1
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He YP, Li ZC, Wang ZQ, Zheng WY, Wu H. Enamine Acylation Enabled Desymmetrization of Malonic Esters. J Am Chem Soc 2024. [PMID: 39263905 DOI: 10.1021/jacs.4c09276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2024]
Abstract
Asymmetric enamine alkylation represents a powerful tool for stereoselective C-C bond formation; in contrast, the development of enantioselective enamine acylation remains elusive. Here, we report that a chiral phosphoric acid can render an in-situ-formed enamine to undergo a stereoselective intramolecular α-carbon acylation, providing an alternative approach for the synthesis of useful pyrrolinones and indolinones bearing tetrasubstituted stereocenters. Utilizing an effective integration of the desymmetrization strategy and bifunctional organocatalysis, the first example of enantioselective enamine acylation is achieved by employing readily available aminomalonic esters and cyclic ketones. Instead of reactive and moisture-sensitive acyl chlorides, common esters with low electrophilicity were successfully used as efficient acylating reagents via hydrogen bonding interactions. The utility is demonstrated in the concise and enantioselective synthesis of (+)-LipidGreen I and II. Experimental studies and DFT calculations establish the reaction pathway and the origin of stereocontrol.
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Affiliation(s)
- Yu-Ping He
- Shanghai Frontiers Science Center for Drug Target Identification and Delivery, National Key Laboratory of Innovative Immunotherapy, and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
- Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Zhuo-Chen Li
- Shanghai Frontiers Science Center for Drug Target Identification and Delivery, National Key Laboratory of Innovative Immunotherapy, and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zi-Qi Wang
- Shanghai Frontiers Science Center for Drug Target Identification and Delivery, National Key Laboratory of Innovative Immunotherapy, and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Wen-Ya Zheng
- Shanghai Frontiers Science Center for Drug Target Identification and Delivery, National Key Laboratory of Innovative Immunotherapy, and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hua Wu
- Shanghai Frontiers Science Center for Drug Target Identification and Delivery, National Key Laboratory of Innovative Immunotherapy, and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
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2
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Tian X, Xuan T, Gao J, Zhang X, Liu T, Luo F, Pang R, Shao P, Yang YF, Wang Y. Catalytic enantioselective nitrone cycloadditions enabling collective syntheses of indole alkaloids. Nat Commun 2024; 15:6429. [PMID: 39080291 PMCID: PMC11289135 DOI: 10.1038/s41467-024-50509-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 07/15/2024] [Indexed: 08/02/2024] Open
Abstract
Tetrahydro-β-carboline skeletons are prominent and ubiquitous in an extraordinary range of indole alkaloid natural products and pharmaceutical compounds. Powerful synthetic approaches for stereoselective synthesis of tetrahydro-β-carboline skeletons have immense impacts and have attracted enormous attention. Here, we outline a general chiral phosphoric acid catalyzed asymmetric 1,3-dipolar cycloaddition of 3,4-dihydro-β-carboline-2-oxide type nitrone that enables access to three types of chiral tetrahydro-β-carbolines bearing continuous multi-chiral centers and quaternary chiral centers. The method displays different endo/exo selectivity from traditional nitrone chemistry. The distinct power of this strategy has been illustrated by application to collective and enantiodivergent total syntheses of 40 tetrahydro-β-carboline-type indole alkaloid natural products with divergent stereochemistry and varied architectures.
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Affiliation(s)
- Xiaochen Tian
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
- Laboratory for Marine Drugs and Bioproducts, Qingdao Marine Science and Technology Center, Qingdao, China
| | - Tengfei Xuan
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
- Laboratory for Marine Drugs and Bioproducts, Qingdao Marine Science and Technology Center, Qingdao, China
| | - Jingkun Gao
- State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Chemistry-Synthesis Technology of Zhejiang Province, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Xinyu Zhang
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Tao Liu
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Fengbiao Luo
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Ruochen Pang
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Pengcheng Shao
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Yun-Fang Yang
- State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Chemistry-Synthesis Technology of Zhejiang Province, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China.
| | - Yang Wang
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China.
- Laboratory for Marine Drugs and Bioproducts, Qingdao Marine Science and Technology Center, Qingdao, China.
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3
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Liu B, Zou X, Zhang Y, Yang Y, Xu H, Tang F, Yu H, Xia F, Liu Z, Zhao J, Shi W, Huang W. Site- and Stereoselective Glycomodification of Biomolecules through Carbohydrate-Promoted Pictet-Spengler Reaction. Angew Chem Int Ed Engl 2024; 63:e202401394. [PMID: 38396356 DOI: 10.1002/anie.202401394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/21/2024] [Accepted: 02/22/2024] [Indexed: 02/25/2024]
Abstract
Carbohydrates play pivotal roles in an array of essential biological processes and are consequently involved in many diseases. To meet the needs of glycobiology research, chemical enzymatic and non-enzymatic methods have been developed to generate glycoconjugates with well-defined structures. Herein, harnessing the unique properties of C6-oxidized glycans, we report a straightforward and robust strategy for site- and stereoselective glycomodification of biomolecules with N-terminal tryptophan residues by a carbohydrate-promoted Pictet-Spengler reaction, which is not adapted to typical aldehyde substrates under biocompatible conditions. This method reliably delivers highly homogeneous glycoconjugates with stable linkages and thus has great potential for functional modulation of peptides and proteins in glycobiology research. Moreover, this reaction can be performed at the glycosites of glycopeptides, glycoproteins and living-cell surfaces in a site-specific manner. Control experiments indicated that the protected α-O atom of aldehyde donors and free N-H bond of the tryptamine motif are crucial for this reaction. Mechanistic investigations demonstrated that the reaction exhibited a first-order dependence on both tryptophan and glycan, and deprotonation/rearomatization of the pentahydro-β-carbolinium ion intermediate might be the rate-determining step.
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Affiliation(s)
- Bo Liu
- School of Pharmaceutical Science and Technology, Hangzhou Institute of Advanced Study, Hangzhou, 310024, China
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
| | - Xiangman Zou
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing, 100049, China
- Key Laboratory of Structure-based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Yue Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing, 100049, China
- Key Laboratory of Structure-based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Yang Yang
- School of Pharmaceutical Science and Technology, Hangzhou Institute of Advanced Study, Hangzhou, 310024, China
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
| | - Hao Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, No. 138 Xianlin Rd, Nanjing, 210023, China
| | - Feng Tang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing, 100049, China
| | - Huixin Yu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing, 100049, China
- Key Laboratory of Structure-based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Fei Xia
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing, 100049, China
| | - Zhi Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
| | - Jianwei Zhao
- Shenzhen HUASUAN Technology Co., Ltd, Shenzhen, 518055, China
| | - Wei Shi
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
| | - Wei Huang
- School of Pharmaceutical Science and Technology, Hangzhou Institute of Advanced Study, Hangzhou, 310024, China
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, No.555 Zuchongzhi Rd, Pudong, Shanghai, 201203, China
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing, 100049, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, No. 138 Xianlin Rd, Nanjing, 210023, China
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4
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Gallarati S, van Gerwen P, Laplaza R, Brey L, Makaveev A, Corminboeuf C. A genetic optimization strategy with generality in asymmetric organocatalysis as a primary target. Chem Sci 2024; 15:3640-3660. [PMID: 38455002 PMCID: PMC10915838 DOI: 10.1039/d3sc06208b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 01/30/2024] [Indexed: 03/09/2024] Open
Abstract
A catalyst possessing a broad substrate scope, in terms of both turnover and enantioselectivity, is sometimes called "general". Despite their great utility in asymmetric synthesis, truly general catalysts are difficult or expensive to discover via traditional high-throughput screening and are, therefore, rare. Existing computational tools accelerate the evaluation of reaction conditions from a pre-defined set of experiments to identify the most general ones, but cannot generate entirely new catalysts with enhanced substrate breadth. For these reasons, we report an inverse design strategy based on the open-source genetic algorithm NaviCatGA and on the OSCAR database of organocatalysts to simultaneously probe the catalyst and substrate scope and optimize generality as a primary target. We apply this strategy to the Pictet-Spengler condensation, for which we curate a database of 820 reactions, used to train statistical models of selectivity and activity. Starting from OSCAR, we define a combinatorial space of millions of catalyst possibilities, and perform evolutionary experiments on a diverse substrate scope that is representative of the whole chemical space of tetrahydro-β-carboline products. While privileged catalysts emerge, we show how genetic optimization can address the broader question of generality in asymmetric synthesis, extracting structure-performance relationships from the challenging areas of chemical space.
