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Ortiz E, Spinello BJ, Cho Y, Wu J, Krische MJ. Stereo- and Site-Selective Crotylation of Alcohol Proelectrophiles via Ruthenium-Catalyzed Hydrogen Auto-Transfer Mediated by Methylallene and Butadiene. Angew Chem Int Ed Engl 2022; 61:e202212814. [PMID: 36201364 PMCID: PMC9712268 DOI: 10.1002/anie.202212814] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Indexed: 11/06/2022]
Abstract
Iodide-bound ruthenium-JOSIPHOS complexes catalyze the redox-neutral C-C coupling of primary alcohols with methylallene (1,2-butadiene) or 1,3-butadiene to form products of anti-crotylation with good to excellent levels of diastereo- and enantioselectivity. Distinct from other methods, direct crotylation of primary alcohols in the presence of unprotected secondary alcohols is possible, enabling generation of spirastrellolide B (C9-C15) and leucascandrolide A (C9-C15) substructures in significantly fewer steps than previously possible.
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Affiliation(s)
| | | | - Yoon Cho
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712-1167 (USA)
| | - Jessica Wu
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712-1167 (USA)
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712-1167 (USA)
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2
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Stivala CE, Zbieg JR, Liu P, Krische MJ. Chiral Amines via Enantioselective π-Allyliridium- C, O-Benzoate-Catalyzed Allylic Alkylation: Student Training via Industrial-Academic Collaboration. Acc Chem Res 2022; 55:2138-2147. [PMID: 35830564 PMCID: PMC9608351 DOI: 10.1021/acs.accounts.2c00302] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
ConspectusCyclometalated π-allyliridium-C,O-benzoate complexes discovered in the Krische laboratory display unique amphiphilic properties, catalyzing both nucleophilic carbonyl allylation and electrophilic allylation of diverse amines as well as nitronates. Given the importance of chiral amines in FDA-approved small-molecule drugs, a collaboration with medicinal chemists at Genentech that included on-site graduate student internships was undertaken to explore and expand the scope of π-allyliridium-C,O-benzoate-catalyzed allylic amination and related processes. As described in this Account, our collective experimental studies have unlocked asymmetric allylic aminations of exceptionally broad utility and scope. Specifically, using racemic branched alkyl-substituted allylic acetate proelectrophiles, primary and secondary aliphatic or aromatic amines, including indoles, engage in highly regio- and enantioselective allylic amination. Additionally, unactivated nitronates were found to be competent nucleophilic partners for regio- and enantioselective allylic alkylation, enabling entry to β-stereogenic α-quaternary primary amines. Notably, these π-allyliridium-C,O-benzoate-catalyzed allylic substitutions, which display complete branched regioselectivity in reactions of alkyl-substituted allyl electrophiles, complement the scope of corresponding iridium phosphoramidite-catalyzed allylic aminations, which require aryl-substituted allyl electrophiles to promote high levels of branched regioselectivity. Computational, kinetic, ESI-CID-MS, and isotopic labeling studies were undertaken to understand the mechanism of these processes, including the origins of regio- and enantioselectivity. Isotopic labeling studies suggest that C-N bond formation occurs through outer-sphere addition to the π-allyl. DFT calculations corroborate C-N bond formation via outer-sphere addition and suggest that early transition states and distinct trans effects of diastereomeric chiral-at-iridium π-allyl complexes render the reaction less sensitive to steric effects, accounting for complete levels of branched regioselectivity in reactions of hindered amine and nitronate nucleophiles. Reaction progress kinetic analysis (RPKA) reveals a zero-order dependence on allyl acetate, a first-order dependence on the catalyst, and a fractional-order dependence on the amine. As corroborated by ESI-CID-MS analysis, the 0.4 kinetic order dependence on the amine may reflect the intervention of cesium-bridged amine dimers, which dissociate to form monomeric cesium amide nucleophiles. Hence, the requirement of cesium carbonate (vs lower alkali metal carbonates) in these processes may reside in cesium's capacity for Lewis acid-enhanced Brønsted acidification of the amine pronucleophile. Beyond the development of catalytic processes for the synthesis of novel chiral amines, the present research was conducted by graduate students who benefited from career development experiences associated with training in both academic and industrial laboratories.
