1
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Ren X, Duan XY, Feng Y, Li Y, Li J, Qi J. Highly Enantioselective Synthesis of Polycyclic Dihydroisoquinolinones via NHC-Catalyzed [4 + 2] Annulations. J Org Chem 2024; 89:14135-14140. [PMID: 39267456 DOI: 10.1021/acs.joc.4c01529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/17/2024]
Abstract
The NHC-catalyzed enantioselective [4 + 2] annulation of 9H-fluorene-1-carbaldenydes with cyclic imines was successfully developed. A series of optically enriched polycyclic dihydroisoquinolinones were synthesized in moderate to excellent yields with good to excellent enantioselectivities. In addition, this efficient method could also be amenable to the synthesis of spirocyclic compounds by using isatin-derived ketimines as the electrophiles.
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Affiliation(s)
- Xiaojie Ren
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Hebei University, Baoding 071002, China
| | - Xiao-Yong Duan
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Hebei University, Baoding 071002, China
- State Key Laboratory of New Pharmaceutical Preparations and Excipients, College of Chemistry and Materials Science, Hebei University, Baoding 071002, China
| | - Yuxuan Feng
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Hebei University, Baoding 071002, China
| | - Yanting Li
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Hebei University, Baoding 071002, China
| | - Jiahan Li
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Hebei University, Baoding 071002, China
| | - Jing Qi
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Hebei University, Baoding 071002, China
- State Key Laboratory of New Pharmaceutical Preparations and Excipients, College of Chemistry and Materials Science, Hebei University, Baoding 071002, China
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2
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Feng S, Zhang H, Liu J, Shi D, Yang W, Zhu H, Zhang X, Fu Z. Carbene-Catalyzed [3 + 3] Annulation of Enals and Vinyl Sulfoxonium Ylides. J Org Chem 2024; 89:14537-14542. [PMID: 39323184 DOI: 10.1021/acs.joc.4c01587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/27/2024]
Abstract
Carbene-catalyzed [3 + 3] annulation of enals and vinyl sulfoxonium ylides has been demonstrated. This method efficiently synthesizes a range of 2-sulfenylidene-3-cyclohexen-1-ones with high atom economy. Notably, the presence of the sulfoxonium ylide moiety in the obtained products significantly enhances their potential for further synthetic transformations.
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Affiliation(s)
- Siru Feng
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
| | - Hailong Zhang
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
| | - Jinhua Liu
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
| | - Dongping Shi
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
| | - Weiqi Yang
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
| | - Haibin Zhu
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
| | - Xiaoxiang Zhang
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Zhenqian Fu
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
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3
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Wang ZY, Ma G, Xu Y, Wang Q, Zhang M, Ma X, Ma C, Sun A, Xia R, Liu H. One-pot synthesis of functionalized dihydropyridin-2-ones via carbene-catalyzed base-controlled [3+3] annulation reaction. Chem Commun (Camb) 2024; 60:11327-11330. [PMID: 39297768 DOI: 10.1039/d4cc03521f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2024]
Abstract
Herein, we have described a novel organocatalytic approach to access biologically important dihydropyridin-2-ones in a one-pot way with generally high yields (up to 99%) and excellent enantioselectivities (up to 99% ee). This reaction proceeded via a new dual activation mode, including in situ-generated α,β-unsaturated acylazoliums and 4-dimethylaminopyridinium salts that underwent a Michael addition/1,4-H migration/lactamization sequence. The base-triggered 4-dimethylaminopyridinium ylide formation pathway over the competing substitution reaction pathway of vicinal haloamines is noteworthy.