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Affiliation(s)
- Simone Gallarati
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Puck van Gerwen
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Competence in Research - Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Ruben Laplaza
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Competence in Research - Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Lucien Brey
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Alexander Makaveev
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Clemence Corminboeuf
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Competence in Research - Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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5
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Murata R, Shitamichi K, Hiramatsu M, Matsubara S, Uraguchi D, Asano K. trans-Cyclooctenes as Scavengers of Bromine Involved in Catalytic Bromination. Chemistry 2024; 30:e202303399. [PMID: 38117956 DOI: 10.1002/chem.202303399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Indexed: 12/22/2023]
Abstract
Scavengers that capture reactive chemical substances are used to prevent the decomposition of materials. However, in the field of catalysis, the development of scavengers that inhibit background pathways has attracted little attention, although the concept will open up an otherwise inaccessible reaction space. In catalytic bromination, fast non-catalyzed background reactions disturb the catalytic control of the selectivity, even when using N-bromoamide reagents, which have a milder reactivity than bromine (Br2 ). Here, we developed a trans-cyclooctene (TCO) bearing a 2-pyridylethyl group to efficiently retard background reactions by capturing Br2 in bromocyclization using N-bromosuccinimide. The use of less than a stoichiometric amount of the TCO was sufficient to inhibit non-catalyzed reactions, and mechanistic studies using the TCO revealed that in situ-generated Br2 provides non-catalyzed reaction pathways based on a chain mechanism. The TCO is useful as an additive for improving enantioselectivity and regioselectivity in catalytic reactions. Cooperative systems using the TCO with selective catalysts offer an alternative strategy for optimizing catalyst-controlled selectivity during bromination. Moreover, it also served as an indicator of Br2 involved in catalytic reaction pathways; thus, the TCO was useful as a probe for mechanistic investigations into the involvement of Br2 in bromination reactions of interest.
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Affiliation(s)
- Ryuichi Murata
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo, Kyoto, 615-8510, Japan
| | - Kenta Shitamichi
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo, Kyoto, 615-8510, Japan
| | - Masatsugu Hiramatsu
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo, Kyoto, 615-8510, Japan
| | - Seijiro Matsubara
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo, Kyoto, 615-8510, Japan
| | - Daisuke Uraguchi
- Institute for Catalysis, Hokkaido University, Sapporo, Hokkaido, 001-0021, Japan
- List Sustainable Digital Transformation Catalyst Collaboration Research Platform, Institute for Chemical Reaction Design and Discovery (ICReDD List-PF), Hokkaido University, Sapporo, Hokkaido, 001-0021, Japan
| | - Keisuke Asano
- Institute for Catalysis, Hokkaido University, Sapporo, Hokkaido, 001-0021, Japan
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6
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Sorensen CC, Bhat V, Bello AY, Leibfarth FA. Mechanistic Insights into the Stereoselective Cationic Polymerization of N-Vinylcarbazole. ACS Catal 2023; 13:12163-12172. [PMID: 38469177 PMCID: PMC10927002 DOI: 10.1021/acscatal.3c02165] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
The synthesis of stereoregular polymers through ionic mechanisms using asymmetric ion-pairing (AIP) catalysis is emerging as an effective strategy to achieve differentiated material properties from readily available building blocks. Stereoselective cationic polymerization in particular is primed for advancement using AIP by leveraging the breadth of Brønsted and Lewis acid small-molecule catalysis literature; however, mechanistic studies that address polymer-specific phenomena are scarce and, as a result, the lack of mechanistic understanding has limited catalyst design. In a recent study, we demonstrated the only example of a stereoselective and helix-sense-selective cationic vinyl polymerization of N-vinylcarbazole using chiral scandium-bis(oxazoline) Lewis acids. To better understand the mechanism of this highly stereoselective polymerization and elicit design principles for future advances, we present a combined experimental and computational study into the relevant factors that determine tacticity and helicity control. Key mechanistic experiments suggest two competing elementary steps-chain-end conformation equilibration and propagation-whose relative rates can be influenced by monomer concentration, isotope effects, and catalyst design to tune tacticity. In contrast, helicity is influenced by complex relationships between the stereoselectivity of the first monomer propagation and a time-dependent initiator-catalyst mixing time. The more complete understanding of stereoselective cationic polymerization through AIP developed herein provides insights into polymer-specific mechanisms for stereocontrol, which we believe will motivate continued catalyst discovery and development for stereoselective vinyl polymerization.
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Affiliation(s)
- Cole C Sorensen
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Vittal Bhat
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Anthony Y Bello
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Frank A Leibfarth
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, United States
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7
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Biswas A. Organocatalyzed Asymmetric Pictet‐Spengler Reactions. ChemistrySelect 2023. [DOI: 10.1002/slct.202203368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Anup Biswas
- Departmentof Chemistry Hooghly Women's College Vivekanada Road, Pipulpati Hooghly 712102 India
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8
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Andres R, Sun F, Wang Q, Zhu J. Organocatalytic Enantioselective Pictet-Spengler Reaction of α-Ketoesters: Development and Application to the Total Synthesis of (+)-Alstratine A. Angew Chem Int Ed Engl 2023; 62:e202213831. [PMID: 36347809 DOI: 10.1002/anie.202213831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Indexed: 11/10/2022]
Abstract
We report herein an asymmetric Pictet-Spengler reaction of α-ketoesters. In the presence of a catalytic amount of simple alanine-derived squaramide and p-nitrobenzoic acid, reaction of tryptamines with methyl 2-oxoalkanoates afforded the corresponding 1-alkyl-1-methoxycarbonyl tetrahydro-β-carbolines (THBCs) in high yields and ee values. A primary kinetic isotope effect (KIE=4.5) using C2-deteurium-labelled tryptamine indicates that rearomatization through deprotonation of the pentahydro-β-carbolinium ion could be the rate- and enantioselectivity-determining step. A concise enantioselective total synthesis of (+)-alstratine A, a hexacyclic cagelike monoterpene indole alkaloid, featuring this reaction as a key step, was subsequently accomplished. Remeasurement of the [a]D value of the natural product indicates that natural alstratine A is dextrorotatory rather than levorotatory as it was initially reported in the isolation paper.
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Affiliation(s)
- Rémi Andres
- Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH, 5304, 1015, Lausanne, Switzerland
| | - Fenggang Sun
- Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH, 5304, 1015, Lausanne, Switzerland.,School of Chemical Engineering, Shandong University of Technology, Zibo, 255049, P. R. China
| | - Qian Wang
- Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH, 5304, 1015, Lausanne, Switzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH, 5304, 1015, Lausanne, Switzerland
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9
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Samha MH, Wahlman JLH, Read JA, Werth J, Jacobsen EN, Sigman MS. Exploring Structure-Function Relationships of Aryl Pyrrolidine-Based Hydrogen-Bond Donors in Asymmetric Catalysis Using Data-Driven Techniques. ACS Catal 2022; 12:14836-14845. [PMID: 36816226 PMCID: PMC9937582 DOI: 10.1021/acscatal.2c04824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hydrogen bond-based organocatalysts rely on networks of attractive noncovalent interactions (NCIs) to impart enantioselectivity. As a specific example, aryl pyrrolidine substituted urea, thiourea, and squaramide organocatalysts function cooperatively through hydrogen bonding and difficult-to-predict NCIs as a function of the reaction partners. To uncover the synergistic effect of the structural components of this catalyst class, we applied data science tools to study various model reactions using a derivatized, aryl pyrrolidine-based, hydrogen-bond donor (HBD) catalyst library. Through a combination of experimentally collected data and data mined from previous reports, statistical models were constructed, illuminating the general features necessary for high enantioselectivity. A distinct dependence on the identity of the electrophilic reaction partner and HBD catalyst is observed, suggesting that a general interaction is conserved throughout the reactions analyzed. The resulting models also demonstrate predictive capability by the successful improvement of a previously reported reaction using out-of-sample reaction components. Overall, this study highlights the power of data science in exploring mechanistic hypotheses in asymmetric HBD catalysis and provides a prediction platform applicable in future reaction optimization.
