551
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Diastereo- and enantioselective [3 + 3] cycloaddition of spirocyclopropyl oxindoles using both aldonitrones and ketonitrones. Nat Commun 2017; 8:1619. [PMID: 29158496 PMCID: PMC5696380 DOI: 10.1038/s41467-017-01451-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 09/18/2017] [Indexed: 02/02/2023] Open
Abstract
Optically active spirocyclic compounds play an important role in drug discovery, and new synthetic strategies for the efficient generation of spiro stereocenters are in much demand. Here we report a catalytic enantioselective cycloaddition using spirocyclic donor–acceptor cyclopropanes as a promising approach for the generation of spiro stereocenters. A diastereo- and enantioselective [3 + 3] cycloaddition of spirocyclopropyl oxindoles with both aldonitrones and ketonitrones is developed. The key to reaction development is the activation of spirocyclopropyl oxindoles by a suitable electron-withdrawing N-protecting group. This activation approach offers the promise of a general solution to enable spirocyclopropyl oxindoles as synthons for catalytic enantioselective synthesis of spirocyclic oxindoles featuring a C3 spiro stereocenter, a prominent structural motif in drugs and pharmaceutically active compounds. This protocol also constitutes the catalytic enantioselective reaction using unactivated achiral ketonitrones to construct tetrasubstituted carbon stereocenters. Chiral spirocyclic compounds are important structural motifs for drug discovery. Here, the authors report a synthetic route to spirocycles based on enantioselective cycloaddition of activated spirocyclopropyl oxindoles, which act as donor-acceptor cyclopropanes.
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552
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Bora PP, Sun GJ, Zheng WF, Kang Q. Rh/Lewis Acid Catalyzed Regio-, Diastereo- and Enantioselective Addition of 2-Acyl Imidazoles with Allenes. CHINESE J CHEM 2017. [DOI: 10.1002/cjoc.201700596] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Pranjal P. Bora
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology; Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences; 155 Yangqiao Road West, Fuzhou Fujian 350002 China
| | - Gui-Jun Sun
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology; Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences; 155 Yangqiao Road West, Fuzhou Fujian 350002 China
| | - Wei-Feng Zheng
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology; Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences; 155 Yangqiao Road West, Fuzhou Fujian 350002 China
| | - Qiang Kang
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology; Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences; 155 Yangqiao Road West, Fuzhou Fujian 350002 China
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553
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Garnsey MR, Slutskyy Y, Jamison CR, Zhao P, Lee J, Rhee YH, Overman LE. Short Enantioselective Total Syntheses of Cheloviolenes A and B and Dendrillolide C via Convergent Fragment Coupling Using a Tertiary Carbon Radical. J Org Chem 2017; 83:6958-6976. [DOI: 10.1021/acs.joc.7b02458] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Michelle R. Garnsey
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Yuriy Slutskyy
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Christopher R. Jamison
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Peng Zhao
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Juyeol Lee
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Young Ho Rhee
- Department of Chemistry, Pohang University of Science and Technology, Hyoja-dong San 31, Pohang, Kyungbook 790-784, Republic of Korea
| | - Larry E. Overman
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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554
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Yoshida M. Asymmetric α-Allylation of α-Substituted β-Ketoesters with Allyl Alcohols. J Org Chem 2017; 82:12821-12826. [DOI: 10.1021/acs.joc.7b02188] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Masanori Yoshida
- Faculty of Mathematics and Science, National Institute of Technology, Asahikawa College, Shunkodai 2 jo 2-1-6, Asahikawa, Hokkaido 071-8142, Japan
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555
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Feng J, Holmes M, Krische MJ. Acyclic Quaternary Carbon Stereocenters via Enantioselective Transition Metal Catalysis. Chem Rev 2017; 117:12564-12580. [PMID: 28910092 PMCID: PMC5651685 DOI: 10.1021/acs.chemrev.7b00385] [Citation(s) in RCA: 306] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Whereas numerous asymmetric methods for formation of quaternary carbon stereocenters in cyclic systems have been documented, the construction of acyclic quaternary carbon stereocenters with control of absolute stereochemistry remains a formidable challenge. This Review summarizes enantioselective methods for the construction of acyclic quaternary carbon stereocenters from achiral or chiral racemic reactants via transition metal catalysis.