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Affiliation(s)
- Zhan-Yong Wang
- School of Pharmacy, Xinxiang University, Xinxiang 453003, China.
| | - Guoyang Ma
- School of Chemistry and Materials Engineering, Xinxiang University, Xinxiang 453003, China
| | - Yaoyao Xu
- School of Pharmacy, Xinxiang University, Xinxiang 453003, China.
| | - Qingqing Wang
- School of Pharmacy, Xinxiang University, Xinxiang 453003, China.
| | - Mengru Zhang
- School of Pharmacy, Xinxiang University, Xinxiang 453003, China.
| | - Xueji Ma
- School of Pharmacy, Xinxiang University, Xinxiang 453003, China.
| | - Chenyang Ma
- Henan Run Catalysts Co., Ltd, Xinxiang 453003, China
| | - Aili Sun
- Puyang Institute of Technology, Henan University, Puyang 457000, China
| | - Ran Xia
- School of Pharmacy, Xinxiang University, Xinxiang 453003, China.
| | - Hongxin Liu
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China.
- Institute of New Materials & Industrial Technology, Wenzhou University, Wenzhou 325035, China.
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4
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Zhang ZF, Zhang CL, Ye S. N-Heterocyclic Carbene/Transition Metal Dual Catalysis. Chemistry 2024; 30:e202402259. [PMID: 39013831 DOI: 10.1002/chem.202402259] [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: 06/12/2024] [Revised: 07/16/2024] [Accepted: 07/16/2024] [Indexed: 07/18/2024]
Abstract
N-heterocyclic carbene catalysis has been developed as a versatile method for the enantioselective synthesis of complex organic molecules in organic chemistry. Merging of N-heterocyclic carbene catalysis with transition metal catalysis holds the potential to achieve unprecedented transformations with broad substrate scope and excellent stereoselectivity, which are unfeasible with individual catalyst. Thus, this dual catalysis has attracted increasing attention, and numerous elegant dual catalytic systems have been established. In this review, we summarize the recent achievements of dual NHC/transition metal catalysis, including the reaction design, mechanistic studies and practical applications.
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Affiliation(s)
- Zhao-Fei Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Chun-Lin Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Song Ye
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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5
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Li E, Liao X, Guo F, Huang Y, Chen J. N-Heterocyclic Carbene-Catalyzed Asymmetric S N2 Alkylation via Noncovalent Activation. Org Lett 2024; 26:7479-7483. [PMID: 39092835 DOI: 10.1021/acs.orglett.4c02082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
The field of asymmetric catalysis has been developed by exploring noncovalent interactions, particularly within N-heterocyclic carbene-mediated processes. Despite challenges due to the limited number of compatible electrophiles (predominantly π-acceptors), this study introduces the first asymmetric α-alkylation of 3-aryl oxindoles using Csp3 electrophiles. The innovative protocol integrates diverse oxindoles and alkyl, allyl, and propargyl electrophiles, achieving high yields and enantioselectivities. Preliminary mechanistic explorations support a noncovalent catalytic mechanism, enhancing the tool kit for constructing complex chiral molecules with potential applications.
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Affiliation(s)
- En Li
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, China
| | - Xiaoyun Liao
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, China
| | - Fangfang Guo
- State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yong Huang
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong SAR, China
| | - Jiean Chen
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, China
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6
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Li B, Hu J, Liao M, Xiong Q, Zhang Y, Chi YR, Zhang X, Wu X. Catalyst Control over S(IV)-stereogenicity via Carbene-derived Sulfinyl Azolium Intermediates. J Am Chem Soc 2024; 146:25350-25360. [PMID: 39219070 DOI: 10.1021/jacs.4c10486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Stereoselective synthesis utilizing small-molecule catalysts, particularly N-heterocyclic carbene (NHC), has facilitated swift access to enantioenriched molecules through diverse activation modes and NHC-bound reactive intermediates. While carbonyl derivatives, imines, and "activated" alkenes have been extensively investigated, the exploration of heteroatom-centered analogues of NHC-bound intermediates has long been neglected, despite the significant potential for novel chemical transformations they offer once recognized. Herein, we disclose a carbene-catalyzed new activation mode by generating unique sulfinyl azolium intermediates from carbene nucleophilic addition to in situ-generated mixed sulfinic anhydride intermediates. Combined experimental and computational mechanistic investigations pinpoint the chiral NHC-catalyzed formation of sulfinyl azolium intermediate as the enantio-determining step. The novel "S"-based carbene reactive intermediate imparts high efficiency for the catalytic construction of sulfur-stereogenic compounds, giving rise to sulfinate esters with high yields and enantioselectivities under mild conditions. Notably, distinct from most of the NHC-catalyzed enantioselective transformations focusing on the "C" central chiral products, our study realizes a unique carbene-catalyst control over chiral "S" stereocenters via direct asymmetric S-O bond formation for the first time. Furthermore, these sulfinyl-containing products could serve as versatile synthetic platforms for enantioenriched S-stereogenic functional molecules and exhibit remarkable antibacterial activities against rice plant pathogens, which is valuable for the development of novel agrochemical agents.