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Affiliation(s)
- Mohammad H. Samha
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Julie L. H. Wahlman
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Jacquelyne A. Read
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States; Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Jacob Werth
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Eric N. Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Matthew S. Sigman
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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10
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Wiley RE, McLaughlin MF, Johnson JS. Dearomatization of Cyclic Diphenylhydrazines: Harnessing the o-Semidine Rearrangement for the Synthesis of Spirocyclic Tetrahydroquinolines. Org Lett 2022; 24:8014-8018. [PMID: 36269213 PMCID: PMC9678246 DOI: 10.1021/acs.orglett.2c03220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis of novel tetrahydroquinoline-containing spirocycles has been achieved through an acid-promoted dearomatization of cyclic diarylhydrazines. The reaction, proceeding through a dearomative o-semidine rearrangement, furnishes a stable, yet reactive spirocyclohexadieniminium ion, which can further be used as an electrophile or a diene in a one-pot sequence. These transformations efficiently produce novel diazaspirocycles and allow for further synthetic elaboration of the cyclohexadienamine products.
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Affiliation(s)
- Robert E Wiley
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 25799-3290, United States
| | - Michael F McLaughlin
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 25799-3290, United States
| | - Jeffrey S Johnson
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 25799-3290, United States
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11
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A novel synthesis of functionalized sulfonamide derivatives using the reaction of substituted thiourea or oxime derivatives with N-(2,3-dibromopropyl)-aryl(alkyl)sulfonamides. MONATSHEFTE FUR CHEMIE 2022. [DOI: 10.1007/s00706-022-02991-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Kutateladze DA, Wagen CC, Jacobsen EN. Chloride-Mediated Alkene Activation Drives Enantioselective Thiourea and Hydrogen Chloride Co-Catalyzed Prins Cyclizations. J Am Chem Soc 2022; 144:15812-15824. [PMID: 35994741 PMCID: PMC9437134 DOI: 10.1021/jacs.2c06688] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The mechanism of chiral hydrogen-bond donor (HBD) and hydrogen chloride (HCl) co-catalyzed Prins cyclizations was analyzed through a combination of experimental and computational methods and revealed to involve an unexpected and previously unrecognized mode of alkene activation. Kinetic and spectroscopic studies support the participation of a catalytically active HCl·HBD complex that displays reduced Brønsted acidity relative to HCl alone. Nevertheless, rate acceleration relative to the HCl-catalyzed background reaction as well as high levels of enantioselectivity are achieved. This inverse Brønsted correlation is ascribed to chloride-mediated substrate activation in the rate-limiting and enantiodetermining cyclization transition state. Density functional theory (DFT) calculations, distortion-interaction analysis, and quasiclassical dynamics simulations support a stepwise mechanism in which rate acceleration and enantioselectivity are achieved through the precise positioning of the chloride anion within the active site of the chiral thiourea to enhance the nucleophilicity of the alkene and provide transition-state stabilization through local electric field effects. This mode of selective catalysis through anion positioning likely has general implications for the design of enantioselective Brønsted acid-catalyzed reactions involving π-nucleophiles.
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Affiliation(s)
| | | | - Eric N. Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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13
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Menke JM, Trapp O. Controlling the Enantioselectivity in an Adaptable Ligand by Biomimetic Intramolecular Interlocking. J Org Chem 2022; 87:11165-11171. [PMID: 35939525 DOI: 10.1021/acs.joc.2c01441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
For the preparation of chiral drugs, both stereochemically stable and flexible catalysts in combination with chiral auxiliaries can be used. Here, chiral induction plays an important role in generating an enantiomerically pure catalyst. We demonstrate a successful approach to the spontaneous deracemization of tropos ligands for asymmetric catalysis. Three different constitutional isomers of a bisphosphinite ligand decorated with l-valine moieties (interaction units) linked to the flexible biphenyl system by a phenylene bridge for inducing a chiral switch were prepared. The substitution pattern's influence on the attached intermolecular recognition sites was systematically investigated. We can show that biomimetic intramolecular hydrogen bonding leads to a pronounced diastereoselective enrichment of one of the ligand stereoisomers. As a result, in the asymmetric Rh-catalyzed hydrogenation of prochiral olefins using these ligands, enantiomeric ratios of up to 95.8:4.2 (S) were obtained. Of particular note is the inversion of enantioselectivity relative to the previously reported BIBIPHOS-Rh catalyst due to the altered orientation of the biphenyl moiety from (Rax) to (Sax). The enantioselectivities achieved by appropriate intramolecular interlocking are remarkable for a tropos ligand/catalyst. The strategy presented here represents a powerful approach for the spontaneous alignment of tropos ligands, yielding high enantioselectivities in asymmetric catalysis.
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Affiliation(s)
- Jan-Michael Menke
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany
| | - Oliver Trapp
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany
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14
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Bierschenk SM, Pan JY, Settineri NS, Warzok U, Bergman RG, Raymond KN, Toste FD. Impact of Host Flexibility on Selectivity in a Supramolecular Host-Catalyzed Enantioselective aza-Darzens Reaction. J Am Chem Soc 2022; 144:11425-11433. [PMID: 35700232 DOI: 10.1021/jacs.2c04182] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A highly enantioselective aza-Darzens reaction (up to 99% ee) catalyzed by an enantiopure supramolecular host has been discovered. To understand the role of host structure on reaction outcome, nine new gallium(III)-based enantiopure supramolecular assemblies were prepared via substitution of the external chiral amide. Despite the distal nature of the substitution in these catalysts, changes in enantioselectivity (61 to 90% ee) in the aziridine product were observed. The enantioselectivities were correlated to the flexibility of the supramolecular host scaffold as measured by the kinetics of exchange of a model cationic guest. This correlation led to the development of a best-in-class catalyst by substituting the gallium(III)-based host with one based on indium(III), which generated the most flexible and selective catalyst.
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Affiliation(s)
- Stephen M Bierschenk
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Judy Y Pan
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Nicholas S Settineri
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Ulrike Warzok
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Robert G Bergman
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kenneth N Raymond
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - F Dean Toste
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Chemistry, University of California, Berkeley, California 94720, United States
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15
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Entgelmeier LM, García Mancheño O. Activation Modes in Asymmetric Anion-Binding Catalysis. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/a-1846-6139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Over the past two decades, enantioselective anion-binding catalysis has emerged as a powerful strategy for the induction of chirality in organic transformations. The stereoselectivity is achieved in a range of different reactions by using non-covalent interactions between a chiral catalyst and an ionic substrate or intermediate, and subsequent formation of a chiral contact ion-pair upon anion-binding. This strategy offers vast possibilities in catalysis and the constant development of new reactions has led to various substrate activation approaches. This review provides an overview on the different activation modes in asymmetric anion-binding catalysis by looking at representative examples and recent advances made in this field.
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16
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Andres R, Wang Q, Zhu J. Catalytic Enantioselective Pictet-Spengler Reaction of α-Ketoamides Catalyzed by a Single H-Bond Donor Organocatalyst. Angew Chem Int Ed Engl 2022; 61:e202201788. [PMID: 35225416 PMCID: PMC9313548 DOI: 10.1002/anie.202201788] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Indexed: 01/17/2023]
Abstract
The asymmetric Pictet-Spengler reaction (PSR) with aldehydes is well known. However, PSR involving ketones as electrophilic partners is far-less developed. We report herein the first examples of catalytic enantioselective PSR of tryptamines with α-ketoamides. A new class of easily accessible prolyl-urea organocatalysts bearing a single H-bond donor function catalyzes the title reaction to afford 1,1-disubstituted tetrahydro-β-carbolines in excellent yields and enantioselectivities. The kinetic isotope effect using C2-deuterium-labelled tryptamine indicates that the rearomatization of the pentahydro-β-carbolinium ion intermediate might be the rate- and the enantioselectivity-determining step.