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Affiliation(s)
- Jiajie Feng
- Department of Chemistry, Welch Hall (A5300), University of Texas at Austin , 105 East 24th Street, Austin, Texas 78712, United States
| | - Michael Holmes
- Department of Chemistry, Welch Hall (A5300), University of Texas at Austin , 105 East 24th Street, Austin, Texas 78712, United States
| | - Michael J Krische
- Department of Chemistry, Welch Hall (A5300), University of Texas at Austin , 105 East 24th Street, Austin, Texas 78712, United States
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556
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Li MM, Wei Y, Liu J, Chen HW, Lu LQ, Xiao WJ. Sequential Visible-Light Photoactivation and Palladium Catalysis Enabling Enantioselective [4+2] Cycloadditions. J Am Chem Soc 2017; 139:14707-14713. [DOI: 10.1021/jacs.7b08310] [Citation(s) in RCA: 160] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Miao-Miao Li
- Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People’s Republic of China
| | - Yi Wei
- Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People’s Republic of China
| | - Jie Liu
- Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People’s Republic of China
| | - Hong-Wei Chen
- Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People’s Republic of China
| | - Liang-Qiu Lu
- Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People’s Republic of China
- State Key Laboratory for Oxo Synthesis and Selective
Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China
| | - Wen-Jing Xiao
- Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, People’s Republic of China
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557
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Wu Z, Wang J. Enantioselective Medium-Ring Lactone Synthesis through an NHC-Catalyzed Intramolecular Desymmetrization of Prochiral 1,3-Diols. ACS Catal 2017. [DOI: 10.1021/acscatal.7b02302] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Zijun Wu
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Jian Wang
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
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558
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Liniger M, Liu Y, Stoltz BM. Sequential Ruthenium Catalysis for Olefin Isomerization and Oxidation: Application to the Synthesis of Unusual Amino Acids. J Am Chem Soc 2017; 139:13944-13949. [PMID: 28918631 PMCID: PMC5628162 DOI: 10.1021/jacs.7b08496] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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 α-tri- and tetrasubstituted α-amino acids including an expedient total synthesis of the antiepileptic drug levetiracetam.
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Affiliation(s)
| | - Yiyang Liu
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Brian M. Stoltz
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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559
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Shemet A, Carreira EM. Total Synthesis of (−)-Rhazinilam and Formal Synthesis of (+)-Eburenine and (+)-Aspidospermidine: Asymmetric Cu-Catalyzed Propargylic Substitution. Org Lett 2017; 19:5529-5532. [DOI: 10.1021/acs.orglett.7b02619] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andrej Shemet
- ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
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560
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Sawa M, Morisaki K, Kondo Y, Morimoto H, Ohshima T. Direct Access to N-Unprotected α- and/or β-Tetrasubstituted Amino Acid Esters via Direct Catalytic Mannich-Type Reactions Using N-Unprotected Trifluoromethyl Ketimines. Chemistry 2017; 23:17022-17028. [PMID: 28950035 DOI: 10.1002/chem.201703516] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Indexed: 11/08/2022]
Abstract
Direct catalytic C-C bond-forming addition to N-unprotected ketimines is an efficient and straightforward method of synthesizing N-unprotected tetrasubstituted amines that eliminates prior protection/deprotection steps and allows facile transformation of the products. Despite its advantages, however, N-unprotected ketimines have difficulties in C-C bond-forming reactions, and only a limited number of reactions and substrates are reported compared with their N-protected counterparts. Herein we report that N-unprotected trifluoromethyl ketimines are effective for C-C bond-forming reactions using Mannich-type reactions as a model case. We demonstrate that Lewis acid catalysis was effective for promoting reactions with various N-unprotected trifluoromethyl ketimines, and thiourea organocatalysis was effective for promoting highly enantioselective reactions with various carbonyl nucleophiles, providing direct access to various N-unprotected α- and/or β-tetrasubstituted amino acid esters. Furthermore, direct construction of vicinal tetrasubstituted chiral carbon stereocenters was achieved for the first time in a highly enantio- and diastereoselective manner. These results demonstrate the potential of N-unprotected ketimines as substrates applicable to many other addition reactions.
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Affiliation(s)
- Masanao Sawa
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Kazuhiro Morisaki
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
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561
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Huang B, Li C, Wang H, Wang C, Liu L, Zhang J. Phosphine-Catalyzed Diastereo- and Enantioselective Michael Addition of β-Carbonyl Esters to β-Trifluoromethyl and β-Ester Enones: Enhanced Reactivity by Inorganic Base. Org Lett 2017; 19:5102-5105. [PMID: 28898087 DOI: 10.1021/acs.orglett.7b02365] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A novel chiral biamide-phosphine multifunctional catalyst has been developed that mediates the asymmetric intermolecular Michael addition of β-carbonyl esters to β-trifluoromethyl enones and 3-aroyl acrylates in the presence of competing methyl acrylate and the inorganic base. This method provides a facile access to structurally diverse trifluoromethyl and quaternary stereogenic centers with excellent enantioselectivity (up to 99% ee) and good diastereoselectivity (up to 13:1 dr). The addition of the inorganic base (K3PO4) does not cause the background racemic reaction and enhances the reactivity by serving as a co-catalyst.
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Affiliation(s)
- Ben Huang
- School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China
| | - Cao Li
- School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China
| | - Huamin Wang
- School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China
| | - Caihui Wang
- School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China
| | - Lu Liu
- School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China
| | - Junliang Zhang
- School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China
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562
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Shockley SE, Hethcox JC, Stoltz BM. Enantioselective Synthesis of Acyclic α-Quaternary Carboxylic Acid Derivatives through Iridium-Catalyzed Allylic Alkylation. Angew Chem Int Ed Engl 2017; 56:11545-11548. [PMID: 28722280 DOI: 10.1002/anie.201707015] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Indexed: 01/01/2023]
Abstract
The first highly enantioselective iridium-catalyzed allylic alkylation that provides 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 α-quaternary carboxylic acids, esters, and amides with a high degree of enantioselectivity. The utility of these products is further explored through a series of diverse product transformations.
