601
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Song J, Chen DF, Gong LZ. Recent progress in organocatalytic asymmetric total syntheses of complex indole alkaloids. Natl Sci Rev 2017. [DOI: 10.1093/nsr/nwx028] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Abstract
Indole and its structural analogues have been frequently found in numerous alkaloids, pharmaceutical products and related materials. The enantioselective construction of these structures allows efficient total synthesis of optically pure indole alkaloids, and hence has received worldwide interest. In the past decade, asymmetric organocatalysis has been recognized as one of the most powerful strategies to create chiral molecules with high levels of stereoselectivity. In particular, organocatalytic asymmetric cascade reactions often occur with multiple bond-breaking and forming events simultaneously or sequentially, leading to the appearance of various straightforward approaches to access core structures for asymmetric total synthesis. This review will summarize recent applications of asymmetric organocatalysis in the enantioselective synthesis of indole alkaloids.
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Affiliation(s)
- Jin Song
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Dian-Feng Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Liu-Zhu Gong
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China
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602
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Bhat V, Welin ER, Guo X, Stoltz BM. Advances in Stereoconvergent Catalysis from 2005 to 2015: Transition-Metal-Mediated Stereoablative Reactions, Dynamic Kinetic Resolutions, and Dynamic Kinetic Asymmetric Transformations. Chem Rev 2017; 117:4528-4561. [PMID: 28164696 PMCID: PMC5516946 DOI: 10.1021/acs.chemrev.6b00731] [Citation(s) in RCA: 235] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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.
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Affiliation(s)
| | - Eric R. Welin
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | | | - Brian M. Stoltz
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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603
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Hou WY, Wu YK. Palladium-Catalyzed α-Arylation of Cyclic Vinylogous Esters for the Synthesis of γ-Arylcyclohexenones and Total Synthesis of Aromatic Podocarpane Diterpenoids. Org Lett 2017; 19:1220-1223. [DOI: 10.1021/acs.orglett.7b00268] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Wen-Yi Hou
- Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
| | - Yen-Ku Wu
- Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
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604
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Hojoh K, Ohmiya H, Sawamura M. Synthesis of α-Quaternary Formimides and Aldehydes through Umpolung Asymmetric Copper Catalysis with Isocyanides. J Am Chem Soc 2017; 139:2184-2187. [PMID: 28125781 DOI: 10.1021/jacs.6b12881] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A highly regio- and enantioselective copper-catalyzed three-component coupling of isocyanides, hydrosilanes, and γ,γ-disubstituted allylic phosphates/chlorides to afford chiral α-quaternary formimides was enabled by the combined use of our original chiral naphthol-carbene ligand as a functional Cu-supporting ligand and LiOtBu as a stoichiometric Lewis base for Si. The formimides were readily converted to α-quaternary aldehydes.
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Affiliation(s)
- Kentaro Hojoh
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan
| | - Hirohisa Ohmiya
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan
| | - Masaya Sawamura
- Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan
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605
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Singh S, Bruffaerts J, Vasseur A, Marek I. A unique Pd-catalysed Heck arylation as a remote trigger for cyclopropane selective ring-opening. Nat Commun 2017; 8:14200. [PMID: 28169276 PMCID: PMC5309700 DOI: 10.1038/ncomms14200] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 12/07/2016] [Indexed: 12/16/2022] Open
Abstract
Combining functionalization at a distant position from a reactive site with the creation of several consecutive stereogenic centres, including the formation of a quaternary carbon stereocentre, in acyclic system represents a pinnacle in organic synthesis. Here we report the regioselective Heck arylation of terminal olefins as a distant trigger for the ring-opening of cyclopropanes. This Pd-catalysed unfolding of the strained cycle, driving force of the chain-walking process, remarkably proved its efficiency and versatility, as the reaction proceeded regardless of the molecular distance between the initiation (double bond) and termination (alcohol) sites. Moreover, employing stereodefined polysubstituted cyclopropane vaults allowed to access sophisticated stereoenriched acyclic scaffolds in good yields. Conceptually, we demonstrated that merging catalytically a chain walking process with a selective C-C bond cleavage represents a powerful approach to construct linear skeleton possessing two stereogenic centres.
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Affiliation(s)
- Sukhdev Singh
- The Mallat Family Laboratory of Organic Chemistry, Schulich Faculty of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Jeffrey Bruffaerts
- The Mallat Family Laboratory of Organic Chemistry, Schulich Faculty of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Alexandre Vasseur
- The Mallat Family Laboratory of Organic Chemistry, Schulich Faculty of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Ilan Marek
- The Mallat Family Laboratory of Organic Chemistry, Schulich Faculty of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel
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606
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Zhao M, Chen J, Yang H, Zhou L. N-Heterocyclic Carbene-Catalyzed Intramolecular Nucleophilic Substitution: Enantioselective Construction of All-Carbon Quaternary Stereocenters. Chemistry 2017; 23:2783-2787. [DOI: 10.1002/chem.201700198] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Indexed: 01/04/2023]
Affiliation(s)
- Ming Zhao
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education; Department of Chemistry and Materials Science; Northwest University; Xi'an 710127 P. R. China
| | - Jie Chen
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education; Department of Chemistry and Materials Science; Northwest University; Xi'an 710127 P. R. China
| | - Hui Yang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education; Department of Chemistry and Materials Science; Northwest University; Xi'an 710127 P. R. China
| | - Ling Zhou
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education; Department of Chemistry and Materials Science; Northwest University; Xi'an 710127 P. R. China
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607
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Organocatalytic enantioselective Michael reaction of 1,3-dicarbonyls with α-substituted β-nitroacrylates. Tetrahedron 2017. [DOI: 10.1016/j.tet.2016.12.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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608
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Tang LW, Li C, Zhao BJ, Lan L, Zhang M, Zhou ZM. Diastereoselective construction of spirocyclic pyrrolidines bearing two quaternary centers via Cu II -P, N-Ligand catalyzed 1,3-dipolar cycloaddition. Tetrahedron 2017. [DOI: 10.1016/j.tet.2017.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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609
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Cruz FA, Dong VM. Stereodivergent Coupling of Aldehydes and Alkynes via Synergistic Catalysis Using Rh and Jacobsen's Amine. J Am Chem Soc 2017; 139:1029-1032. [PMID: 28074655 PMCID: PMC9141309 DOI: 10.1021/jacs.6b10680] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We report an enantioselective coupling between α-branched aldehydes and alkynes to generate vicinal quaternary and tertiary carbon stereocenters. The choice of Rh and organocatalyst combination allows for access to all possible stereoisomers with high enantio-, diastereo-, and regioselectivity. Our study highlights the power of catalysis to activate two common functional groups and provide access to divergent stereoisomers and constitutional structures.