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Affiliation(s)
- Craig E Stivala
- Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Jason R Zbieg
- Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Peng Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Michael J Krische
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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Ortiz E, Chang YH, Shezaf JZ, Shen W, Krische MJ. Stereo- and Site-Selective Conversion of Primary Alcohols to Allylic Alcohols via Ruthenium-Catalyzed Hydrogen Auto-Transfer Mediated by 2-Butyne. J Am Chem Soc 2022; 144:8861-8869. [PMID: 35503919 DOI: 10.1021/jacs.2c03614] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The first enantioselective ruthenium-catalyzed carbonyl vinylations via hydrogen autotransfer are described. Using a ruthenium-JOSIPHOS catalyst, primary alcohols 2a-2m and 2-butyne 1a are converted to chiral allylic alcohols 3a-3m with excellent levels of absolute stereocontrol. Notably, 1°,2°-1,3-diols participate in site-selective C-C coupling, enabling asymmetric carbonyl vinylation beyond premetalated reagents, exogenous reductants, or hydroxyl protecting groups. Using 2-propanol as a reductant, aldehydes dehydro-2a, 2l participate in highly enantioselective 2-butyne-mediated vinylation under otherwise identical reaction conditions. Regio-, stereo-, and site-selective vinylations mediated by 2-pentyne 1b to form adducts 3n, 3o, and epi-3o also are described. The tiglyl alcohol motif obtained upon butyne-mediated vinylation, which is itself found in diverse secondary metabolites, may be converted to commonly encountered polyketide stereodiads, -triads, and -tetrads, as demonstrated by the formation of adducts 4a-4d. The collective mechanistic studies, including deuterium labeling experiments, corroborate a catalytic cycle involving alcohol dehydrogenation to form a transient aldehyde and a ruthenium hydride, which engages in alkyne hydrometalation to form a nucleophilic vinylruthenium species that enacts carbonyl addition. A stereochemical model for carbonyl addition invoking formyl CH···I[Ru] and CH···O≡C[Ru] hydrogen bonds is proposed based on prior calculations and crystallographic data.
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Affiliation(s)
- Eliezer Ortiz
- University of Texas at Austin, Department of Chemistry, 105 East 24th Street, Austin, Texas 78712, United States
| | - Yu-Hsiang Chang
- University of Texas at Austin, Department of Chemistry, 105 East 24th Street, Austin, Texas 78712, United States
| | - Jonathan Z Shezaf
- University of Texas at Austin, Department of Chemistry, 105 East 24th Street, Austin, Texas 78712, United States
| | - Weijia Shen
- University of Texas at Austin, Department of Chemistry, 105 East 24th Street, Austin, Texas 78712, United States
| | - Michael J Krische
- University of Texas at Austin, Department of Chemistry, 105 East 24th Street, Austin, Texas 78712, United States
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4
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Doerksen RS, Meyer CC, Krische MJ. Feedstock Reagents in Metal-Catalyzed Carbonyl Reductive Coupling: Minimizing Preactivation for Efficiency in Target-Oriented Synthesis. Angew Chem Int Ed Engl 2019; 58:14055-14064. [PMID: 31162793 PMCID: PMC6764920 DOI: 10.1002/anie.201905532] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Indexed: 12/11/2022]
Abstract
Use of abundant feedstock pronucleophiles in catalytic carbonyl reductive coupling enhances efficiency in target-oriented synthesis. For such reactions, equally inexpensive reductants are desired or, ideally, corresponding hydrogen autotransfer processes may be enacted wherein alcohols serve dually as reductant and carbonyl proelectrophile. As described in this Minireview, these concepts allow reactions that traditionally require preformed organometallic reagents to be conducted catalytically in a byproduct-free manner from inexpensive π-unsaturated precursors.
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Affiliation(s)
- Rosalie S. Doerksen
- University of Texas at Austin, Department of Chemistry Welch Hall (A5300), 105 E 24 St., Austin, TX 78712, USA
| | - Cole C. Meyer
- University of Texas at Austin, Department of Chemistry Welch Hall (A5300), 105 E 24 St., Austin, TX 78712, USA
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry Welch Hall (A5300), 105 E 24 St., Austin, TX 78712, USA
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5
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Della-Felice F, Sarotti AM, Krische MJ, Pilli RA. Total Synthesis and Structural Validation of Phosdiecin A via Asymmetric Alcohol-Mediated Carbonyl Reductive Coupling. J Am Chem Soc 2019; 141:13778-13782. [PMID: 31433167 DOI: 10.1021/jacs.9b07512] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The first total synthesis and structural validation of phosdiecin A was accomplished in 13 steps through asymmetric iridium-catalyzed alcohol-mediated carbonyl reductive coupling. The present route is the shortest among >30 total and formal syntheses of fostriecin family members.