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Affiliation(s)
- 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
| | - 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
| | - 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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563
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Xu S, Wang C, Komiyama M, Tomonari Y, Negishi EI. Asymmetric Synthesis of Chiral Cyclopentanes Bearing an All-Carbon Quaternary Stereocenter by Zirconium-Catalyzed Double Carboalumination. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201706198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shiqing Xu
- Herbert C. Brown Laboratories of Chemistry; Purdue University; 560 Oval Drive West Lafayette IN 47906 USA
| | - Chuan Wang
- Herbert C. Brown Laboratories of Chemistry; Purdue University; 560 Oval Drive West Lafayette IN 47906 USA
- Department of Chemistry; University of Science and Technology of China; 96 Jinzhai Road, Heifei Anhui 230026 P.R. China
| | - Masato Komiyama
- Herbert C. Brown Laboratories of Chemistry; Purdue University; 560 Oval Drive West Lafayette IN 47906 USA
| | - Yasuhiko Tomonari
- Herbert C. Brown Laboratories of Chemistry; Purdue University; 560 Oval Drive West Lafayette IN 47906 USA
| | - Ei-ichi Negishi
- Herbert C. Brown Laboratories of Chemistry; Purdue University; 560 Oval Drive West Lafayette IN 47906 USA
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564
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Xu S, Wang C, Komiyama M, Tomonari Y, Negishi EI. Asymmetric Synthesis of Chiral Cyclopentanes Bearing an All-Carbon Quaternary Stereocenter by Zirconium-Catalyzed Double Carboalumination. Angew Chem Int Ed Engl 2017; 56:11502-11505. [PMID: 28726306 DOI: 10.1002/anie.201706198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 07/12/2017] [Indexed: 11/10/2022]
Abstract
Herein, we report a zirconium-catalyzed enantio- and diastereoselective inter/intramolecular double carboalumination of unactivated 2-substituted 1,5-dienes, which provides efficient and direct access to chiral cyclopentanes through the generation of two stereocenters, including one all-carbon quaternary stereocenter, generally with excellent diastereo- and high enantioselectivity. This tandem carboalumination process creates two new C-C bonds as well as one C-Al bond, which can be oxidized in situ with O2 or hydrolyzed. Furthermore, the obtained chiral cyclopentanes can be readily functionalized to provide various chiral compounds.
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Affiliation(s)
- Shiqing Xu
- Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47906, USA
| | - Chuan Wang
- Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47906, USA.,Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Heifei, Anhui, 230026, P.R. China
| | - Masato Komiyama
- Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47906, USA
| | - Yasuhiko Tomonari
- Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47906, USA
| | - Ei-Ichi Negishi
- Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47906, USA
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565
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Pace V, Castoldi L, Mazzeo E, Rui M, Langer T, Holzer W. Efficient Access to All‐Carbon Quaternary and Tertiary α‐Functionalized Homoallyl‐type Aldehydes from Ketones. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201706236] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Vittorio Pace
- Department of Pharmaceutical Chemistry University of Vienna Althanstrasse, 14 1090 Vienna Austria
| | - Laura Castoldi
- Department of Pharmaceutical Chemistry University of Vienna Althanstrasse, 14 1090 Vienna Austria
| | - Eugenia Mazzeo
- Department of Pharmaceutical Chemistry University of Vienna Althanstrasse, 14 1090 Vienna Austria
| | - Marta Rui
- Department of Pharmaceutical Chemistry University of Vienna Althanstrasse, 14 1090 Vienna Austria
| | - Thierry Langer
- Department of Pharmaceutical Chemistry University of Vienna Althanstrasse, 14 1090 Vienna Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry University of Vienna Althanstrasse, 14 1090 Vienna Austria
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566
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Pace V, Castoldi L, Mazzeo E, Rui M, Langer T, Holzer W. Efficient Access to All-Carbon Quaternary and Tertiary α-Functionalized Homoallyl-type Aldehydes from Ketones. Angew Chem Int Ed Engl 2017; 56:12677-12682. [PMID: 28722252 DOI: 10.1002/anie.201706236] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Indexed: 12/30/2022]
Abstract
β,γ-Unsaturated aldehydes with all-carbon quaternary or tertiary α-centers were rapidly assembled from ketones through a unique synthetic operation consisting of 1) C1 homologation, 2) Lewis acid mediated epoxide-aldehyde isomerization, and 3) electrophilic trapping. The synthetic equivalence of a vinyl oxirane and a β,γ-unsaturated aldehyde is the key concept of this previously undisclosed tactic. Mechanistic studies and labeling experiments suggest that an aldehyde enolate is a crucial intermediate. The homologating carbenoid formation plays a critical role in determining the chemoselectivity.