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Affiliation(s)
- Faben A. Cruz
- Department of Chemistry, University of California, Irvine, California, 92697, United States
| | - Vy M. Dong
- Department of Chemistry, University of California, Irvine, California, 92697, United States
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610
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Sim JH, Song CE. Water-Enabled Catalytic Asymmetric Michael Reactions of Unreactive Nitroalkenes: One-Pot Synthesis of Chiral GABA-Analogs with All-Carbon Quaternary Stereogenic Centers. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611466] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jae Hun Sim
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
| | - Choong Eui Song
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
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611
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Sim JH, Song CE. Water-Enabled Catalytic Asymmetric Michael Reactions of Unreactive Nitroalkenes: One-Pot Synthesis of Chiral GABA-Analogs with All-Carbon Quaternary Stereogenic Centers. Angew Chem Int Ed Engl 2017; 56:1835-1839. [DOI: 10.1002/anie.201611466] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Jae Hun Sim
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
| | - Choong Eui Song
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
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612
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Kattela S, Heerdt G, Correia CRD. Non-Covalent Carbonyl-Directed Heck-Matsuda Desymmetrizations: Synthesis of Cyclopentene-Fused Spirooxindoles, Spirolactones, and Spirolactams. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201600946] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Shivashankar Kattela
- Institute of Chemistry; State University of Campinas; Campinas 13083-970, SP Brazil
| | - Gabriel Heerdt
- Institute of Chemistry; State University of Campinas; Campinas 13083-970, SP Brazil
| | - Carlos R. D. Correia
- Institute of Chemistry; State University of Campinas; Campinas 13083-970, SP Brazil
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613
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Yu K, Lu P, Jackson JJ, Nguyen TAD, Alvarado J, Stivala CE, Ma Y, Mack KA, Hayton TW, Collum DB, Zakarian A. Lithium Enolates in the Enantioselective Construction of Tetrasubstituted Carbon Centers with Chiral Lithium Amides as Noncovalent Stereodirecting Auxiliaries. J Am Chem Soc 2017; 139:527-533. [PMID: 27997174 PMCID: PMC6097510 DOI: 10.1021/jacs.6b11673] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lithium enolates derived from carboxylic acids are ubiquitous intermediates in organic synthesis. Asymmetric transformations with these intermediates, a central goal of organic synthesis, are typically carried out with covalently attached chiral auxiliaries. An alternative approach is to utilize chiral reagents that form discrete, well-defined aggregates with lithium enolates, providing a chiral environment conducive of asymmetric bond formation. These reagents effectively act as noncovalent, or traceless, chiral auxiliaries. Lithium amides are an obvious choice for such reagents as they are known to form mixed aggregates with lithium enolates. We demonstrate here that mixed aggregates can effect highly enantioselective transformations of lithium enolates in several classes of reactions, most notably in transformations forming tetrasubstituted and quaternary carbon centers. Easy recovery of the chiral reagent by aqueous extraction is another practical advantage of this one-step protocol. Crystallographic, spectroscopic, and computational studies of the central reactive aggregate, which provide insight into the origins of selectivity, are also reported.
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Affiliation(s)
- Kai Yu
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Ping Lu
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Jeffrey J Jackson
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Thuy-Ai D Nguyen
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Joseph Alvarado
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Craig E Stivala
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - Yun Ma
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Kyle A Mack
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Trevor W Hayton
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
| | - David B Collum
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
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614
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Wu Q, Li C, Wang W, Wang H, Pan D, Zheng P. NHC-catalyzed enantioselective synthesis of dihydropyran-4-carbonitriles bearing all-carbon quaternary centers. Org Chem Front 2017. [DOI: 10.1039/c7qo00571g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A LiCl assisted, carbene-catalyzed oxidative reaction for the synthesis of dihydropyran-4-carbonitriles bearing all-carbon quaternary centers was developed.
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Affiliation(s)
- Qiuju Wu
- Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering
- Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education
- Guizhou University
- Guiyang 550025
- China
| | - Chengcheng Li
- Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering
- Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education
- Guizhou University
- Guiyang 550025
- China
| | - Weihong Wang
- Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering
- Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education
- Guizhou University
- Guiyang 550025
- China
| | - Hongling Wang
- Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering
- Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education
- Guizhou University
- Guiyang 550025
- China
| | - Dingwu Pan
- Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering
- Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education
- Guizhou University
- Guiyang 550025
- China
| | - Pengcheng Zheng
- Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering
- Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education
- Guizhou University
- Guiyang 550025
- China
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615
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Wang M, Zhang X, Ling Z, Zhang Z, Zhang W. Direct enantioselective C-acylation for the construction of a quaternary stereocenter catalyzed by a chiral bicyclic imidazole. Chem Commun (Camb) 2017; 53:1381-1384. [DOI: 10.1039/c6cc09451a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A direct enantioselective C-acylation of benzofuranones was developed using a chiral bicyclic imidazole catalyst and an achiral tertiary amine additive.