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Affiliation(s)
- Benpeng Li
- State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
- School of Life and Health Science, Kaili University, Kaili 556011, China
| | - Junyuan Hu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Minghong Liao
- State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Qin Xiong
- State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Yaqi Zhang
- State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Yonggui Robin Chi
- State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, Singapore 637371, Singapore
| | - Xinglong Zhang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #16-16, Connexis, Singapore 138632, Singapore
| | - Xingxing Wu
- State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
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7
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Yu M, Huang J, Zhu H, Shi D, Yang W, Liu Y, Ji Y, Fu Z. Facile construction of 2-pyrones under carbene catalysis. RSC Adv 2024; 14:28585-28595. [PMID: 39247504 PMCID: PMC11378031 DOI: 10.1039/d4ra05596a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2024] [Accepted: 09/02/2024] [Indexed: 09/10/2024] Open
Abstract
2-Pyrones are valuable structural motifs in organic chemistry, found in numerous natural products and pharmaceuticals. The synthesis of these heterocycles has been significantly advanced by the application of N-Heterocyclic Carbene (NHC) catalysis. This review examines the recent advancements in NHC-catalyzed synthesis of 2-pyrones, highlighting key methodologies, mechanisms, and synthetic applications. NHC catalysis has revolutionized the synthesis of 2-pyrones, providing efficient, selective, and versatile methods for constructing these valuable heterocycles.
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Affiliation(s)
- Miao Yu
- Engineering Research Center for Medicine, Ministry of Education, Harbin University of Commerce Harbin 150076 China
| | - Jie Huang
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering & Institute of Advanced Materials, Nanjing Tech University 30 South Puzhu Road Nanjing 211816 China
| | - Haibin Zhu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering & Institute of Advanced Materials, Nanjing Tech University 30 South Puzhu Road Nanjing 211816 China
| | - Dongping Shi
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering & Institute of Advanced Materials, Nanjing Tech University 30 South Puzhu Road Nanjing 211816 China
| | - Weiqi Yang
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering & Institute of Advanced Materials, Nanjing Tech University 30 South Puzhu Road Nanjing 211816 China
| | - Yingjie Liu
- Engineering Research Center for Medicine, Ministry of Education, Harbin University of Commerce Harbin 150076 China
| | - Yubin Ji
- Engineering Research Center for Medicine, Ministry of Education, Harbin University of Commerce Harbin 150076 China
| | - Zhenqian Fu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering & Institute of Advanced Materials, Nanjing Tech University 30 South Puzhu Road Nanjing 211816 China
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8
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Ye ZT, Wu ZW, Zhang XX, Zhou J, Yu JS. Organocatalytic enantioselective construction of Si-stereocenters: recent advances and perspectives. Chem Soc Rev 2024; 53:8546-8562. [PMID: 39091219 DOI: 10.1039/d4cs00417e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Silicon-stereogenic chiral organosilanes have found increasing applications in synthetic chemistry, medicinal chemistry, and materials science. In this context, various asymmetric catalytic methods have been established for the diverse synthesis of silicon-stereogenic silanes. In particular, asymmetric organocatalysis is emerging as an important and complementary synthetic tool for the enantioselective construction of silicon-stereocenters, along with the rapid development of chiral-metal catalyzed protocols. Its advent provides a powerful platform to achieve functionalized silicon-stereogenic organosilanes with structural diversity, and should lead to great development in chiral organosilicon chemistry. In this Tutorial Review, we highlight these latest achievements from two aspects: desymmetrizations of prochiral tetraorganosilanes and dynamic kinetic asymmetric transformations of racemic organosilanes by employing five organocatalytic activation modes. The advantages, limitations and synthetic value of each protocol, as well as the synthetic opportunities still open for further exploration, are also discussed.