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Affiliation(s)
- Vittorio Pace
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090, Vienna, Austria
| | - Laura Castoldi
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090, Vienna, Austria
| | - Eugenia Mazzeo
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090, Vienna, Austria
| | - Marta Rui
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090, Vienna, Austria
| | - Thierry Langer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090, Vienna, Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse, 14, 1090, Vienna, Austria
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567
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Choudhury AR, Manna MS, Mukherjee S. Nitro-enabled catalytic enantioselective formal umpolung alkenylation of β-ketoesters. Chem Sci 2017; 8:6686-6690. [PMID: 28989696 PMCID: PMC5625255 DOI: 10.1039/c7sc02232h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/30/2017] [Indexed: 01/10/2023] Open
Abstract
A formal umpolung strategy is presented for the enantioselective installation of an alkenyl group with a terminal double bond at a tertiary center. This one-pot two-step sequence relies on the unique features of the nitro group, which after inverting the polarity of the alkenylating agent toward the desired bond formation, itself serves as a leaving group. The application of this protocol to cyclic β-ketoesters results in densely functionalized products, bearing an all-carbon quaternary stereocenter including an alkenyl substituent with a terminal double bond, in high yields with excellent enantioselectivities.
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Affiliation(s)
- Abhijnan Ray Choudhury
- Department of Organic Chemistry , Indian Institute of Science , Bangalore 560 012 , India . ; ; Tel: +91-80-2293-2850
| | - Madhu Sudan Manna
- Department of Organic Chemistry , Indian Institute of Science , Bangalore 560 012 , India . ; ; Tel: +91-80-2293-2850
| | - Santanu Mukherjee
- Department of Organic Chemistry , Indian Institute of Science , Bangalore 560 012 , India . ; ; Tel: +91-80-2293-2850
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568
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Dai J, Xiong D, Yuan T, Liu J, Chen T, Shao Z. Chiral Primary Amine Catalysis for Asymmetric Mannich Reactions of Aldehydes with Ketimines: Stereoselectivity and Reactivity. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201706304] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jun Dai
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology Yunnan University Kunming 650091 China
| | - Dan Xiong
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology Yunnan University Kunming 650091 China
| | - Tengrui Yuan
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology Yunnan University Kunming 650091 China
| | - Juan Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology Yunnan University Kunming 650091 China
| | - Tao Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology Yunnan University Kunming 650091 China
| | - Zhihui Shao
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology Yunnan University Kunming 650091 China
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569
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Dai J, Xiong D, Yuan T, Liu J, Chen T, Shao Z. Chiral Primary Amine Catalysis for Asymmetric Mannich Reactions of Aldehydes with Ketimines: Stereoselectivity and Reactivity. Angew Chem Int Ed Engl 2017; 56:12697-12701. [PMID: 28786162 DOI: 10.1002/anie.201706304] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 07/17/2017] [Indexed: 01/01/2023]
Abstract
The application potential of primary amine catalysts in the context of Mannich reactions of aldehydes with ketimines is exemplified by isatin-derived ketimines and cyclic trifluoromethyl ketimines. Primary amine catalysts exhibit either unusual stereoselectivity or reactivity, which is not observable with secondary amine catalysts. Moreover, reversal of diastereofacial selectivity between primary and secondary amine catalysts is disclosed. These new reactions provide useful methods for the syntheses of chiral 3-substituted 3-amino-2-oxindoles and dihydroquinazolinones bearing a trifluoromethylated quaternary stereocenter. The synthetic utility of the reactions is demonstrated through the formal synthesis of AG-041R and DPC 083 and the total synthesis of (-)-psychotriasine.
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Affiliation(s)
- Jun Dai
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China
| | - Dan Xiong
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China
| | - Tengrui Yuan
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China
| | - Juan Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China
| | - Tao Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China
| | - Zhihui Shao
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China
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570
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Qin X, Lee MWY, Zhou JS. Nickel‐Catalyzed Asymmetric Reductive Heck Cyclization of Aryl Halides to Afford Indolines. Angew Chem Int Ed Engl 2017; 56:12723-12726. [DOI: 10.1002/anie.201707134] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 08/11/2017] [Indexed: 12/12/2022]
Affiliation(s)
- Xurong Qin
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
| | - Marcus Wen Yao Lee
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
| | - Jianrong Steve Zhou
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
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571
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Qin X, Lee MWY, Zhou JS. Nickel‐Catalyzed Asymmetric Reductive Heck Cyclization of Aryl Halides to Afford Indolines. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707134] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xurong Qin
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
| | - Marcus Wen Yao Lee
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
| | - Jianrong Steve Zhou
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
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572
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Shockley SE, Hethcox JC, Stoltz BM. Asymmetric Synthesis of All-Carbon Quaternary Spirocycles via a Catalytic Enantioselective Allylic Alkylation Strategy. Tetrahedron Lett 2017; 58:3341-3343. [PMID: 28867835 PMCID: PMC5578629 DOI: 10.1016/j.tetlet.2017.07.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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.