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Affiliation(s)
- Mo Wang
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Xiao Zhang
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Zheng Ling
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Zhenfeng Zhang
- School of Pharmacy
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Wanbin Zhang
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
- School of Pharmacy
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616
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Huang HM, Bonilla P, Procter DJ. Selective construction of quaternary stereocentres in radical cyclisation cascades triggered by electron-transfer reduction of amide-type carbonyls. Org Biomol Chem 2017; 15:4159-4164. [DOI: 10.1039/c7ob00739f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Radical cyclisation cascades triggered by electron-transfer to amide-type carbonyls using SmI2–H2O–LiBr, result in the selective construction of quaternary carbon stereocentres.
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Affiliation(s)
| | - Pablo Bonilla
- School of Chemistry
- University of Manchester
- Manchester
- UK
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617
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Jiang Z, Hou L, Ni C, Chen J, Wang D, Tong X. Enantioselective construction of quaternary tetrahydropyridines by palladium-catalyzed vinylborylation of alkenes. Chem Commun (Camb) 2017; 53:4270-4273. [DOI: 10.1039/c7cc01488k] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The Pd(0)-catalyzed asymmetric vinylborylation of (Z)-1-iodo-dienes with B2pin2 is reported, which provides access to 3,3-disubstituted tetrahydropyridine with excellent enantioselectivity.
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Affiliation(s)
- Zhiwei Jiang
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals
- East China University of Science and Technology
- Shanghai
- China
| | - Longlei Hou
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
- China
| | - Chunjie Ni
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
- China
| | - Jiangfei Chen
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
- China
| | - Dong Wang
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology
- School of Petrochemical Engineering
- Changzhou University
- Changzhou
- China
| | - Xiaofeng Tong
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals
- East China University of Science and Technology
- Shanghai
- China
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology
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618
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Bos M, Riguet E. Iridium-catalysed asymmetric allylic alkylation of benzofuran γ-lactones followed by heteroaromatic Cope rearrangement: study of an unusual reaction sequence. Chem Commun (Camb) 2017; 53:4997-5000. [DOI: 10.1039/c7cc01529a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The iridium-catalysed asymmetric allylic alkylation of benzofuran γ-lactones produces 1,5-hexadienes that were found to be excellent substrates for an unusual heteroaromatic Cope rearrangement.
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Affiliation(s)
- Maxence Bos
- Université de Reims Champagne-Ardenne
- Institut de Chimie Moléculaire de Reims
- CNRS UMR 7312
- UFR des Sciences Exactes et Naturelles
- 51687 Reims Cedex 2
| | - Emmanuel Riguet
- Université de Reims Champagne-Ardenne
- Institut de Chimie Moléculaire de Reims
- CNRS UMR 7312
- UFR des Sciences Exactes et Naturelles
- 51687 Reims Cedex 2
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619
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Meng Q, Wang F. Mechanisms for nickel(0)/N-heterocyclic carbene-catalyzed intramolecular alkene hydroacylation: insights from a DFT study. J Mol Model 2016; 23:11. [PMID: 28004289 DOI: 10.1007/s00894-016-3186-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 12/06/2016] [Indexed: 10/20/2022]
Abstract
Density functional calculations have been applied to study and elucidate nickel(0)/N-heterocyclic carbene-catalyzed intramolecular alkene hydroacylation. The calculations showed that nickel(0)-catalyzed intramolecular alkene hydroacylation involved four potential reaction channels (I, II, III, and IV), and pathway IV was predicted to be more favorable than the other three. Two pathways, I and II, had three steps (oxidative addition, hydrogen migration, reductive elimination), and the rate-determining step was hydrogen migration. Pathway III proceeded through oxidative cyclization, β-hydride elimination, and hydrogen migration, and the rate-determining step was β-hydride elimination. Pathway IV included four steps (oxidative cyclization, dimerization, β-hydride elimination, hydrogen migration), and the rate-determining step was again β-hydride elimination. Oxidative cyclization was easy and led to rapid dimerization, greatly reducing the free energy of β-hydride elimination. The binuclear nickelacycle intermediate was observed in Ogoshi's experiments, and it was identified by nuclear magnetic resonance (NMR). The dominant product was the five-membered benzocyclic ketone p1. All results agreed with Ogoshi's experiments. Graphical Abstract Nickel(0)-catalyzed intramolecular alkene hydroacylation involved four potential reaction channels. The binuclear nickelacycle intermediate was important, and the dimerization greatly reduced the free energy of the β-hydride elimination.
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Affiliation(s)
- Qingxi Meng
- College of Chemistry and Material Science, Shandong Agricultural University, Taian, Shandong, 271018, People's Republic of China.
| | - Fen Wang
- Department of Chemistry, Taishan University, Taian, Shandong, 271021, People's Republic of China
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620
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Vaithiyanathan V, Kim MJ, Liu Y, Yan H, Song CE. Direct Access to Chiral β-Fluoroamines with Quaternary Stereogenic Center through Cooperative Cation-Binding Catalysis. Chemistry 2016; 23:1268-1272. [PMID: 27921333 DOI: 10.1002/chem.201605637] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Indexed: 01/28/2023]
Abstract
A direct route to chiral β-fluoroamines with tetrasubstituted C-F centers through the organocatalytic Mannich reaction of α-fluoro cyclic ketones and α-amidosulfones by using a chiral oligoethylene glycol as a cation-binding catalyst and KF as a base is reported. For most substrates, nearly perfect enantioselectivities were achieved even at very high temperatures (>80 °C). The salient features of this process include a) a transition-metal-free and operationally simple procedure, b) direct use of α-amidosulfones as bench-stable precursors of sensitive imines, c) direct enolization of racemic α-fluoro cyclic ketones, and d) excellent stereoselectivity up to 99 % enantiomeric excess and >20:1 diastereoselectivity (anti/syn). Thus, this protocol is easily scalable and provides a new approach for the synthesis of biologically relevant products with tetrasubstituted C-F centers. Furthermore, this protocol was also successfully extended to generate C-Cl and C-Br quaternary stereogenic centers.