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Affiliation(s)
- Rémi Andres
- Laboratory of Synthesis and Natural ProductsInstitute of Chemical Sciences and EngineeringEcole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, 1015LausanneSwitzerland
| | - Qian Wang
- Laboratory of Synthesis and Natural ProductsInstitute of Chemical Sciences and EngineeringEcole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, 1015LausanneSwitzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural ProductsInstitute of Chemical Sciences and EngineeringEcole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, 1015LausanneSwitzerland
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17
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Andres R, Wang Q, Zhu J. Catalytic Enantioselective Pictet–Spengler Reaction of α‐Ketoamides Catalyzed by a Single H‐Bond Donor Organocatalyst. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Rémi Andres
- Laboratory of Synthesis and Natural Products Institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015 Lausanne Switzerland
| | - Qian Wang
- Laboratory of Synthesis and Natural Products Institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015 Lausanne Switzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural Products Institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015 Lausanne Switzerland
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18
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Wang XW, Huang WJ, Wang H, Wu B, Zhou YG. Chiral-Phosphoric-Acid-Catalyzed C6-Selective Pictet-Spengler Reactions for Construction of Polycyclic Indoles Containing Spiro Quaternary Stereocenters. Org Lett 2022; 24:1727-1731. [PMID: 35199528 DOI: 10.1021/acs.orglett.2c00368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Compared with the well-established asymmetric Pictet-Spengler reactions on the pyrrole ring of indoles, the catalytic asymmetric Pictet-Spengler reaction on the benzene ring of indoles has been rarely studied. Herein the C6-selective Pictet-Spengler reactions of indoles have been realized by employing 2-(1H-indol-7-yl)anilines and isatins in the presence of chiral phosphoric acid, affording novel polycyclic indole derivatives bearing spiro quaternary stereocenters in excellent yields with excellent enantioselectivities. This reaction could be conducted on the gram scale without any loss of activity or enantioselectivity.
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Affiliation(s)
- Xin-Wei Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China.,Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
| | - Wen-Jun Huang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Han Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Bo Wu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Yong-Gui Zhou
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China.,Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
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19
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Probst D, Manica M, Nana Teukam YG, Castrogiovanni A, Paratore F, Laino T. Biocatalysed synthesis planning using data-driven learning. Nat Commun 2022; 13:964. [PMID: 35181654 PMCID: PMC8857209 DOI: 10.1038/s41467-022-28536-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 01/25/2022] [Indexed: 01/30/2023] Open
Abstract
Enzyme catalysts are an integral part of green chemistry strategies towards a more sustainable and resource-efficient chemical synthesis. However, the use of biocatalysed reactions in retrosynthetic planning clashes with the difficulties in predicting the enzymatic activity on unreported substrates and enzyme-specific stereo- and regioselectivity. As of now, only rule-based systems support retrosynthetic planning using biocatalysis, while initial data-driven approaches are limited to forward predictions. Here, we extend the data-driven forward reaction as well as retrosynthetic pathway prediction models based on the Molecular Transformer architecture to biocatalysis. The enzymatic knowledge is learned from an extensive data set of publicly available biochemical reactions with the aid of a new class token scheme based on the enzyme commission classification number, which captures catalysis patterns among different enzymes belonging to the same hierarchy. The forward reaction prediction model (top-1 accuracy of 49.6%), the retrosynthetic pathway (top-1 single-step round-trip accuracy of 39.6%) and the curated data set are made publicly available to facilitate the adoption of enzymatic catalysis in the design of greener chemistry processes.
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Affiliation(s)
- Daniel Probst
- IBM Research Europe, CH-8803, Rüschlikon, Switzerland.
- National Center for Competence in Research-Catalysis (NCCR-Catalysis), Rüschlikon, Switzerland.
| | - Matteo Manica
- IBM Research Europe, CH-8803, Rüschlikon, Switzerland
| | | | - Alessandro Castrogiovanni
- IBM Research Europe, CH-8803, Rüschlikon, Switzerland
- National Center for Competence in Research-Catalysis (NCCR-Catalysis), Rüschlikon, Switzerland
| | | | - Teodoro Laino
- IBM Research Europe, CH-8803, Rüschlikon, Switzerland
- National Center for Competence in Research-Catalysis (NCCR-Catalysis), Rüschlikon, Switzerland
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20
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Nakamura S, Matsuda Y, Takehara T, Suzuki T. Enantioselective Pictet-Spengler Reaction of Acyclic α-Ketoesters Using Chiral Imidazoline-Phosphoric Acid Catalysts. Org Lett 2022; 24:1072-1076. [PMID: 35080408 DOI: 10.1021/acs.orglett.1c04316] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The first enantioselective Pictet-Spengler reaction of acyclic α-ketoesters with tryptamines has been developed. Excellent yields and enantioselectivity were obtained for the reaction using chiral imidazoline-phosphoric acid catalysts. Density functional theory calculations suggested possible transition states that explain the origin of chiral induction. This process provides an efficient route for the synthesis of tetrahydro-β-carboline derivatives.
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Affiliation(s)
- Shuichi Nakamura
- Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan.,Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Yoichiro Matsuda
- Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Tsunayoshi Takehara
- The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan
| | - Takeyuki Suzuki
- The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan
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21
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Kutateladze DA, Jacobsen EN. Cooperative Hydrogen-Bond-Donor Catalysis with Hydrogen Chloride Enables Highly Enantioselective Prins Cyclization Reactions. J Am Chem Soc 2021; 143:20077-20083. [PMID: 34812618 PMCID: PMC8717859 DOI: 10.1021/jacs.1c10890] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cooperative asymmetric catalysis with hydrogen chloride (HCl) and chiral dual-hydrogen-bond donors (HBDs) is applied successfully to highly enantioselective Prins cyclization reactions of a wide variety of simple alkenyl aldehydes. The optimal chiral catalysts were designed to withstand the strongly acidic reaction conditions and were found to induce rate accelerations of 2 orders of magnitude over reactions catalyzed by HCl alone. We propose that the combination of strong mineral acids and chiral hydrogen-bond-donor catalysts may represent a general strategy for inducing enantioselectivity in reactions that require highly acidic conditions.
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Affiliation(s)
- Dennis A. Kutateladze
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Eric N. Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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22
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Liang L, Zhou S, Zhang W, Tong R. Catalytic Asymmetric Alkynylation of 3,4-Dihydro-β-carbolinium Ions Enables Collective Total Syntheses of Indole Alkaloids. Angew Chem Int Ed Engl 2021; 60:25135-25142. [PMID: 34581483 DOI: 10.1002/anie.202112383] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Indexed: 12/21/2022]
Abstract
Chiral tetrahydro-β-carboline (THβC) is not only a prevailing structural feature of many natural alkaloids but also a versatile synthetic precursor for a vast array of monoterpenoid indole alkaloids. Asymmetric synthesis of C1-alkynyl THβCs remains rarely explored and challenging. Herein, we describe the development of two complementary approaches for the catalytic asymmetric alkynylation of 3,4-dihydro-β-carbolinium ions with up to 96 % yield and 99 % ee. The utility of chiral C1-alkynyl THβCs was demonstrated by the collective total syntheses of seven indole alkaloids: harmicine, eburnamonine, desethyleburnamonine, larutensine, geissoschizol, geissochizine, and akuammicine.