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Affiliation(s)
| | | | - 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 East California Blvd, MC 101-20, Pasadena, California 91125, United States
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573
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Reddy ACS, Choutipalli VSK, Ghorai J, Subramanian V, Anbarasan P. Stereoselective Palladium-Catalyzed Synthesis of Indolines via Intramolecular Trapping of N-Ylides with Alkenes. ACS Catal 2017. [DOI: 10.1021/acscatal.7b02072] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Jayanta Ghorai
- Department
of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | | | - Pazhamalai Anbarasan
- Department
of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
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574
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Shockley SE, Hethcox JC, Stoltz BM. Enantioselective Synthesis of Acyclic α-Quaternary Carboxylic Acid Derivatives through Iridium-Catalyzed Allylic Alkylation. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- 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
| | - 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
| | - 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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575
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Kim DK, Riedel J, Kim RS, Dong VM. Cobalt Catalysis for Enantioselective Cyclobutanone Construction. J Am Chem Soc 2017; 139:10208-10211. [PMID: 28704053 PMCID: PMC6824591 DOI: 10.1021/jacs.7b05327] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Over the past 40 years, intramolecular hydroacylation has favored five-membered rings, in preference to four membered rings. Herein, we report a catalyst derived from earth-abundant cobalt that enables preparation of cyclobutanones, with excellent regio-, diastereo-, and enantiocontrol, under mild conditions (2 mol % catalyst loading and as low as 50 °C).
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Affiliation(s)
- Daniel K. Kim
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Jan Riedel
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Raphael S. Kim
- 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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576
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Donahue MG, Jentsch NG, Realini EC. An intramolecular para-phenolic allylation free radical cyclization strategy for the synthesis of alkaloids and terpenes with spiro[4.5]decane architectures. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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577
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Fu GC. Transition-Metal Catalysis of Nucleophilic Substitution Reactions: A Radical Alternative to S N1 and S N2 Processes. ACS CENTRAL SCIENCE 2017; 3:692-700. [PMID: 28776010 PMCID: PMC5532721 DOI: 10.1021/acscentsci.7b00212] [Citation(s) in RCA: 385] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Indexed: 05/21/2023]
Abstract
Classical methods for achieving nucleophilic substitutions of alkyl electrophiles (SN1 and SN2) have limited scope and are not generally amenable to enantioselective variants that employ readily available racemic electrophiles. Radical-based pathways catalyzed by chiral transition-metal complexes provide an attractive approach to addressing these limitations.
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578
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Primer DN, Molander GA. Enabling the Cross-Coupling of Tertiary Organoboron Nucleophiles through Radical-Mediated Alkyl Transfer. J Am Chem Soc 2017; 139:9847-9850. [PMID: 28719197 PMCID: PMC5605792 DOI: 10.1021/jacs.7b06288] [Citation(s) in RCA: 182] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The construction of quaternary centers is a common challenge in the synthesis of complex materials and natural products. Current cross-coupling strategies that can be generalized for setting these centers are sparse and, when known, are typically predicated on the use of reactive organometallic reagents. To address this shortcoming a new, photoredox-Ni dual catalytic strategy for the cross-coupling of tertiary organoboron reagents with aryl halides is reported. In addition to details on the cross-coupling scope and limitations, full screening efforts and mechanistic experiments are communicated.
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Affiliation(s)
- David N. Primer
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Gary A. Molander
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
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579
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Huo X, He R, Fu J, Zhang J, Yang G, Zhang W. Stereoselective and Site-Specific Allylic Alkylation of Amino Acids and Small Peptides via a Pd/Cu Dual Catalysis. J Am Chem Soc 2017; 139:9819-9822. [DOI: 10.1021/jacs.7b05460] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Xiaohong Huo
- School
of Chemistry and Chemical Engineering and ‡School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
| | - Rui He
- School
of Chemistry and Chemical Engineering and ‡School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
| | - Jingke Fu
- School
of Chemistry and Chemical Engineering and ‡School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
| | - Jiacheng Zhang
- School
of Chemistry and Chemical Engineering and ‡School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
| | - Guoqiang Yang
- School
of Chemistry and Chemical Engineering and ‡School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
| | - Wanbin Zhang
- School
of Chemistry and Chemical Engineering and ‡School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China
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580
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Ma H, Xie L, Zhang Z, Wu LG, Fu B, Qin Z. Enantioselective Conjugate Addition of 2-Acetyl Azaarenes to β,β-Disubstituted Nitroalkene for the Construction of All-Carbon Quaternary Stereocenters. J Org Chem 2017; 82:7353-7362. [DOI: 10.1021/acs.joc.7b01014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Hongli Ma
- Department of Applied
Chemistry, China Agricultural University, Beijing 100193, P. R. China
| | - Lei Xie
- Department of Applied
Chemistry, China Agricultural University, Beijing 100193, P. R. China
| | - Zhenhua Zhang
- Department of Applied
Chemistry, China Agricultural University, Beijing 100193, P. R. China
| | - Lin-gang Wu
- Department of Applied
Chemistry, China Agricultural University, Beijing 100193, P. R. China
| | - Bin Fu
- Department of Applied
Chemistry, China Agricultural University, Beijing 100193, P. R. China
| | - Zhaohai Qin
- Department of Applied
Chemistry, China Agricultural University, Beijing 100193, P. R. China
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581
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Starkov P, Moore JT, Duquette DC, Stoltz BM, Marek I. Enantioselective Construction of Acyclic Quaternary Carbon Stereocenters: Palladium-Catalyzed Decarboxylative Allylic Alkylation of Fully Substituted Amide Enolates. J Am Chem Soc 2017. [PMID: 28625056 DOI: 10.1021/jacs.7b04086] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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.