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Affiliation(s)
| | - Mun Jong Kim
- Department of Chemistry, Sungkyunkwan University, Suwon, 440-746, Korea
| | - Yidong Liu
- Innovative Drug Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, 55 Daxuecheng South Rd., Chongqing, 401331, P.R. China
| | - Hailong Yan
- Innovative Drug Research Centre (IDRC), School of Pharmaceutical Sciences, Chongqing University, 55 Daxuecheng South Rd., Chongqing, 401331, P.R. China
| | - Choong Eui Song
- Department of Chemistry, Sungkyunkwan University, Suwon, 440-746, Korea
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621
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Nascimento de Oliveira M, Fournier J, Arseniyadis S, Cossy J. A Palladium-Catalyzed Asymmetric Allylic Alkylation Approach to α-Quaternary γ-Butyrolactones. Org Lett 2016; 19:14-17. [DOI: 10.1021/acs.orglett.6b02971] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Marllon Nascimento de Oliveira
- Laboratoire de
Chimie Organique,
Institute of Chemistry, Biology and Innovation (CBI) - ESPCI Paris/CNRS
(UMR8231), PSL Research University, 10 rue Vauquelin, 75231 Paris Cedex 05, France
| | - Jeremy Fournier
- Laboratoire de
Chimie Organique,
Institute of Chemistry, Biology and Innovation (CBI) - ESPCI Paris/CNRS
(UMR8231), PSL Research University, 10 rue Vauquelin, 75231 Paris Cedex 05, France
| | - Stellios Arseniyadis
- Laboratoire de
Chimie Organique,
Institute of Chemistry, Biology and Innovation (CBI) - ESPCI Paris/CNRS
(UMR8231), PSL Research University, 10 rue Vauquelin, 75231 Paris Cedex 05, France
| | - Janine Cossy
- Laboratoire de
Chimie Organique,
Institute of Chemistry, Biology and Innovation (CBI) - ESPCI Paris/CNRS
(UMR8231), PSL Research University, 10 rue Vauquelin, 75231 Paris Cedex 05, France
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622
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Jin H, Cho SM, Hwang GS, Ryu DH. Construction of 3,4-Dihydrocoumarin Derivatives with Adjacent Quaternary and Tertiary Stereocenters: Organocatalytic Asymmetric Michael Addition of 2-Oxochroman-3-carboxylate Esters totrans-β-Nitroolefins. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600825] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Hui Jin
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
| | - Soo Min Cho
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
| | - Geum-Sook Hwang
- Western Seoul Center; Korea Basic Science Institute; Seoul 120-140 Korea
| | - Do Hyun Ryu
- Department of Chemistry; Sungkyunkwan University; Suwon 440-746 Korea
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623
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De S, Das MK, Roy A, Bisai A. Synthesis of 2-Oxindoles Sharing Vicinal All-Carbon Quaternary Stereocenters via Organocatalytic Aldol Reaction. J Org Chem 2016; 81:12258-12274. [DOI: 10.1021/acs.joc.6b02195] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Subhadip De
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass
Road, Bhopal, MP 462 066, India
| | - Mrinal Kanti Das
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass
Road, Bhopal, MP 462 066, India
| | - Avishek Roy
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass
Road, Bhopal, MP 462 066, India
| | - Alakesh Bisai
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass
Road, Bhopal, MP 462 066, India
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624
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Hethcox JC, Shockley SE, Stoltz BM. Iridium-Catalyzed Stereoselective Allylic Alkylation Reactions with Crotyl Chloride. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201609960] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- J. Caleb Hethcox
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering; California Institute of Technology; 1200 E. California Blvd, MC 101-20 Pasadena CA 91125 USA
| | - Samantha E. Shockley
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering; California Institute of Technology; 1200 E. California Blvd, MC 101-20 Pasadena CA 91125 USA
| | - Brian M. Stoltz
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering; California Institute of Technology; 1200 E. California Blvd, MC 101-20 Pasadena CA 91125 USA
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625
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Hethcox JC, Shockley SE, Stoltz BM. Iridium-Catalyzed Stereoselective Allylic Alkylation Reactions with Crotyl Chloride. Angew Chem Int Ed Engl 2016; 55:16092-16095. [PMID: 27891825 DOI: 10.1002/anie.201609960] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 10/27/2016] [Indexed: 11/09/2022]
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.