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Affiliation(s)
- Lixin Liang
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Shiqiang Zhou
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Wei Zhang
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Rongbiao Tong
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.,Hong Kong Branch of the Guangdong Southern Marine Science and Engineering Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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23
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Liang L, Zhou S, Zhang W, Tong R. Catalytic Asymmetric Alkynylation of 3,4‐Dihydro‐β‐carbolinium Ions Enables Collective Total Syntheses of Indole Alkaloids. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202112383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Lixin Liang
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong China
| | - Shiqiang Zhou
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong China
| | - Wei Zhang
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong China
| | - Rongbiao Tong
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong China
- Hong Kong Branch of the Guangdong Southern Marine Science and Engineering Laboratory (Guangzhou) The Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong China
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24
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Liu XY, Qin Y. Recent advances in the total synthesis of monoterpenoid indole alkaloids enabled by asymmetric catalysis. GREEN SYNTHESIS AND CATALYSIS 2021. [DOI: 10.1016/j.gresc.2021.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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25
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Neal MJ, Hejnosz SL, Rohde JJ, Evanseck JD, Montgomery TD. Multi-Ion Bridged Pathway of N-Oxides to 1,3-Dipole Dilithium Oxide Complexes. J Org Chem 2021; 86:11502-11518. [PMID: 34379424 DOI: 10.1021/acs.joc.1c01047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Roussi's landmark work on the generation of 1,3-dipoles from tertiary amine N-oxides has not reached its full potential since its underlying mechanism is neither well explored nor understood. Two competing mechanisms were previously proposed to explain the transformation involving either an iminium ion or a diradical intermediate. Our investigation has revealed an alternative mechanistic pathway that explains experimental results and provides significant insights to guide the creation of new N-oxide reagents beyond tertiary alkylamines for direct synthetic transformations. Truhlar's M06-2x functional and Møller-Plesset second-order perturbation theory with Dunning's [jul,aug]-cc-pv[D,T]z basis sets and discrete-continuum solvation models were employed to determine activation enthalpies and structures. During these mechanistic explorations, we discovered a unique multi-ion bridged pathway resulting from the rate-determining step, which was energetically more favorable than other alternate mechanisms. This newly proposed mechanism contains no electrophilic intermediates, strengthening the reaction potential by broadening the reagent scope and limiting the possible side reactions. This thoroughly defined general mechanism supports a more direct route for improving the use of N-oxides in generating azomethine ylide-dilithium oxide complexes with expanded functional group tolerance and breadth of chemistry.
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Affiliation(s)
- Martin J Neal
- Department of Chemistry and Biochemistry, Center for Computational Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
| | - Sarah L Hejnosz
- Department of Chemistry and Biochemistry, Center for Computational Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
| | - Jeffrey J Rohde
- Department of Chemistry, Physics, and Engineering, Franciscan University of Steubenville, 1235 University Boulevard, Steubenville, Ohio 43952, United States
| | - Jeffrey D Evanseck
- Department of Chemistry and Biochemistry, Center for Computational Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
| | - Thomas D Montgomery
- Department of Chemistry and Biochemistry, Center for Computational Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
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26
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Wu L, Qin L, Nie Y, Xu Y, Zhao YL. Computer-aided understanding and engineering of enzymatic selectivity. Biotechnol Adv 2021; 54:107793. [PMID: 34217814 DOI: 10.1016/j.biotechadv.2021.107793] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/26/2021] [Accepted: 06/28/2021] [Indexed: 12/26/2022]
Abstract
Enzymes offering chemo-, regio-, and stereoselectivity enable the asymmetric synthesis of high-value chiral molecules. Unfortunately, the drawback that naturally occurring enzymes are often inefficient or have undesired selectivity toward non-native substrates hinders the broadening of biocatalytic applications. To match the demands of specific selectivity in asymmetric synthesis, biochemists have implemented various computer-aided strategies in understanding and engineering enzymatic selectivity, diversifying the available repository of artificial enzymes. Here, given that the entire asymmetric catalytic cycle, involving precise interactions within the active pocket and substrate transport in the enzyme channel, could affect the enzymatic efficiency and selectivity, we presented a comprehensive overview of the computer-aided workflow for enzymatic selectivity. This review includes a mechanistic understanding of enzymatic selectivity based on quantum mechanical calculations, rational design of enzymatic selectivity guided by enzyme-substrate interactions, and enzymatic selectivity regulation via enzyme channel engineering. Finally, we discussed the computational paradigm for designing enzyme selectivity in silico to facilitate the advancement of asymmetric biosynthesis.
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Affiliation(s)
- Lunjie Wu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Lei Qin
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yao Nie
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Suqian Industrial Technology Research Institute of Jiangnan University, Suqian 223814, China.
| | - Yan Xu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
| | - Yi-Lei Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, MOE-LSB & MOE-LSC, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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27
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Kim A, Kim A, Park S, Kim S, Jo H, Ok KM, Lee SK, Song J, Kwon Y. Catalytic and Enantioselective Control of the C-N Stereogenic Axis via the Pictet-Spengler Reaction. Angew Chem Int Ed Engl 2021; 60:12279-12283. [PMID: 33651459 DOI: 10.1002/anie.202100363] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 02/16/2021] [Indexed: 12/11/2022]
Abstract
An unprecedented example of a chiral phosphoric acid-catalyzed atroposelective Pictet-Spengler reaction of N-arylindoles is reported. Highly enantioenriched N-aryl-tetrahydro-β-carbolines with C-N bond axial chirality are obtained via dynamic kinetic resolution. The hydrogen bond donor introduced on the bottom aromatic ring, forming a secondary interaction with the phosphoryl oxygen, is essential to achieving high enantioselectivity. A wide variety of substituents are tolerable with this transformation to provide up to 98 % ee. The application of electron-withdrawing group-substituted benzaldehydes enables the control of both axial and point stereogenicity. Biological evaluation of this new and unique scaffold shows promising antiproliferative activity and emphasizes the significance of atroposelective synthesis.
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Affiliation(s)
- Ahreum Kim
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
| | - Aram Kim
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
| | - Sunjung Park
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
| | - Sangji Kim
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
| | - Hongil Jo
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
| | - Kang Min Ok
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
| | - Sang Kook Lee
- College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, Republic of Korea
| | - Jayoung Song
- College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, Republic of Korea
| | - Yongseok Kwon
- Department of Chemistry, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul, Republic of Korea
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28
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Ronchi E, Paradine SM, Jacobsen EN. Enantioselective, Catalytic Multicomponent Synthesis of Homoallylic Amines Enabled by Hydrogen-Bonding and Dispersive Interactions. J Am Chem Soc 2021; 143:7272-7278. [PMID: 33949857 PMCID: PMC8547772 DOI: 10.1021/jacs.1c03024] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We report a one-step catalytic, enantioselective method for the preparation of homoallylic N-Boc amines directly from acetals. Reactive iminium ion intermediates are generated in situ through the combination of an acetal, a chiral thiourea catalyst, trialkylsilyl triflate, and N-Boc carbamate and are subsequently trapped by a variety of allylsilane nucleophiles. No homoallylic ether byproducts are detected, consistent with allylation of the iminium intermediate being highly favored over allylation of the intermediate oxocarbenium ion. Acetals derived from aromatic aldehydes possessing a variety of functional groups and substitution patterns yield homoallylic amines with excellent levels of enantiomeric enrichment. Experimental and computational data are consistent with an anchoring hydrogen-bond interaction between the protioiminium ion and the amide of the catalyst in the enantiodetermining transition state, and with stereodifferentiation achieved through specific noncovalent interactions (NCIs) with the catalyst pyrenyl moiety. Evidence is provided that the key NCI in the major pathway is a π-stacking interaction, contrasting with the cation-π interactions invoked in previously studied reactions promoted by the same family of aryl-pyrrolidino-H-bond-donor catalysts.