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Affiliation(s)
- Franco Della-Felice
- Institute of Chemistry , University of Campinas (UNICAMP) , P.O. Box 6154, CEP 13083-970 Campinas , São Paulo , Brazil.,Department of Chemistry , University of Texas at Austin , Austin , Texas 78712 , United States
| | - Ariel M Sarotti
- Instituto de Química Rosario, Facultad de Ciencias Bioquímicas y Farmacéuticas , Universidad Nacional de Rosario-CONICET , Suipacha 531, S2002LRK Rosario , Argentina
| | - Michael J Krische
- Department of Chemistry , University of Texas at Austin , Austin , Texas 78712 , United States
| | - Ronaldo A Pilli
- Institute of Chemistry , University of Campinas (UNICAMP) , P.O. Box 6154, CEP 13083-970 Campinas , São Paulo , Brazil
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6
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Cabrera JM, Krische MJ. Total Synthesis of Clavosolide A via Asymmetric Alcohol-Mediated Carbonyl Allylation: Beyond Protecting Groups or Chiral Auxiliaries in Polyketide Construction. Angew Chem Int Ed Engl 2019; 58:10718-10722. [PMID: 31166641 PMCID: PMC6656614 DOI: 10.1002/anie.201906259] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Indexed: 11/07/2022]
Abstract
The 20-membered marine macrodiolide clavosolide A is prepared in 7 steps (LLS) in the absence of protecting groups or chiral auxiliaries via enantioselective alcohol-mediated carbonyl addition. In 9 prior total syntheses, 11-34 steps (LLS) were required.
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Affiliation(s)
- James M. Cabrera
- University of Texas at Austin, Department of Chemistry 105 E 24th St. (A5300), Austin, TX 78712-1167 (USA)
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry 105 E 24th St. (A5300), Austin, TX 78712-1167 (USA)
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7
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Cabrera JM, Krische MJ. Total Synthesis of Clavosolide A via Asymmetric Alcohol‐Mediated Carbonyl Allylation: Beyond Protecting Groups or Chiral Auxiliaries in Polyketide Construction. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201906259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- James M. Cabrera
- University of Texas at AustinDepartment of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
| | - Michael J. Krische
- University of Texas at AustinDepartment of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
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8
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Doerksen RS, Meyer CC, Krische MJ. Feedstock Reagents in Metal‐Catalyzed Carbonyl Reductive Coupling: Minimizing Preactivation for Efficiency in Target‐Oriented Synthesis. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201905532] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Rosalie S. Doerksen
- University of Texas at Austin Department of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
| | - Cole C. Meyer
- University of Texas at Austin Department of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
| | - Michael J. Krische
- University of Texas at Austin Department of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
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10
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Pape F, Brechmann LT, Teichert JF. Catalytic Generation and Chemoselective Transfer of Nucleophilic Hydrides from Dihydrogen. Chemistry 2019; 25:985-988. [PMID: 30407666 DOI: 10.1002/chem.201805530] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Indexed: 11/06/2022]
Abstract
Copper(I)-N-heterocyclic-carbene (NHC) complexes enabled the catalytic generation of nucleophilic hydrides from dihydrogen (H2 ) and their subsequent transfer to allylic chlorides. The highly chemoselective catalyst displayed no concomitant hydrogenation reactivity; in fact, the terminal double bond formed in the hydride transfer remained intact. Switching to deuterium gas (D2 ) allowed for regioselective monodeuteration with excellent isotope incorporation.
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Affiliation(s)
- Felix Pape
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
| | - Lea T Brechmann
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
| | - Johannes F Teichert
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany
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11
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Tsai EY, Liu RY, Yang Y, Buchwald SL. A Regio- and Enantioselective CuH-Catalyzed Ketone Allylation with Terminal Allenes. J Am Chem Soc 2018; 140:2007-2011. [PMID: 29376366 PMCID: PMC5821421 DOI: 10.1021/jacs.7b12271] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We report a method for the highly enantioselective CuH-catalyzed allylation of ketones that employs terminal allenes as allylmetal surrogates. Ketones and allenes bearing diverse and sensitive functional groups are efficiently coupled with high stereoselectivity and exclusive branched regioselectivity. In stoichiometric experiments, each elementary step of the proposed hydrocupration-addition-metathesis mechanism can be followed by NMR spectroscopy.
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Affiliation(s)
- Erica Y. Tsai
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Richard Y. Liu
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Yang Yang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Stephen L. Buchwald
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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