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Affiliation(s)
- J Caleb Hethcox
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, MC 101-20, Pasadena, CA, 91125, USA
| | - Samantha E Shockley
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, MC 101-20, Pasadena, CA, 91125, USA
| | - Brian M Stoltz
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, MC 101-20, Pasadena, CA, 91125, USA
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626
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Dange NS, Robert F, Landais Y. Free-Radical Carbocyanation of Cyclopropenes: Stereocontrolled Access to All-Carbon Quaternary Stereocenters in Acyclic Systems. Org Lett 2016; 18:6156-6159. [DOI: 10.1021/acs.orglett.6b03163] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nitin S. Dange
- University of Bordeaux, Institute of Molecular Sciences, UMR-CNRS 5255, 351 cours de la libération, 33405 Talence, France
| | - Frédéric Robert
- University of Bordeaux, Institute of Molecular Sciences, UMR-CNRS 5255, 351 cours de la libération, 33405 Talence, France
| | - Yannick Landais
- University of Bordeaux, Institute of Molecular Sciences, UMR-CNRS 5255, 351 cours de la libération, 33405 Talence, France
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627
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Wright TB, Evans PA. Enantioselective Rhodium-Catalyzed Allylic Alkylation of Prochiral α,α-Disubstituted Aldehyde Enolates for the Construction of Acyclic Quaternary Stereogenic Centers. J Am Chem Soc 2016; 138:15303-15306. [DOI: 10.1021/jacs.6b10099] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Timothy B. Wright
- Department
of Chemistry Queen’s University, 90 Bader Lane, Kingston, Ontario K7L
3N6, Canada
| | - P. Andrew Evans
- Department
of Chemistry Queen’s University, 90 Bader Lane, Kingston, Ontario K7L
3N6, Canada
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628
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Kesava-Reddy N, Golz C, Strohmann C, Kumar K. Silver(I)-Catalyzed Enantioselective [3+2]-Cycloaddition Reaction of α-Silylimines: A Facile Route to Quaternary-Carbon-Rich Scaffolds. Chemistry 2016; 22:18373-18377. [DOI: 10.1002/chem.201604793] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Naredla Kesava-Reddy
- Abteilung Chemische Biologie; Max-Planck-Institut für Molekulare Physiologie; Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Christopher Golz
- Fakultät Chemie und Chemische Biologie; Technische Universität Dortmund; Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Carsten Strohmann
- Fakultät Chemie und Chemische Biologie; Technische Universität Dortmund; Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Kamal Kumar
- Abteilung Chemische Biologie; Max-Planck-Institut für Molekulare Physiologie; Otto-Hahn-Straße 11 44227 Dortmund Germany
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629
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Nguyen KD, Herkommer D, Krische MJ. Enantioselective Formation of All-Carbon Quaternary Centers via C-H Functionalization of Methanol: Iridium-Catalyzed Diene Hydrohydroxymethylation. J Am Chem Soc 2016; 138:14210-14213. [PMID: 27762549 PMCID: PMC5094804 DOI: 10.1021/jacs.6b09333] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The first catalytic enantioselective C-C couplings of methanol (>30 × 106 tons/year) are reported. Insertion of 2-substituted dienes into the methanol C-H bond occurs in a regioselective manner to form all-carbon quaternary centers with excellent levels of enantioselectivity using an iridium-PhanePhos catalyst. Mechanistic studies corroborate a Curtin-Hammett scenario in which methanol dehydrogenation triggers rapid, reversible diene hydrometalation en route to regioisomeric allyliridium-formaldehyde pairs, yet single constitutional isomers are formed.
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Affiliation(s)
- Khoa D. Nguyen
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Daniel Herkommer
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
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630
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Berkes B, Ozsváth K, Molnár L, Gáti T, Holczbauer T, Kardos G, Soós T. Expedient and Diastereodivergent Assembly of Terpenoid Decalin Subunits having Quaternary Stereocenters through Organocatalytic Robinson Annulation of Nazarov Reagent. Chemistry 2016; 22:18101-18106. [DOI: 10.1002/chem.201604541] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Barbara Berkes
- Institute of Organic Chemistry; Hungarian Academy of Sciences; 1519 Budapest, P.O. Box 286 Hungary
| | - Kristóf Ozsváth
- Institute of Organic Chemistry; Hungarian Academy of Sciences; 1519 Budapest, P.O. Box 286 Hungary
| | - Laura Molnár
- Institute of Organic Chemistry; Hungarian Academy of Sciences; 1519 Budapest, P.O. Box 286 Hungary
| | - Tamás Gáti
- Servier Research Institute of Medicinal Chemistry; Záhony Street 7 1031 Budapest Hungary
| | - Tamás Holczbauer
- Institute of Organic Chemistry; Hungarian Academy of Sciences; 1519 Budapest, P.O. Box 286 Hungary
| | - György Kardos
- Institute of Organic Chemistry; Hungarian Academy of Sciences; 1519 Budapest, P.O. Box 286 Hungary
| | - Tibor Soós
- Institute of Organic Chemistry; Hungarian Academy of Sciences; 1519 Budapest, P.O. Box 286 Hungary
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631
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Patel HH, Sigman MS. Enantioselective Palladium-Catalyzed Alkenylation of Trisubstituted Alkenols To Form Allylic Quaternary Centers. J Am Chem Soc 2016; 138:14226-14229. [PMID: 27768842 DOI: 10.1021/jacs.6b09649] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this report, we describe the generation of remote allylic quaternary stereocenters β, γ, and δ relative to a carbonyl in high enantioselectivity. We utilize a redox-relay Heck reaction between alkenyl triflates and acyclic trisubstituted alkenols of varying chain-lengths. A wide array of terminal (E)-alkenyl triflates are suitable for this process. The utility of this functionalization is validated further by conversion of the products, via simple organic processes to access remotely functionalized chiral tertiary acid, amine, and alcohol products.