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Affiliation(s)
- Zhong-Tian Ye
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.
| | - Zhong-Wei Wu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.
| | - Xue-Xin Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.
| | - Jian Zhou
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.
| | - Jin-Sheng Yu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.
- Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, Hainan Normal University, Haikou 571158, P. R. China
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9
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Dočekal V, Niderer Y, Kurčina A, Císařová I, Veselý J. Regio- and Enantioselective N-Heterocyclic Carbene-Catalyzed Annulation of Aminoindoles Initiated by Friedel-Crafts Alkylation. Org Lett 2024; 26:6993-6998. [PMID: 39115978 PMCID: PMC11348421 DOI: 10.1021/acs.orglett.4c02434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2024] [Revised: 07/31/2024] [Accepted: 08/05/2024] [Indexed: 08/10/2024]
Abstract
Chiral indoles annulated on the benzene ring are unique and significant in natural and medicinal compounds. However, accessing these enantioenriched molecules has often been overlooked. The present study introduces an organocatalytic protocol to access these compounds efficiently, demonstrated by substrate scope, functional group tolerance, and using only 1 mol % of a chiral conjugated acid catalyst. Additionally, the study explores regioselectivity, gram-scale reactions, and follow-up transformations, underscoring the method's potential.
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Affiliation(s)
- Vojtěch Dočekal
- Department
of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague 2, Czech Republic
| | - Yaroslava Niderer
- Department
of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague 2, Czech Republic
- Faculty
of Sciences, Aix-Marseille University, 52 Av. Escadrille Normandie Niemen, 13013 Marseille, France
| | - Adam Kurčina
- Department
of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague 2, Czech Republic
| | - Ivana Císařová
- Department
of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague 2, Czech Republic
| | - Jan Veselý
- Department
of Organic Chemistry, Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague 2, Czech Republic
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10
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Lu F, Su F, Pan S, Wu X, Wu X, Chi YR. N-Heterocyclic Carbene Enabled Functionalization of Inert C(Sp 3)-H Bonds via Hydrogen Atom Transfer (HAT) Processes. Chemistry 2024; 30:e202401811. [PMID: 39092881 DOI: 10.1002/chem.202401811] [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: 05/08/2024] [Indexed: 08/04/2024]
Abstract
Developing methods to directly transform C(sp3) -H bonds is crucial in synthetic chemistry due to their prevalence in various organic compounds. While conventional protocols have largely relied on transition metal catalysis, recent advancements in organocatalysis, particularly with radical NHC catalysis have sparked interest in the direct functionalization of "inert" C(sp3) -H bonds for cross C-C coupling with carbonyl moieties. This strategy involves selective cleavage of C(sp3) -H bonds to generate key carbon radicals, often achieved via hydrogen atom transfer (HAT) processes. By leveraging the bond dissociation energy (BDE) and polarity effects, HAT enables the rapid functionalization of diverse C(sp3)-H substrates, such as ethers, amines, and alkanes. This mini-review summarizes the progress in carbene organocatalytic functionalization of inert C(sp3)-H bonds enabled by HAT processes, categorizing them into two sections: 1) C-H functionalization involving acyl azolium intermediates; and 2) functionalization of C-H bonds via reductive Breslow intermediates.