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Affiliation(s)
| | | | - Eric N. Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, United States
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29
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Kondo M, Matsuyama N, Aye TZ, Mattan I, Sato T, Makita Y, Ishibashi M, Arai MA, Takizawa S, Sasai H. Practical Stereoselective Synthesis of C3‐Spirooxindole‐ and C2‐Spiropseudoindoxyl‐Pyrrolidines
via
Organocatalyzed Pictet‐Spengler Reaction/Oxidative Rearrangement Sequence. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Masaru Kondo
- The Institute of Scientific and Industrial Research (ISIR) Osaka University Mihogaoka, Ibaraki-shi Osaka 567-0047 Japan
| | - Naoki Matsuyama
- The Institute of Scientific and Industrial Research (ISIR) Osaka University Mihogaoka, Ibaraki-shi Osaka 567-0047 Japan
| | - Tin Z. Aye
- The Institute of Scientific and Industrial Research (ISIR) Osaka University Mihogaoka, Ibaraki-shi Osaka 567-0047 Japan
| | - Irshad Mattan
- The Institute of Scientific and Industrial Research (ISIR) Osaka University Mihogaoka, Ibaraki-shi Osaka 567-0047 Japan
| | - Tomoyuki Sato
- Graduate School of Pharmaceutical Sciences Chiba University 1-8-1 Inohana, Chuo-ku Chiba 260-8675 Japan
| | - Yoshinori Makita
- Graduate School of Pharmaceutical Sciences Chiba University 1-8-1 Inohana, Chuo-ku Chiba 260-8675 Japan
- Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kohoku-ku Yokohama Kanagawa 223–8522 Japan
| | - Masami Ishibashi
- Graduate School of Pharmaceutical Sciences Chiba University 1-8-1 Inohana, Chuo-ku Chiba 260-8675 Japan
| | - Midori A. Arai
- Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kohoku-ku Yokohama Kanagawa 223–8522 Japan
| | - Shinobu Takizawa
- The Institute of Scientific and Industrial Research (ISIR) Osaka University Mihogaoka, Ibaraki-shi Osaka 567-0047 Japan
- Artificial Intelligence Research Center, ISIR Osaka University
| | - Hiroaki Sasai
- The Institute of Scientific and Industrial Research (ISIR) Osaka University Mihogaoka, Ibaraki-shi Osaka 567-0047 Japan
- Artificial Intelligence Research Center, ISIR Osaka University
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30
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Wang XW, Li X, Chen MW, Wu B, Zhou YG. Chiral Phosphoric Acid-Catalyzed Pictet-Spengler Reactions for Synthesis of 5',11'-Dihydrospiro[indoline-3,6'-indolo[3,2- c]qui-nolin]-2-ones Containing Quaternary Stereocenters. J Org Chem 2021; 86:6897-6906. [PMID: 33845579 DOI: 10.1021/acs.joc.1c00289] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chiral phosphoric acid-catalyzed Pictet-Spengler reactions of 2-(1H-indolyl)aniline derivatives and isatins by the condensation/cyclization process have been realized. A series of enantioenriched 5',11'-dihydrospiro[indoline-3,6'-indolo[3,2-c]quinolin]-2-ones bearing quaternary stereogenic centers were obtained with excellent yields and up to >99% ee. This protocol was suitable for the Pictet-Spengler reactions of 2-(1-benzyl-5-methyl-1H-pyrrol-2-yl)aniline, and a variety of 1',5'-dihydro-spiro[indoline-3,4'-pyrrolo[3,2-c]quinolin]-2-ones could also be obtained in good yields and up to 88% ee.
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Affiliation(s)
- Xin-Wei Wang
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China.,State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Xiang Li
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
| | - Mu-Wang Chen
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Bo Wu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Yong-Gui Zhou
- State Key Laboratory of Fine Chemicals, Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China.,State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
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31
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Non-Covalent Interactions in Enantioselective Organocatalysis: Theoretical and Mechanistic Studies of Reactions Mediated by Dual H-Bond Donors, Bifunctional Squaramides, Thioureas and Related Catalysts. Catalysts 2021. [DOI: 10.3390/catal11050569] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Chiral bifunctional dual H-bond donor catalysts have become one of the pillars of organocatalysis. They include squaramide, thiosquaramide, thiourea, urea, and even selenourea-based catalysts combined with chiral amines, cinchona alkaloids, sulfides, phosphines and more. They can promote several types of reactions affording products in very high yields and excellent stereoselectivities in many cases: conjugate additions, cycloadditions, the aldol and Henry reactions, the Morita–Baylis–Hilman reaction, even cascade reactions, among others. The desire to understand mechanisms and the quest for the origins of stereoselectivity, in attempts to find guidelines for developing more efficient catalysts for new transformations, has promoted many mechanistic and theoretical studies. In this review, we survey the literature published in this area since 2015.
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32
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Kim A, Kim A, Park S, Kim S, Jo H, Ok KM, Lee SK, Song J, Kwon Y. Catalytic and Enantioselective Control of the C–N Stereogenic Axis via the Pictet–Spengler Reaction. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202100363] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Ahreum Kim
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
| | - Aram Kim
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
| | - Sunjung Park
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
| | - Sangji Kim
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
| | - Hongil Jo
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
| | - Kang Min Ok
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
| | - Sang Kook Lee
- College of Pharmacy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul Republic of Korea
| | - Jayoung Song
- College of Pharmacy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul Republic of Korea
| | - Yongseok Kwon
- Department of Chemistry Sogang University 35 Baekbeom-ro, Mapo-gu Seoul Republic of Korea
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33
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Lynch-Colameta T, Greta S, Snyder SA. Synthesis of aza-quaternary centers via Pictet-Spengler reactions of ketonitrones. Chem Sci 2021; 12:6181-6187. [PMID: 33996016 PMCID: PMC8098696 DOI: 10.1039/d1sc00882j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 03/12/2021] [Indexed: 01/25/2023] Open
Abstract
Despite the array of advances that have been made in Pictet-Spengler chemistry, particularly as it relates to the synthesis of β-carboline derivatives of both natural and designed origin, the ability to use such reactions to generate aza-quaternary centers remains limited. Herein, we report a simple procedure that enables the synthesis of a variety of such products by harnessing the distinct reactivity profiles of ketonitrones as activated by commercially available acyl chlorides. Notably, the reaction process is mild, fast, and high-yielding (54-97%) for a diverse collection of substrates, including some typically challenging ones, such as indole cores with electron-deficient substituents. In addition, by deploying an acyl bromide in combination with a thiourea promoter, a catalytic, asymmetric version has been established, leading to good levels of enantioselectivity (up to 83% ee) for several ketonitrones. Finally, the resultant N-O bonds within the products can also be functionalized in several unique ways, affording valuable complementarity to existing Pictet-Spengler variants based on the use of imines.
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Affiliation(s)
- Tessa Lynch-Colameta
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
| | - Sarah Greta
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
| | - Scott A Snyder
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
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34
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Retini M, Bartoccini F, Zappia G, Piersanti G. Novel, Chiral, and Enantiopure C
2
‐Symmetric Thioureas Promote Asymmetric Protio‐Pictet‐Spengler Reactions by Anion‐Binding Catalysis. European J Org Chem 2021. [DOI: 10.1002/ejoc.202001501] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Michele Retini
- Dipartimento di Scienze Biomolecolari Università degli studi di Urbino Carlo Bo P.zza del Rinascimento 6 61029 Urbino Italy
| | - Francesca Bartoccini
- Dipartimento di Scienze Biomolecolari Università degli studi di Urbino Carlo Bo P.zza del Rinascimento 6 61029 Urbino Italy
| | - Giovanni Zappia
- Dipartimento di Scienze Biomolecolari Università degli studi di Urbino Carlo Bo P.zza del Rinascimento 6 61029 Urbino Italy
| | - Giovanni Piersanti
- Dipartimento di Scienze Biomolecolari Università degli studi di Urbino Carlo Bo P.zza del Rinascimento 6 61029 Urbino Italy
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35
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Li M, Zhang S, Zhang X, Wang Y, Chen J, Tao Y, Wang X. Unimolecular Anion‐Binding Catalysts for Selective Ring‐Opening Polymerization of
O
‐carboxyanhydrides. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011352] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Maosheng Li
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Shuai Zhang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Xiaoyong Zhang
- Department of Chemistry KU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Yanchao Wang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Jinlong Chen
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Youhua Tao
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Xianhong Wang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
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36
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Li M, Zhang S, Zhang X, Wang Y, Chen J, Tao Y, Wang X. Unimolecular Anion‐Binding Catalysts for Selective Ring‐Opening Polymerization of
O
‐carboxyanhydrides. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/anie.202011352] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Maosheng Li
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Shuai Zhang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Xiaoyong Zhang
- Department of Chemistry KU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Yanchao Wang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Jinlong Chen
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Youhua Tao
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
| | - Xianhong Wang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China
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37
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Matador E, Retamosa MDG, Rohal'ová D, Iglesias-Sigüenza J, Merino P, Fernández R, Lassaletta JM, Monge D. α-Keto hydrazones in asymmetric aminocatalysis: reactivity through β-amino aza-dienamine intermediates. Org Chem Front 2021. [DOI: 10.1039/d1qo00384d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
α-keto hydrazones activated by a bifunctional amino-thiourea catalyst generate β-amino aza-dienamine intermediates which react with nitroalkenes in highly enantioselective fashion.