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Affiliation(s)
- Harshkumar H Patel
- Department of Chemistry, University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Matthew S Sigman
- Department of Chemistry, University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112, United States
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632
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Lin HC, Wang PS, Tao ZL, Chen YG, Han ZY, Gong LZ. Highly Enantioselective Allylic C–H Alkylation of Terminal Olefins with Pyrazol-5-ones Enabled by Cooperative Catalysis of Palladium Complex and Brønsted Acid. J Am Chem Soc 2016; 138:14354-14361. [DOI: 10.1021/jacs.6b08236] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Hua-Chen Lin
- Hefei National
Laboratory for Physical Sciences at the Microscale, and Department
of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Pu-Sheng Wang
- Hefei National
Laboratory for Physical Sciences at the Microscale, and Department
of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Zhong-Lin Tao
- Hefei National
Laboratory for Physical Sciences at the Microscale, and Department
of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Yu-Gen Chen
- Hefei National
Laboratory for Physical Sciences at the Microscale, and Department
of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Zhi-Yong Han
- Hefei National
Laboratory for Physical Sciences at the Microscale, and Department
of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Liu-Zhu Gong
- Hefei National
Laboratory for Physical Sciences at the Microscale, and Department
of Chemistry, University of Science and Technology of China, Hefei, 230026, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
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633
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Xu W, Shen X, Ma Q, Gong L, Meggers E. Restricted Conformation of a Hydrogen Bond Mediated Catalyst Enables the Highly Efficient Enantioselective Construction of an All-Carbon Quaternary Stereocenter. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02080] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Weici Xu
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Xiang Shen
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Qiao Ma
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Lei Gong
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Eric Meggers
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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634
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Ling T, Rivas F. All-carbon quaternary centers in natural products and medicinal chemistry: recent advances. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.09.002] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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635
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Liu Y, Hu H, Lin L, Hao X, Liu X, Feng X. Enantioselective construction of branched 1,3-dienyl substituted quaternary carbon stereocenters by asymmetric allenyl Claisen rearrangement. Chem Commun (Camb) 2016; 52:11963-11966. [PMID: 27711320 DOI: 10.1039/c6cc06481g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The availability of enantiomerically enriched 1,3-dienyl substituted quaternary stereocenters is highly valuable for the synthesis of complex natural compounds. Despite great advances in the area of construction of alkenyl-substituted types, a general, practical catalytic system that works for enantioselective formation of 1,3-diene derivatives still remains to be developed. Herein, we disclose the first asymmetric Claisen rearrangement of allenyl vinyl ethers to access optically active β-ketoesters, containing branched 1,3-butadienyl substituted stereocenters. A variety of substrates bearing a range of useful functional groups were well tolerated, thus affording the corresponding products with excellent enantioselectivities (up to 99% ee) and high yields (up to 91%).
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Affiliation(s)
- Yangbin Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Haipeng Hu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Lili Lin
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Xiaoyu Hao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China. and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), China
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636
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Seguin TJ, Wheeler SE. Competing Noncovalent Interactions Control the Stereoselectivity of Chiral Phosphoric Acid Catalyzed Ring Openings of 3-Substituted Oxetanes. ACS Catal 2016. [DOI: 10.1021/acscatal.6b01915] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Trevor J. Seguin
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Steven E. Wheeler
- Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States
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637
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Nairoukh Z, Kumar GGKSN, Minko Y, Marek I. Enantioselective allylic alkylation of stereodefined polysubstituted copper enolates as an entry to acyclic quaternary carbon stereocentres. Chem Sci 2016; 8:627-630. [PMID: 28451210 PMCID: PMC5358538 DOI: 10.1039/c6sc03036j] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 08/25/2016] [Indexed: 01/09/2023] Open
Abstract
A sequence of regio- and stereoselective carbometalation followed by oxidation of ynamides leads to stereodefined fully substituted enolates that subsequently react with various functionalized allyl bromide reagents to provide the enantiomerically pure quaternary carbon stereocentre in the α-position to the carbonyl group.
A sequence of regio- and stereoselective carbometalation followed by oxidation of ynamides leads to stereodefined fully substituted enolates that subsequently react with various functionalized allyl bromide reagents to provide the expected products possessing an enantiomerically pure quaternary carbon stereocentre in the α-position to the carbonyl group in excellent yields and enantiomeric ratios after cleavage of the oxazolidinone moiety. Three new bonds are formed in a single-pot operation.
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Affiliation(s)
- Zackaria Nairoukh
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
| | - Gunda G K S Narayana Kumar
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
| | - Yury Minko
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
| | - Ilan Marek
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
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638
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Xiong Y, Zhang G. Enantioselective Synthesis of Quaternary Stereocenters via Chromium Catalysis. Org Lett 2016; 18:5094-5097. [DOI: 10.1021/acs.orglett.6b02540] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Yang Xiong
- State Key Laboratory of Organometallic
Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Guozhu Zhang
- State Key Laboratory of Organometallic
Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
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639
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640
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Hayashi Y, Bondzic BP, Yamazaki T, Gupta Y, Ogasawara S, Taniguchi T, Monde K. Asymmetric Diels-Alder Reaction of α-Substituted and β,β-Disubstituted α,β-Enals via Diarylprolinol Silyl Ether for the Construction of All-Carbon Quaternary Stereocenters. Chemistry 2016; 22:15874-15880. [PMID: 27601216 DOI: 10.1002/chem.201602345] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Indexed: 11/11/2022]
Abstract
The asymmetric Diels-Alder reaction of α-substituted acrolein proceeds in the presence of the trifluoroacetic acid salt of trifluoromethyl-substituted diarylprolinol silyl ether to afford the exo-isomer with both excellent diastereoselectivity and high enantioselectivity. In the Diels-Alder reaction of a β,β-disubstituted α,β-unsaturated aldehyde, good exo-selectivity and excellent enantioselectivity was obtained when the perchloric acid salt of the bulky triisopropyl silyl ether of trifluoromethyl substituted diarylprolinol was employed as an organocatalyst in the presence of water. In both cases, all-carbon quaternary stereocenters are constructed enantioselectively.