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Grants
- U23A20201, 22071036 National Natural Science Foundation of China
- 2022YFD1700300 National Key Research and Development Program of China
- (2022)47) National Natural Science Fund for Excellent Young Scientists Fund Program (Overseas)-YQHW, the starting grant of Guizhou University
- [Qiankehejichu-ZK[2024]yiban030 Science and Technology Department of Guizhou Province
- 111 Program, D20023 Program of Introducing Talents of Discipline to Universities of China (111 Program, D20023) at Guizhou University
- [Qianjiaohe KY (2020)004] Frontiers Science Center for Asymmetric Synthesis and Medicinal Molecules, Department of Education, Guizhou Province
- MOE AcRF Tier 1 Award (RG84/22, RG70/21), MOE AcRF Tier 2 (MOE-T2EP10222-0006), and MOE AcRF Tier 3 Award (MOE2018-T3-1-003) Ministry of Education, Singapore
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Affiliation(s)
- Fengfei Lu
- State Key Laboratory of Green Pesticides, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Fen Su
- State Key Laboratory of Green Pesticides, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Shijie Pan
- State Key Laboratory of Green Pesticides, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Xiuli Wu
- State Key Laboratory of Green Pesticides, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Xingxing Wu
- State Key Laboratory of Green Pesticides, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Yonggui Robin Chi
- State Key Laboratory of Green Pesticides, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, Singapore, 637371, Singapore
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11
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Luo Z, Liao M, Li W, Zhao S, Tang K, Zheng P, Chi YR, Zhang X, Wu X. Ionic Hydrogen Bond-Assisted Catalytic Construction of Nitrogen Stereogenic Center via Formal Desymmetrization of Remote Diols. Angew Chem Int Ed Engl 2024; 63:e202404979. [PMID: 38745374 DOI: 10.1002/anie.202404979] [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: 03/13/2024] [Revised: 04/23/2024] [Accepted: 05/14/2024] [Indexed: 05/16/2024]
Abstract
The control of noncarbon stereogenic centers is of profound importance owing to their enormous interest in bioactive compounds and chiral catalyst or ligand design for enantioselective synthesis. Despite various elegant approaches have been achieved for construction of S-, P-, Si- and B-stereocenters over the past decades, the catalyst-controlled strategies to govern the formation of N-stereogenic compounds have garnered less attention. Here, we disclose the first organocatalytic approach for efficient access to a wide range of nitrogen-stereogenic compounds through a desymmetrization approach. Intriguingly, the pro-chiral remote diols, which are previously not well addressed with enantiocontrol, are well differentiated by potent chiral carbene-bound acyl azolium intermediates. Preliminary studies shed insights on the critical importance of the ionic hydrogen bond (IHB) formed between the dimer aggregate of diols to afford the chiral N-oxide products that feature a tetrahedral nitrogen as the sole stereogenic element with good yields and excellent enantioselectivities. Notably, the chiral N-oxide products could offer an attractive strategy for chiral ligand design and discovery of potential antibacterial agrochemicals.