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Affiliation(s)
- Esteban Matador
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - María de Gracia Retamosa
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - Dominika Rohal'ová
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - Javier Iglesias-Sigüenza
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - Pedro Merino
- Instituto de Biocomputación y Física de Sistemas Complejos (BIFI). Universidad de Zaragoza
- 50009 Zaragoza
- Spain
| | - Rosario Fernández
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
| | - José M. Lassaletta
- Instituto de Investigaciones Químicas (CSIC-US) and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41092 Sevilla
- Spain
| | - David Monge
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA)
- 41012 Sevilla
- Spain
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38
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Xiao X, Shao B, Lu Y, Cao Q, Xia C, Chen F. Recent Advances in Asymmetric Organomulticatalysis. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000961] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Xiao Xiao
- Institute of Pharmaceutical Science and Technology Zhejiang University of Technology Hangzhou 310014 People's Republic China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of Technology Hangzhou 310014 People's Republic China
| | - Bing‐Xuan Shao
- Institute of Pharmaceutical Science and Technology Zhejiang University of Technology Hangzhou 310014 People's Republic China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of Technology Hangzhou 310014 People's Republic China
| | - Yin‐Jie Lu
- Institute of Pharmaceutical Science and Technology Zhejiang University of Technology Hangzhou 310014 People's Republic China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of Technology Hangzhou 310014 People's Republic China
| | - Qian‐Qian Cao
- Institute of Pharmaceutical Science and Technology Zhejiang University of Technology Hangzhou 310014 People's Republic China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of Technology Hangzhou 310014 People's Republic China
| | - Chun‐Nian Xia
- Institute of Pharmaceutical Science and Technology Zhejiang University of Technology Hangzhou 310014 People's Republic China
| | - Fen‐Er Chen
- Institute of Pharmaceutical Science and Technology Zhejiang University of Technology Hangzhou 310014 People's Republic China
- Engineering Center of Catalysis and Synthesis for Chiral Molecules Fudan University Shanghai 200433 People's Republic China
- Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433 People's Republic China
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39
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Ong DY, Chen JH, Chiba S. Reductive Functionalization of Carboxamides: A Recent Update. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2020. [DOI: 10.1246/bcsj.20200182] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Derek Yiren Ong
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Jia-hua Chen
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Shunsuke Chiba
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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40
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Nickisch R, Gabrielsen SM, Meier MAR. Novel Access to Known and Unknown Thiourea Catalyst via a Multicomponent‐Reaction Approach. ChemistrySelect 2020. [DOI: 10.1002/slct.202003336] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Roman Nickisch
- Institute of Organic Chemistry Karlsruhe Institute of Technology (KIT) Straße am Forum 7 76131 Karlsruhe Germany
| | - Solveig M. Gabrielsen
- Institute of Organic Chemistry Karlsruhe Institute of Technology (KIT) Straße am Forum 7 76131 Karlsruhe Germany
| | - Michael A R. Meier
- Institute of Organic Chemistry Karlsruhe Institute of Technology (KIT) Straße am Forum 7 76131 Karlsruhe Germany
- Institute of Biological and Chemical Systems – Functional Molecular Systems (IBCS-FMS) Karlsruhe Institute of Technology (KIT) Straße am Forum 7 76131 Karlsruhe Germany
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41
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Metternich JB, Reiterer M, Jacobsen EN. Asymmetric Nazarov Cyclizations of Unactivated Dienones by Hydrogen-Bond-Donor/Lewis Acid Co-Catalyzed, Enantioselective Proton-Transfer. Adv Synth Catal 2020; 362:4092-4097. [PMID: 33162875 PMCID: PMC7643875 DOI: 10.1002/adsc.202000831] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Indexed: 12/15/2022]
Abstract
We report an enantioselective Nazarov cyclization catalyzed by chiral hydrogen-bond-donors in concert with silyl Lewis acids. The developed transformation provides access to tri-substituted cyclopentenones in high levels of enantioselectivity (up to 95% e.e.) from a variety of simple unactivated dienones. Kinetic and mechanistic studies are consistent with a reversible 4π-electrocyclization C-C bond-forming step followed by rate- and enantio-determining proton-transfer as the mode of catalysis.
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Affiliation(s)
- Jan B Metternich
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Martin Reiterer
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Eric N Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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42
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Li X, Sun J. Organocatalytic Enantioselective Synthesis of Chiral Allenes: Remote Asymmetric 1,8‐Addition of Indole Imine Methides. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202006137] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xingguang Li
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
| | - Jianwei Sun
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
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43
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Li X, Sun J. Organocatalytic Enantioselective Synthesis of Chiral Allenes: Remote Asymmetric 1,8‐Addition of Indole Imine Methides. Angew Chem Int Ed Engl 2020; 59:17049-17054. [DOI: 10.1002/anie.202006137] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Indexed: 11/09/2022]
Affiliation(s)
- Xingguang Li
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
| | - Jianwei Sun
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
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44
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Maskeri MA, Brueckner AC, Feoktistova T, O'Connor MJ, Walden DM, Cheong PHY, Scheidt KA. Mechanism and origins of selectivity in the enantioselective oxa-Pictet-Spengler reaction: a cooperative catalytic complex from a hydrogen bond donor and chiral phosphoric acid. Chem Sci 2020; 11:8736-8743. [PMID: 34123127 PMCID: PMC8163393 DOI: 10.1039/d0sc03250f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 07/21/2020] [Indexed: 11/29/2022] Open
Abstract
Enantioselective additions to oxocarbenium ions are high-value synthetic transformations but have proven challenging to achieve. In particular, the oxa-Pictet-Spengler reaction has only recently been rendered enantioselective. We report experimental and computational studies on the mechanism of this unusual transformation. Herein we reveal that this reaction is hypothesized to proceed through a self-assembled ternary hydrogen bonding complex involving the substrate, chiral phosphate ion, and a urea hydrogen-bond donor. The computed transition state reveals C2-symmetric grooves in the chiral phosphate that are occupied by the urea and substrate. Occupation of one of these grooves by the urea co-catalyst tunes the available reactive volume and enhances the stereoselectivity of the chiral phosphate catalyst.