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Affiliation(s)
- Yujiro Hayashi
- Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai, 980-8578, Japan. .,Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.
| | - Bojan P Bondzic
- Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Tatsuya Yamazaki
- Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Yogesh Gupta
- Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai, 980-8578, Japan
| | - Shin Ogasawara
- Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai, 980-8578, Japan
| | - Tohru Taniguchi
- Faculty of Advanced Life Science, Frontier Research Center for Advanced Material and Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo, 001-0021, Japan
| | - Kenji Monde
- Faculty of Advanced Life Science, Frontier Research Center for Advanced Material and Life Science, Hokkaido University, Kita 21 Nishi 11, Sapporo, 001-0021, Japan
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641
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Guduguntla S, Gualtierotti JB, Goh SS, Feringa BL. Enantioselective Synthesis of Di- and Tri-Arylated All-Carbon Quaternary Stereocenters via Copper-Catalyzed Allylic Arylations with Organolithium Compounds. ACS Catal 2016. [DOI: 10.1021/acscatal.6b01681] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Sureshbabu Guduguntla
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747
AG Groningen, The Netherlands
| | - Jean-Baptiste Gualtierotti
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747
AG Groningen, The Netherlands
| | - Shermin S. Goh
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747
AG Groningen, The Netherlands
| | - Ben L. Feringa
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747
AG Groningen, The Netherlands
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642
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Gao Z, Fletcher SP. Acyclic quaternary centers from asymmetric conjugate addition of alkylzirconium reagents to linear trisubstituted enones. Chem Sci 2016; 8:641-646. [PMID: 28451211 PMCID: PMC5358539 DOI: 10.1039/c6sc02811j] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/01/2016] [Indexed: 11/21/2022] Open
Abstract
Synthetic methods for the selective formation of all carbon quaternary centres in non-cyclic systems are rare. Here we report highly enantioselective Cu-catalytic asymmetric conjugate addition of alkylzirconium species to twelve different acyclic trisubstituted enones.
Synthetic methods for the selective formation of all carbon quaternary centres in non-cyclic systems are rare. Here we report highly enantioselective Cu-catalytic asymmetric conjugate addition of alkylzirconium species to twelve different acyclic trisubstituted enones. A variety of sp3-hybridized nucleophiles generated by in situ hydrozirconation of alkenes with the Schwartz reagent can be introduced, giving linear products bearing quaternary centres with up to 98% ee. The method is tolerant of several important functional groups and 27 total examples are reported. The method uses a new chiral nonracemic phosphoramidite ligand in a complex with copper triflate as the catalyst. This work allows the straightforward stereocontrolled formation of a valuable structural motif using only a catalytic amount of chiral reagent.
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Affiliation(s)
- Zhenbo Gao
- Department of Chemistry , University of Oxford. Chemistry Research Laboratory , 12 Mansfield Road , Oxford , OX1 3TA , UK .
| | - Stephen P Fletcher
- Department of Chemistry , University of Oxford. Chemistry Research Laboratory , 12 Mansfield Road , Oxford , OX1 3TA , UK .
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643
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Roy SR, Didier D, Kleiner A, Marek I. Diastereodivergent combined carbometalation/zinc homologation/C-C fragmentation reaction as an efficient tool to prepare acyclic allylic quaternary carbon stereocenters. Chem Sci 2016; 7:5989-5994. [PMID: 30034740 PMCID: PMC6022242 DOI: 10.1039/c6sc02191c] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 05/23/2016] [Indexed: 02/05/2023] Open
Abstract
A new strategy has been developed to construct enantiomerically enriched acyclic allylic quaternary carbon stereocenters in a single-pot operation through a combined carbometalation/zinc homologation/fragmentation sequence. Proper tuning of the reaction conditions enables the synthesis of the two enantiomers starting from a single enantiomer of the starting material.
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Affiliation(s)
- Sudipta Raha Roy
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
| | - Dorian Didier
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
| | - Amir Kleiner
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
| | - Ilan Marek
- The Mallat Family Laboratory of Organic Chemistry , Schulich Faculty of Chemistry and Lise Meitner-Minerva Center for Computational Quantum Chemistry , Technion-Israel Institute of Technology , Technion City , Haifa 32000 , Israel . ; ; Tel: +972-4-829-37-09
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644
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Stereoselective construction of all-carbon quaternary stereocenters by allylboration of chiral aldehydes: synthesis of a fragment of (+)-vibsanin A. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.07.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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645
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Tang LW, Zhao BJ, Dai L, Zhang M, Zhou ZM. Asymmetric Construction of Pyrrolidines Bearing a Trifluoromethylated Quaternary Stereogenic Center via CuI
-Catalyzed 1,3-Dipolar Cycloaddition of Azomethine Ylides with β-CF3
-β,β-Disubstituted Nitroalkenes. Chem Asian J 2016; 11:2470-7. [DOI: 10.1002/asia.201600941] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Li-Wei Tang
- R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment; Beijing Institute of Technology; 5th Zhongguancun South Street, Haidian District Beijing China
| | - Bao-Jing Zhao
- R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment; Beijing Institute of Technology; 5th Zhongguancun South Street, Haidian District Beijing China
| | - Li Dai
- R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment; Beijing Institute of Technology; 5th Zhongguancun South Street, Haidian District Beijing China
| | - Man Zhang
- R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment; Beijing Institute of Technology; 5th Zhongguancun South Street, Haidian District Beijing China
| | - Zhi-Ming Zhou
- R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment; Beijing Institute of Technology; 5th Zhongguancun South Street, Haidian District Beijing China
- State Key Laboratory of Explosion Science and Technology; Beijing Institute of Technology; 5th Zhongguancun South Street, Haidian District Beijing China
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646
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Mo X, Hall DG. Dual Catalysis Using Boronic Acid and Chiral Amine: Acyclic Quaternary Carbons via Enantioselective Alkylation of Branched Aldehydes with Allylic Alcohols. J Am Chem Soc 2016; 138:10762-5. [DOI: 10.1021/jacs.6b06101] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xiaobin Mo
- Department
of Chemistry,
Centennial Centre for Interdisciplinary Science, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Dennis G. Hall
- Department
of Chemistry,
Centennial Centre for Interdisciplinary Science, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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647