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Grants
- National Natural Science Fund for Excellent Young Scientists Fund Program (Overseas)-YQHW
- the starting grant of Guizhou University [(2022)47)]
- National Natural Science Foundation of China (21732002, 22061007, 22071036, and 22207022)
- Frontiers Science Center for Asymmetric Synthesis and Medicinal Molecules
- Department of Education, Science and Technology Department of Guizhou Province [Qiankehe-jichu-ZK[2022]zhongdian024]
- Program of Introducing Talents of Discipline to Universities of China (111 Program, D20023) at Guizhou University
- Singapore National Research Foundation under its NRF Investigatorship (NRF-NRFI2016-06) and Competitive Research Program (NRF-CRP22-2019-0002)
- Ministry of Education, Singapore, under its MOE AcRF Tier 1 Award (RG7/20, RG70/21), MOE AcRF Tier 2 (MOE2019-T2-2-117)
- a Chair Professorship Grant, and Nanyang Technological University
- (2022)47 starting grant of Guizhou University
- 21732002 National Natural Science Foundation of China
- 22061007 National Natural Science Foundation of China
- 22071036 National Natural Science Foundation of China
- 22207022 National Natural Science Foundation of China
- Qiankehe-jichu-ZK[2022]zhongdian024 Department of Education, Science and Technology Department of Guizhou Province
- Qiankehejichu-ZK[2024]yiban030 Department of Education, Science and Technology Department of Guizhou Province
- NRF-NRFI2016-06 Singapore National Research Foundation under its NRF Investigatorship and Competitive Research Program
- NRF-CRP22-2019-0002 Singapore National Research Foundation under its NRF Investigatorship and Competitive Research Program
- RG7/20, RG70/21 Ministry of Education, Singapore, under its MOE AcRF Tier 1 Award, MOE AcRF Tier 2
- MOE2019-T2-2-117 Ministry of Education, Singapore, under its MOE AcRF Tier 1 Award, MOE AcRF Tier 2
- Chair Professorship Grant, and Nanyang Technological University
- C210812008 Agency for Science, Technology and Research (A*STAR) under its Career Development Fund
- M22K3c0091 Manufacturing, TradeConnectivity (MTC) Young Individual Research Grants.
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Affiliation(s)
- Zhongfu Luo
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Minghong Liao
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Wei Li
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Sha Zhao
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Kun Tang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Pengcheng Zheng
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
| | - Yonggui Robin Chi
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, Singapore, 637371, Singapore
| | - Xinglong Zhang
- Institute of High Performance Computing (IHPC), A*STAR, Singapore, 138632, Singapore
| | - Xingxing Wu
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang, 550025, China
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12
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Zhang Y, Wang Q, Long Z, Zuo Y, Liu L, Yan L. Synthesis of Quinolinoneylnitrones and Coumarinylnitrones via a Cascade Hydroamination and Aza-MBH-Type Reaction. J Org Chem 2024; 89:10327-10332. [PMID: 38961650 DOI: 10.1021/acs.joc.4c00744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
Nitrones are quite useful intermediates and have been broadly applied in organic synthesis, drug discovery, and photochemistry research. Many functional nitrones have been successfully prepared using various strategies. In this work, an efficient method for synthesizing novel quinolinoneylnitrone and coumarinylnitrone derivatives was developed. Preliminary mechanistic research suggests that this protocol included a cascade hydroamination and aza-MBH-type reaction.
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Affiliation(s)
- Yan Zhang
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China
| | - Qingtao Wang
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China
| | - Zhiwu Long
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China
| | - Yaqing Zuo
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China
| | - Li Liu
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China
| | - Longjia Yan
- School of Pharmaceutical Sciences, Guizhou University, Guiyang 550025, China
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13
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Mroczyńska K, Dobrzańska L, Rafiński Z. Enantioselective synthesis of C3-functionalized 2,1-benzothiazine 2,2-dioxides by N-heterocyclic carbene catalysis. Chem Commun (Camb) 2024; 60:7176-7179. [PMID: 38904356 DOI: 10.1039/d4cc01754d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
We present herein an approach for the enantioselective C3-functionalization of 2,1-benzothiazine 2,2-dioxides using N-heterocyclic carbene (NHC) catalysis. Our method involves a sequence of [3+3] cycloaddition and ring-opening reactions with different N- and O-nucleophiles, followed by silylation. Overcoming the challenge of selectivity targeting the C3 position, this protocol demonstrates a broad substrate scope and high enantioselectivity. This marks a significant advancement in the field of NHC-catalyzed transformations.