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Affiliation(s)
- Pavel Starkov
- 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 , Technion City, Haifa 32000, Israel
| | - Jared T Moore
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - Douglas C Duquette
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - Brian M Stoltz
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - 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 , Technion City, Haifa 32000, Israel
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582
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Affiliation(s)
- Shu-An Liu
- Department
of Chemistry and Center for Integrated Protein Science, Ludwig-Maximilian University Munich, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Dirk Trauner
- Department
of Chemistry and Center for Integrated Protein Science, Ludwig-Maximilian University Munich, Butenandtstraße 5-13, 81377 Munich, Germany
- Department
of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
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583
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Du K, Yang H, Guo P, Feng L, Xu G, Zhou Q, Chung LW, Tang W. Efficient syntheses of (-)-crinine and (-)-aspidospermidine, and the formal synthesis of (-)-minfiensine by enantioselective intramolecular dearomative cyclization. Chem Sci 2017; 8:6247-6256. [PMID: 28989658 PMCID: PMC5628388 DOI: 10.1039/c7sc01859b] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/30/2017] [Indexed: 11/21/2022] Open
Abstract
Palladium-catalyzed enantioselective dearomative cyclization has enabled the concise and enantioselective total syntheses of (–)-crinine and (–)-aspidospermidine, as well as a formal total synthesis of (–)-minfiensine.
Polycyclic alkaloids bearing all-carbon quaternary centers possess a diversity of biological activities and are challenging targets in natural product synthesis. The development of a general and asymmetric catalytic method applicable to the efficient syntheses of a series of complex polycyclic alkaloids remains highly desirable in synthetic chemistry. Herein we describe an efficient palladium-catalyzed enantioselective dearomative cyclization which is capable of synthesizing two important classes of tricyclic nitrogen-containing skeleton, chiral dihydrophenanthridinone and dihydrocarbazolone derivatives bearing all-carbon quaternary centers, in excellent yields and enantioselectivities. The P-chiral monophosphorus ligand AntPhos is crucial for the reactivity and enantioselectivity, and the choice of the N-phosphoramide protecting group is essential for the desired chemoselectivity. This method has enabled the enantioselective total syntheses of three distinctive and challenging biologically important polycyclic alkaloids, specifically a concise and gram-scale synthesis of (–)-crinine, an efficient synthesis of indole alkaloid (–)-aspidospermidine and a formal enantioselective synthesis of (–)-minfiensine.
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Affiliation(s)
- Kang Du
- State Key Laboratory of Bio-Organic & Natural Products Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - He Yang
- State Key Laboratory of Bio-Organic & Natural Products Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - Pan Guo
- State Key Laboratory of Bio-Organic & Natural Products Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - Liang Feng
- State Key Laboratory of Bio-Organic & Natural Products Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - Guangqing Xu
- State Key Laboratory of Bio-Organic & Natural Products Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - Qinghai Zhou
- Department of Chemistry , South University of Science and Technology of China , Shenzhen 518055 , China.,College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Lung Wa Chung
- Department of Chemistry , South University of Science and Technology of China , Shenzhen 518055 , China
| | - Wenjun Tang
- State Key Laboratory of Bio-Organic & Natural Products Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
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584
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Li H, Lu Y. Enantioselective Construction of All-Carbon Quaternary Stereogenic Centers by Using Phosphine Catalysis. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700220] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Huilin Li
- Department of Chemistry; National University of Singapore; 3 Science Drive 3 117543 Singapore Singapore
| | - Yixin Lu
- Department of Chemistry; National University of Singapore; 3 Science Drive 3 117543 Singapore Singapore
- National University of Singapore (Suzhou); Research Institute; 377 Lin Quan Street, Suzhou Industrial Park Suzhou Jiangsu 215123 P. R. China
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585
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Dange NS, Hussain Jatoi A, Robert F, Landais Y. Visible-Light-Mediated Addition of Phenacyl Bromides onto Cyclopropenes. Org Lett 2017; 19:3652-3655. [PMID: 28656767 DOI: 10.1021/acs.orglett.7b01651] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [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
| | - Ashique Hussain Jatoi
- 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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586
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Schempp TT, Daniels BE, Staben ST, Stivala CE. A General Strategy for the Construction of Functionalized Azaindolines via Domino Palladium-Catalyzed Heck Cyclization/Suzuki Coupling. Org Lett 2017; 19:3616-3619. [DOI: 10.1021/acs.orglett.7b01606] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tabitha T. Schempp
- Discovery Chemistry Group, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Blake E. Daniels
- Discovery Chemistry Group, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Steven T. Staben
- Discovery Chemistry Group, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Craig E. Stivala
- Discovery Chemistry Group, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, United States
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587
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Huang X, Quinn TR, Harms K, Webster RD, Zhang L, Wiest O, Meggers E. Direct Visible-Light-Excited Asymmetric Lewis Acid Catalysis of Intermolecular [2+2] Photocycloadditions. J Am Chem Soc 2017. [DOI: 10.1021/jacs.7b04363] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Xiaoqiang Huang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Taylor R. Quinn
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Klaus Harms
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Richard D. Webster
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Lilu Zhang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Olaf Wiest
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Laboratory of Computational Chemistry and Drug Design, School of Chemical Biology and Biotechnology, Peking University, Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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588
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Holmes M, Nguyen KD, Schwartz LA, Luong T, Krische MJ. Enantioselective Formation of CF 3-Bearing All-Carbon Quaternary Stereocenters via C-H Functionalization of Methanol: Iridium Catalyzed Allene Hydrohydroxymethylation. J Am Chem Soc 2017; 139:8114-8117. [PMID: 28603973 PMCID: PMC5651675 DOI: 10.1021/jacs.7b04374] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Using an iridium catalyst modified by PhanePhos, CF3-allenes react with methanol to form branched products of hydrohydroxymethylation as single regioisomers with excellent levels of enantiomeric enrichment. This hydrogen autotransfer process enables catalytic enantioselective formation of acyclic CF3-bearing all-carbon quaternary stereocenters in the absence of stoichiometric metals or byproducts.