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Jamison CR, Overman LE. Fragment Coupling with Tertiary Radicals Generated by Visible-Light Photocatalysis. Acc Chem Res 2016; 49:1578-86. [PMID: 27491019 DOI: 10.1021/acs.accounts.6b00284] [Citation(s) in RCA: 152] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Convergent synthesis strategies in which a target molecule is prepared by a branched approach wherein two or more complex fragments are combined at a late stage are almost always preferred over a linear approach in which the overall yield of the target molecule is eroded by the efficiency of each successive step in the sequence. As a result, bimolecular reactions that are able to combine complex fragments in good yield and, where important, with high stereocontrol are essential for implementing convergent synthetic strategies. Although intramolecular reactions of carbon radicals have long been exploited to assemble polycyclic ring systems, bimolecular coupling reactions of structurally complex carbon radicals have rarely been employed to combine elaborate fragments in the synthesis of structurally intricate molecules. We highlight in this Account recent discoveries from our laboratories that demonstrate that bimolecular reactions of structurally elaborate tertiary carbon radicals and electron-deficient alkenes can unite complex fragments in high yield using nearly equimolar amounts of the two coupling partners. Our discussion begins by considering several aspects of the bimolecular addition of tertiary carbon radicals to electron-deficient alkenes that commend these transformations for the union of structurally complex, sterically bulky fragments. We then discuss how in the context of synthesizing rearranged spongian diterpenoids we became aware of the exceptional utility of coupling reactions of alkenes and tertiary carbon radicals to unite structurally complex synthetic intermediates. Our initial investigations exploit the early report of Okada that N-(acyloxy)phthalimides reductively fragment at room temperature in the presence of visible light and catalytic amounts of the photocatalyst Ru(bpy)3Cl2 to form carbon radicals that react with alkenes. We show that this reaction of a tertiary radical precursor and an enone can combine two elaborate enantioenriched fragments in good yield with the formation of new quaternary and secondary stereocenters. As a result of the ready availability of tertiary alcohols, we describe two methods that were developed, one in collaboration with the MacMillan group, to generate tertiary radicals from tertiary alcohols. In the method that will be preferred in most instances, the tertiary alcohol is esterified in high yield to give a tert-alkyl hemioxalate salt, which-without purification-reacts with electron-deficient alkenes in the presence of visible light and an Ir(III) photocatalyst to give coupled products having a newly formed quaternary carbon in high yield. Hemioxalate salts containing Li, Na, K, and Cs countercations can be employed in this reaction, whose only other product is CO2. These reactions are carried out using nearly equimolar amounts of the addends, making them ideal for coupling of complex fragments at the late stage in a synthetic sequence. The attractive attributes of the fragment-coupling chemistry that we discuss in this Account are illustrated by an enantioselective total synthesis of a tricyclic trans-clerodane diterpenoid in eight steps and 34% overall yield from commercially available precursors. We anticipate that bimolecular reactions of carbon radicals will be increasingly used for fragment coupling in the future.
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Affiliation(s)
- Christopher R. Jamison
- Department
of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Larry E. Overman
- Department
of Chemistry, University of California, Irvine, California 92697-2025, United States
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648
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Chen S, Wu XX, Wang J, Hao XH, Xia Y, Shen Y, Jing H, Liang YM. Palladium-Catalyzed Intramolecular Dearomatization of Indoles via Decarboxylative Alkynyl Termination. Org Lett 2016; 18:4016-9. [DOI: 10.1021/acs.orglett.6b01711] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Si Chen
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Xin-Xing Wu
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Jia Wang
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Xin-Hua Hao
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Yu Xia
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Yi Shen
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Huanwang Jing
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
| | - Yong-Min Liang
- State Key Laboratory of Applied
Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
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649
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Catalytic enantioselective 1,6-conjugate additions of propargyl and allyl groups. Nature 2016; 537:387-393. [PMID: 27479320 PMCID: PMC5161616 DOI: 10.1038/nature19063] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/21/2016] [Indexed: 12/22/2022]
Abstract
Conjugate (or 1,4-) additions of carbanionic species to α,β-unsaturated carbonyl compounds are vital to research in organic and medicinal chemistry, and there are several chiral catalysts that facilitate the catalytic enantioselective additions of nucleophiles to enoates. Nonetheless, catalytic enantioselective 1,6-conjugate additions are uncommon, and ones that incorporate readily functionalizable moieties, such as propargyl or allyl groups, into acyclic α,β,γ,δ-doubly unsaturated acceptors are unknown. Chemical transformations that could generate a new bond at the C6 position of a dienoate are particularly desirable because the resulting products could then be subjected to further modifications. However, such reactions, especially when dienoates contain two equally substituted olefins, are scarce and are confined to reactions promoted by a phosphine-copper catalyst (with an alkyl Grignard reagent, dialkylzinc or trialkylaluminium compounds), a diene-iridium catalyst (with arylboroxines), or a bisphosphine-cobalt catalyst (with monosilyl-acetylenes). 1,6-Conjugate additions are otherwise limited to substrates where there is full substitution at the C4 position. It is unclear why certain catalysts favour bond formation at C6, and-although there are a small number of catalytic enantioselective conjugate allyl additions-related 1,6-additions and processes involving a propargyl unit are non-existent. Here we show that an easily accessible organocopper catalyst can promote 1,6-conjugate additions of propargyl and 2-boryl-substituted allyl groups to acyclic dienoates with high selectivity. A commercially available allenyl-boron compound or a monosubstituted allene may be used. Products can be obtained in up to 83 per cent yield, >98:2 diastereomeric ratio (for allyl additions) and 99:1 enantiomeric ratio. We elucidate the mechanistic details, including the origins of high site selectivity (1,6- versus 1,4-) and enantioselectivity as a function of the catalyst structure and reaction type, by means of density functional theory calculations. The utility of the approach is highlighted by an application towards enantioselective synthesis of the anti-HIV agent (-)-equisetin.
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650
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Das D, Chakraborty TK. An overview of the recent synthetic studies toward penifulvins and other fenestranes. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2016.07.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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