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Affiliation(s)
- Karina Mroczyńska
- Nicolaus Copernicus University in Toruń, Faculty of Chemistry, 7 Gagarin Street, 87-100 Toruń, Poland.
| | - Liliana Dobrzańska
- Nicolaus Copernicus University in Toruń, Faculty of Chemistry, 7 Gagarin Street, 87-100 Toruń, Poland.
| | - Zbigniew Rafiński
- Nicolaus Copernicus University in Toruń, Faculty of Chemistry, 7 Gagarin Street, 87-100 Toruń, Poland.
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14
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Liang YJ, Gao YY, Han HB, Li L, Liu L. Enantioselective synthesis of 4-aryl-3,4-dihydrocoumarins via N-heterocyclic carbene catalyzed β-arylation/cyclization of α-bromoenals. Org Biomol Chem 2024; 22:5101-5104. [PMID: 38859801 DOI: 10.1039/d4ob00756e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
4-Aryl-3,4-dihydrocoumarins are one of the most important structural motifs. Herein, we disclose an enantioselective N-heterocyclic carbene catalyzed β-arylation/cyclization of α-bromoenals with 3-aminophenols under mild conditions. The protocol allows for the rapid preparation of 4-aryl-3,4-dihydrocoumarins in acceptable yields with good enantioselectivities. The products of this reaction could be converted into chiral diarylpropanoic acid derivatives without erosion of the enantioselectivity.
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Affiliation(s)
- Yu-Jing Liang
- College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
- Henan Engineering Laboratory of Green Synthesis for Pharmaceuticals, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
| | - Yuan-Yuan Gao
- Henan Engineering Laboratory of Green Synthesis for Pharmaceuticals, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
| | - Hua-Bo Han
- Henan Engineering Laboratory of Green Synthesis for Pharmaceuticals, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
| | - Lu Li
- Henan Engineering Laboratory of Green Synthesis for Pharmaceuticals, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
| | - Lantao Liu
- College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
- Henan Engineering Laboratory of Green Synthesis for Pharmaceuticals, College of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu 476000, China.
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15
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Ewing PMDA, Majhi PK, Prentice C, Young CM, van Rees K, Arnold PL, Zysman-Colman E, Smith AD. α-Phenylthioaldehydes for the effective generation of acyl azolium and azolium enolate intermediates. Chem Sci 2024; 15:9369-9375. [PMID: 38903219 PMCID: PMC11186317 DOI: 10.1039/d3sc06879j] [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: 12/21/2023] [Accepted: 05/09/2024] [Indexed: 06/22/2024] Open
Abstract
α-Phenylthioaldehydes are readily prepared using a simple multi-step procedure and herein are introduced as a new precursor for the NHC-catalysed generation of acyl azolium and azolium enolate intermediates that are of widespread synthetic interest and utility. Treatment of α-phenylthioaldehydes with an NHC precatalyst and base produces an efficient redox rearrangement via a Breslow intermediate, elimination of thiophenolate, and subsequent rebound addition to the generated acyl azolium to give the corresponding thiol ester. In the presence of an external alcohol, competition between redox rearrangement and redox esterification can be controlled through judicious choice of the N-aryl substituent within the NHC precatalyst and the base used in the reaction. With NEt3 as base, NHCs bearing electron-withdrawing (N-C6F5 or N-C6H2Cl3) substituents favour redox rearrangement, while triazolium precatalysts with electron-rich N-aryl substituents (N-Ph, N-Mes) result in preferential redox esterification. Using DBU, redox esterification is preferred due to transesterification of the initially formed thiol ester product. Additionally, α-phenylthioaldehyde-derived azolium enolates have been used in enantioselective formal [4 + 2]-cycloaddition reactions to access dihydropyridinone heterocycles with high enantioselectivity (up to >95 : 5 dr, 98 : 2 er).