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Affiliation(s)
- Michael Holmes
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Khoa D. Nguyen
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Leyah A. Schwartz
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Tom Luong
- 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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589
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Medina JM, Moreno J, Racine S, Du S, Garg NK. Mizoroki-Heck Cyclizations of Amide Derivatives for the Introduction of Quaternary Centers. Angew Chem Int Ed Engl 2017; 56:6567-6571. [PMID: 28467029 PMCID: PMC5669036 DOI: 10.1002/anie.201703174] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Indexed: 12/26/2022]
Abstract
We report non-decarbonylative Mizoroki-Heck reactions of amide derivatives. The transformation relies on the use of nickel catalysis and proceeds using sterically hindered tri- and tetrasubstituted olefins to give products containing quaternary centers. The resulting polycyclic or spirocyclic products can be obtained in good yields. Moreover, a diastereoselective variant of this method gives access to an adduct bearing vicinal, highly substituted sp3 stereocenters. These results demonstrate that amide derivatives can be used as building blocks for the assembly of complex scaffolds.
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Affiliation(s)
- Jose M Medina
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Jesus Moreno
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Sophie Racine
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Shuaijing Du
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Neil K Garg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, 90095, USA
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590
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Medina JM, Moreno J, Racine S, Du S, Garg NK. Mizoroki–Heck Cyclizations of Amide Derivatives for the Introduction of Quaternary Centers. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201703174] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Jose M. Medina
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095 USA
| | - Jesus Moreno
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095 USA
| | - Sophie Racine
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095 USA
| | - Shuaijing Du
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095 USA
| | - Neil K. Garg
- Department of Chemistry and Biochemistry University of California, Los Angeles Los Angeles CA 90095 USA
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591
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Wang F, Meng Q. Mechanism for ruthenium hydride-catalyzed regioselective hydroacylation of enones and aldehydes to give 1,3-diketones: Insights from density functional calculations. MOLECULAR CATALYSIS 2017. [DOI: 10.1016/j.mcat.2017.02.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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592
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Jin Q, Zheng C, Zhao G, Zou G. Bifunctional Quaternary Ammonium Salts Catalyzed Stereoselective Conjugate Addition of Oxindoles to Electron-Deficient β-Haloalkenes. J Org Chem 2017; 82:4840-4850. [DOI: 10.1021/acs.joc.7b00571] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Qiaowen Jin
- School of Chemistry & Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
| | - Changwu Zheng
- Key
Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Gang Zhao
- Key
Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Gang Zou
- School of Chemistry & Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
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593
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Jenkins EN, Czaplyski WL, Alexanian EJ. A General Approach to Quaternary Center Construction from Couplings of Unactivated Alkenes and Acyl Xanthates. Org Lett 2017; 19:2350-2353. [DOI: 10.1021/acs.orglett.7b00882] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Ernest N. Jenkins
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - William L. Czaplyski
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Erik J. Alexanian
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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594
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Affiliation(s)
- Ganapathy Sivakumar
- Department of Engineering Technology, College of Technology, University of Houston, Houston, TX, USA
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595
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Hajra S, Roy S, Maity S. Reversal of Selectivity in C3-Allylation and Formal [3 + 2]-Cycloaddition of Spiro-epoxyoxindole: Unified Synthesis of Spiro-furanooxindole, (±)-N-Methylcoerulescine, (±)-Physovenine, and 3a-Allylhexahydropyrrolo[2,3-b]indole. Org Lett 2017; 19:1998-2001. [DOI: 10.1021/acs.orglett.7b00420] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Saumen Hajra
- Centre
of Biomedical Research, Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, India
| | - Sayan Roy
- Centre
of Biomedical Research, Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, India
| | - Subrata Maity
- Centre
of Biomedical Research, Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, India
- Department
of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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596
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Li XQ, Yang H, Wang JJ, Gou BB, Chen J, Zhou L. Asymmetric Arylative Dearomatization of β-Naphthols Catalyzed by a Chiral Phosphoric Acid. Chemistry 2017; 23:5381-5385. [DOI: 10.1002/chem.201701015] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Xiao-Qiang Li
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Department of Chemistry & 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 & Materials Science; Northwest University; Xi'an 710127 P. R. China