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Affiliation(s)
- Mark A Maskeri
- Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Northwestern University Evanston IL 60208 USA
| | | | | | - Matthew J O'Connor
- Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Northwestern University Evanston IL 60208 USA
| | - Daniel M Walden
- Department of Chemistry, Oregon State University Corvallis OR 97331 USA
| | | | - Karl A Scheidt
- Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Northwestern University Evanston IL 60208 USA
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45
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Andres R, Wang Q, Zhu J. Asymmetric Total Synthesis of (−)-Arborisidine and (−)-19-epi-Arborisidine Enabled by a Catalytic Enantioselective Pictet–Spengler Reaction. J Am Chem Soc 2020; 142:14276-14285. [DOI: 10.1021/jacs.0c05804] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Rémi Andres
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN BCH5304, CH-1015 Lausanne, Switzerland
| | - Qian Wang
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN BCH5304, CH-1015 Lausanne, Switzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN BCH5304, CH-1015 Lausanne, Switzerland
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46
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Liao MH, Zhang M, Hu DH, Zhang RH, Zhao Y, Liu SS, Li YX, Xiao WL, Tang E. Controlling the selectivity of an intramolecular Friedel-Crafts alkylation with alkenes using selenium under mild conditions. Org Biomol Chem 2020; 18:4034-4045. [PMID: 32191248 DOI: 10.1039/d0ob00257g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficiently divergent intramolecular Friedel-Crafts alkylation by unactivated alkenes with seleniranium ion-controlled Markovnikov/anti-Markovnikov specificities under mild conditions has been investigated. 2-Benzoxepin, isochroman, and isochromene can be produced in one-pot procedures from the same substrate in high yields and with high regio- and stereospecificity. The products are challenging to access via 7-endo-trig carbocyclizations and by 7-endo-trig carbocyclization/rearrangement/6-exo-trig oxycyclization and 6-exo-trig carbocyclization/deselenenylation reaction sequences, respectively. Mechanistic experiments indicated that in addition to the stereospecific anti-addition processes of the cyclization reactions, the formation of a stable carbocation after ring opening of the seleniranium ion leads to an NPSP-mediated 7-endo-trig carbocyclization; the steric hindrance of the seleniranium intermediate controls the regioselectivity when using TPSCA at 60 °C, which promotes 6-exo-trig carbocyclization. Two distinct catalytic cycles were proposed, and the structures of transition states and products were identified by ab initio calculations and X-ray analyses.
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Affiliation(s)
- Ming-Hong Liao
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming, 650091 China.
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Uraguchi D, Ueoka F, Tanaka N, Kizu T, Takahashi W, Ooi T. A Structurally Robust Chiral Borate Ion: Molecular Design, Synthesis, and Asymmetric Catalysis. Angew Chem Int Ed Engl 2020; 59:11456-11461. [DOI: 10.1002/anie.202001637] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/12/2020] [Indexed: 02/02/2023]
Affiliation(s)
- Daisuke Uraguchi
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Fumito Ueoka
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Naoya Tanaka
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Tomohito Kizu
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Wakana Takahashi
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Takashi Ooi
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM) Nagoya University Nagoya 464-8601 Japan
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Uraguchi D, Ueoka F, Tanaka N, Kizu T, Takahashi W, Ooi T. A Structurally Robust Chiral Borate Ion: Molecular Design, Synthesis, and Asymmetric Catalysis. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Daisuke Uraguchi
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Fumito Ueoka
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Naoya Tanaka
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Tomohito Kizu
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Wakana Takahashi
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
| | - Takashi Ooi
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University Nagoya 464-8603 Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM) Nagoya University Nagoya 464-8601 Japan
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Zheng C, You SL. Exploring the Chemistry of Spiroindolenines by Mechanistically-Driven Reaction Development: Asymmetric Pictet-Spengler-type Reactions and Beyond. Acc Chem Res 2020; 53:974-987. [PMID: 32275392 DOI: 10.1021/acs.accounts.0c00074] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The Pictet-Spengler reaction is a fundamental named reaction in organic chemistry, and it is the most straightforward method for the synthesis of tetrahydro-β-carbolines, a core structure embedded in numerous alkaloids. Spiroindolenines are often proposed as possible intermediates in Pictet-Spengler reactions. However, whether the spiroindolenine species is an intermediate in the mechanism of the asymmetric Pictet-Spengler reaction remains unclear. Questions about the role of the spiroindolenine species regarding the mechanism include the following: Can the spiroindolenine species be formed effectively under Pictet-Spengler conditions? If so, what is its fate? Is the delivery of the enantioenriched tetrahydro-β-carboline product related to the spiroindolenine intermediate? Previous studies regarding these questions have not reached a consensus. Therefore, elucidating these questions will advance the field of synthetic organic chemistry.The first highly enantioselective synthesis of spiroindolenines that have the same molecular scaffold as the proposed key intermediate of the Pictet-Spengler reaction was accomplished by an Ir-catalyzed intramolecular asymmetric allylic substitution reaction of an indol-3-yl allylic carbonate. In this reaction, a piperidine, pyrrolidine, or cyclopentane ring can be introduced in conjunction with the indolenine structure.Spiroindolenines were found to undergo ring-expansive migration reactions when treated with a catalytic amount of an acid, leading to tetrahydro-β-carbolines or related tetrahydrocarbazoles. Comprehensive DFT calculations and Born-Oppenheimer molecular dynamics simulations have provided insight into the mechanism of the migration process. It has been found that the stereochemistry is strongly correlated with the electronic properties of the migratory group along with the acidity of the catalyst. Close interactions between the positively charged migratory group and the electron-rich indole ring favor the stereospecificity of the migration. Furthermore, a continuous mechanistic spectrum of the Pictet-Spengler reactions can be obtained on the basis of two readily accessible energetic parameters that are derived from computed energies for competing transition states relative to a key intermediate species. This theoretical model provides a unified mechanistic understanding of the asymmetric Pictet-Spengler reaction, which has been further supported by rationally designed prototype reactions. Chemically and stereochemically controllable migration can be achieved when multiple potential migratory groups are available.The reactivity of spiroindolenines has also been explored beyond Pictet-Spengler reactions. A one-pot Ir-catalyzed asymmetric allylic dearomatization/stereoconvergent migration allows the facile synthesis of enantioenriched tetrahydro-β-carbolines from racemic starting materials. An unprecedented six- to seven-membered ring-expansive migration can be achieved when a vinyliminium moiety is involved as a highly reactive migratory group. This reaction facilitates the stereoselective synthesis of thermodynamically challenging indole-annulated seven-membered rings. It has also been found that the migration process can be interrupted. The electrophilic migratory group released from the retro-Mannich reaction of a spiroindolenine can be captured by an inter- or intramolecular nucleophile, thus providing new entries into structurally diverse polycyclic indole derivatives.Therefore, the mechanism of the Pictet-Spengler reaction can be probed by manipulating the reactivity of the spiroindolenine species. In turn, the mechanistic insights gained herein will aid in chemical transformations toward various target molecules. This study serves as a vivid example of the positive interplay between experimental and theoretical investigations in synthetic organic chemistry.
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Affiliation(s)
- Chao Zheng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Shu-Li You
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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Lin Y, Hirschi WJ, Kunadia A, Paul A, Ghiviriga I, Abboud KA, Karugu RW, Vetticatt MJ, Hirschi JS, Seidel D. A Selenourea-Thiourea Brønsted Acid Catalyst Facilitates Asymmetric Conjugate Additions of Amines to α,β-Unsaturated Esters. J Am Chem Soc 2020; 142:5627-5635. [PMID: 32118419 PMCID: PMC7533150 DOI: 10.1021/jacs.9b12457] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
β-Amino esters are obtained with high levels of enantioselectivity via the conjugate addition of cyclic amines to unactivated α,β-unsaturated esters. A related strategy enables the kinetic resolution of racemic cyclic 2-arylamines, using benzyl acrylate as the resolving agent. Reactions are facilitated by an unprecedented selenourea-thiourea organocatalyst. As elucidated by DFT calculations and 13C kinetic isotope effect studies, the rate-limiting and enantiodetermining step of the reaction is the protonation of a zwitterionic intermediate by the catalyst. This represents a rare case in which a thiourea compound functions as an asymmetric Brønsted acid catalyst.
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Affiliation(s)
- Yingfu Lin
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - William J Hirschi
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Anuj Kunadia
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Anirudra Paul
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Ion Ghiviriga
- Center for NMR Spectroscopy, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Khalil A Abboud
- Center for X-ray Crystallography, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Rachael W Karugu
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Mathew J Vetticatt
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Jennifer S Hirschi
- Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States
| | - Daniel Seidel
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
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