highly diastereoselective single-step cyclization reaction provides access to the bicyclo[3.3.1]nonane core of the polyprenylated phloroglucin natural product garsubellin A. Further elaboration to a more functionalized analogue involves a sequential Claisen rearrangement/Grubbs olefin cross-metathesis strategy. Additionally, this strategy was extended to the preparation of the bis-quaternary carbon array found at the bridgehead positions of the phloroglucin natural products.",
"doi": "10.1021/ol025968+",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2002-05-30",
"series_number": "11",
"volume": "4",
"issue": "11",
"pages": "1943-1946"
},
{
"id": "authors:7appy-f1q40",
"collection": "authors",
"collection_id": "7appy-f1q40",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-134639074",
"type": "article",
"title": "The Palladium-Catalyzed Oxidative Kinetic Resolution of Secondary Alcohols with Molecular Oxygen",
"author": [
{
"family_name": "Ferreira",
"given_name": "Eric M.",
"clpid": "Ferreira-E-M"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
}
],
"abstract": "The oxidation of secondary alcohols is one of the most common and well-studied reactions in chemistry. Although excellent catalytic enantioselective methods exist for a variety of oxidation processes, such as epoxidation, dihydroxylation, and aziridination, it is surprising that there are relatively few catalytic enantioselective examples of the ubiquitous alcohol oxidation. In connection with a general program dealing with the discovery of new catalytic oxidation systems, we present herein the development of a catalytic oxidative kinetic resolution of secondary alcohols that uses molecular oxygen as the terminal oxidant (see Scheme 1).",
"doi": "10.1021/ja015791z",
"issn": "0002-7863",
"publisher": "American Chemical Society",
"publication": "Journal of the American Chemical Society",
"publication_date": "2001-08-08",
"series_number": "31",
"volume": "123",
"issue": "31",
"pages": "7725-7726"
},
{
"id": "authors:aqngw-00665",
"collection": "authors",
"collection_id": "aqngw-00665",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170215-134104826",
"type": "article",
"title": "Synthesis of C(3) Benzofuran-Derived Bisaryl Quaternary Centers: Approaches to Diazonamide A",
"author": [
{
"family_name": "Fuerst",
"given_name": "Douglas E.",
"clpid": "Fuerst-D-E"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Wood",
"given_name": "John L.",
"clpid": "Wood-J-L"
}
],
"abstract": "Two complementary strategies for the synthesis of the diazonamide A bisaryl quaternary center are described. The first strategy relies upon an extremely facile tandem cyclopropanation/ring-opening sequence, which has proven amenable to chiral catalysis to provide enantioenriched material. The second strategy relies upon a more concise alkylation route ideal for material advancement.",
"doi": "10.1021/ol006578v",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2000-11-02",
"series_number": "22",
"volume": "2",
"issue": "22",
"pages": "3521-3523"
},
{
"id": "authors:0zd3f-hd554",
"collection": "authors",
"collection_id": "0zd3f-hd554",
"cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-101505337",
"type": "article",
"title": "Mechanistic Insights into the Factors Determining Exo\u2212EndoSelectivity in the Lewis Acid-Catalyzed Diels\u2212Alder Reaction of 1,3-Dienes with 2-Cycloalkenones",
"author": [
{
"family_name": "Ge",
"given_name": "Min",
"clpid": "Ge-Min"
},
{
"family_name": "Stoltz",
"given_name": "Brian M.",
"orcid": "0000-0001-9837-1528",
"clpid": "Stoltz-B-M"
},
{
"family_name": "Corey",
"given_name": "E. J.",
"clpid": "Corey-E-J"
}
],
"abstract": "We adduce evidence that the asynchronous, Lewis acid-catalyzed Diels\u2212Alder reaction of 2-cycloalkenones with nonsimple \u03b1,\u03b2-enones can proceed via transition states in which the 1,3-diene subunit is skewed, i.e., nonplanar, with profound effects on the ratio of exo and endo addition products.",
"doi": "10.1021/ol0060026",
"issn": "1523-7060",
"publisher": "American Chemical Society",
"publication": "Organic Letters",
"publication_date": "2000-06-29",
"series_number": "13",
"volume": "2",
"issue": "13",
"pages": "1927-1929"
}
]