| | - Jiao-Jiao Wang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Department of Chemistry & Materials Science; Northwest University; Xi'an 710127 P. R. China
| | - Bo-Bo Gou
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Department of Chemistry & 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 & 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 & Materials Science; Northwest University; Xi'an 710127 P. R. China
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597
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Tan Q, Wang X, Xiong Y, Zhao Z, Li L, Tang P, Zhang M. Chiral Amino Alcohol Accelerated and Stereocontrolled Allylboration of Iminoisatins: Highly Efficient Construction of Adjacent Quaternary Stereogenic Centers. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700581] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Qiuyuan Tan
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Xinqiao Wang
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Yang Xiong
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Zimeng Zhao
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Lu Li
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Pei Tang
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Min Zhang
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
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598
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Tan Q, Wang X, Xiong Y, Zhao Z, Li L, Tang P, Zhang M. Chiral Amino Alcohol Accelerated and Stereocontrolled Allylboration of Iminoisatins: Highly Efficient Construction of Adjacent Quaternary Stereogenic Centers. Angew Chem Int Ed Engl 2017; 56:4829-4833. [DOI: 10.1002/anie.201700581] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Indexed: 01/26/2023]
Affiliation(s)
- Qiuyuan Tan
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Xinqiao Wang
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Yang Xiong
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Zimeng Zhao
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Lu Li
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Pei Tang
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
| | - Min Zhang
- Innovative Drug Research Centre; School of Pharmaceutical Sciences; Chongqing University; 55 Daxuecheng South Road, Shapingba Chongqing 401331 China
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599
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Wang F, Meng Q. Theoretical Studies for Switching Regioselectivity in Ruthenium Hydride-Catalyzed Alkyne Hydroacylation. ChemistrySelect 2017. [DOI: 10.1002/slct.201601968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Fen Wang
- College of Chemistry and Material Science; Shandong Agricultural University; Daizong Road No. 61. Taian Shandong 271018 China
- College of Chemistry and Chemical Engineering; Taishan University; Dongyue Road No. 525, Taian Shandong 271000 China
| | - Qingxi Meng
- College of Chemistry and Material Science; Shandong Agricultural University; Daizong Road No. 61. Taian Shandong 271018 China
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600
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Bahamonde A, Murphy JJ, Savarese M, Brémond É, Cavalli A, Melchiorre P. Studies on the Enantioselective Iminium Ion Trapping of Radicals Triggered by an Electron-Relay Mechanism. J Am Chem Soc 2017; 139:4559-4567. [PMID: 28281754 PMCID: PMC5374491 DOI: 10.1021/jacs.7b01446] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
![]()
A combination of
electrochemical, spectroscopic, computational,
and kinetic studies has been used to elucidate the key mechanistic
aspects of the previously reported enantioselective iminium ion trapping
of photochemically generated carbon-centered radicals. The process,
which provides a direct way to forge quaternary stereocenters with
high fidelity, relies on the interplay of two distinct catalytic cycles:
the aminocatalytic electron-relay system, which triggers the stereoselective
radical trap upon iminium ion formation, and the photoredox cycle,
which generates radicals under mild conditions. Critical to reaction
development was the use of a chiral amine catalyst, bearing a redox-active
carbazole unit, which could rapidly reduce the highly reactive and
unstable intermediate generated upon radical interception. The carbazole
unit, however, is also involved in another step of the electron-relay
mechanism: the transiently generated carbazole radical cation acts
as an oxidant to return the photocatalyst into the original state.
By means of kinetic and spectroscopic studies, we have identified
the last redox event as being the turnover-limiting step of the overall
process. This mechanistic framework is corroborated by the linear
correlation between the reaction rate and the reduction potential
of the carbazole unit tethered to the aminocatalyst. The redox properties
of the carbazole unit can thus be rationally tuned to improve catalytic
activity. This knowledge may open a path for the mechanistically driven
design of the next generation of electron-relay catalysts.
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Affiliation(s)
- Ana Bahamonde
- ICIQ - Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology , Avinguda Països Catalans 16, 43007 Tarragona, Spain
| | - John J Murphy
- ICIQ - Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology , Avinguda Països Catalans 16, 43007 Tarragona, Spain
| | - Marika Savarese
- D3 CompuNet, Istituto Italiano di Tecnologia , via Morego 30, 16163 Genova, Italy
| | - Éric Brémond
- D3 CompuNet, Istituto Italiano di Tecnologia , via Morego 30, 16163 Genova, Italy
| | - Andrea Cavalli
- D3 CompuNet, Istituto Italiano di Tecnologia , via Morego 30, 16163 Genova, Italy.,Dept. of Pharmacy and Biotechnology, via Belmeloro 6, 40126 Bologna, Italy
| | - Paolo Melchiorre
- ICIQ - Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology , Avinguda Països Catalans 16, 43007 Tarragona, Spain.,ICREA , Passeig Lluís Companys 23, 08010 Barcelona, Spain
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