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Affiliation(s)
- Paul M D A Ewing
- EaStCHEM, School of Chemistry, University of St Andrews St Andrews, Fife KY16 9ST UK
- EaStCHEM, School of Chemistry, University of Edinburgh EH9 3JF UK
| | - Pankaj Kumar Majhi
- EaStCHEM, School of Chemistry, University of St Andrews St Andrews, Fife KY16 9ST UK
| | - Callum Prentice
- EaStCHEM, School of Chemistry, University of St Andrews St Andrews, Fife KY16 9ST UK
| | - Claire M Young
- EaStCHEM, School of Chemistry, University of St Andrews St Andrews, Fife KY16 9ST UK
| | | | - Polly L Arnold
- Dept of Chemistry, University of California Berkeley CA 94720 USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Eli Zysman-Colman
- EaStCHEM, School of Chemistry, University of St Andrews St Andrews, Fife KY16 9ST UK
| | - Andrew D Smith
- EaStCHEM, School of Chemistry, University of St Andrews St Andrews, Fife KY16 9ST UK
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16
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Pu Y, Wang M, Tian W, Ge X, Zhu D, Wang C, Zeng Y, Tao F, Deng Y, Lu J. N-heterocyclic carbene catalyzed [2 + 3] annulation reaction for the synthesis of trifluoroethyl 3,2'-spirooxindole γ-lactam. RSC Adv 2024; 14:18453-18458. [PMID: 38860250 PMCID: PMC11163332 DOI: 10.1039/d4ra02252a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 05/23/2024] [Indexed: 06/12/2024] Open
Abstract
Asymmetric catalytic processes promoted by N-heterocyclic carbenes (NHCs) hold great potential for the sustainable preparation of chiral molecules. However, catalyzing the reactions by manipulating the reactive intermediates is challenging. We report herein that the known NHC-catalyzed [3 + 2] annulation reaction between ketimine and enal can also be turned into a [2 + 3] annulation reaction for the highly enantioselective direct synthesis of trifluoroethyl 3,2'-spirooxindole γ-lactams (4) through timely catalysis of the intermediates. DFT calculations revealed that this transformation included the key step of the nucleophilic attack of the Breslow intermediate M2 derived from NHC and enal (2) to the unattacked ketimine (1). Our study demonstrates that it is possible to tune the desired selectivities through the dynamic catalysts of the reactive intermediates.
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Affiliation(s)
- Yiru Pu
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
| | - Maolin Wang
- Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College Shantou Guangdong Province 515000 China
| | - Wanrong Tian
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
| | - Xian Ge
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
| | - Dikai Zhu
- Research and Development Centre, China Tobacco Sichuan Industrial Co. Ltd Chengdu 610066 China
| | - Chuanqi Wang
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
| | - Yingjie Zeng
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
| | - Feiyan Tao
- Research and Development Centre, China Tobacco Sichuan Industrial Co. Ltd Chengdu 610066 China
| | - Yun Deng
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
| | - Jun Lu
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
- Institute for Advancing Translational Medicine in Bone & Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University Hong Kong SAR 999077 China
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17
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Jin Z, Yang Y, He Z, Huang Z, Hu Y, Jin H, Zhou B. Nickel-Catalyzed Cross-Coupling Reaction of Aryl Bromides/Nitriles with Imidazolium Salts Involving Inert C-N Bond Cleavage. Org Lett 2024; 26:4520-4525. [PMID: 38752885 DOI: 10.1021/acs.orglett.4c01386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
We herein present a nickel-catalyzed cross-coupling reaction of aryl halides and nitriles with imidazolium salts. A series of 2-arylated imidazoles could be obtained in moderate to good yields through inert C-N bond cleavage. The imidazolium salt in this reaction acts as both a coupling partner and N-heterocyclic carbene (NHC) ligand precursor. Mechanistic studies reveal that consecutive steps of migratory insertion of the NHC into the aryl C-Ni bond and β-C elimination might be involved in the proposed reaction mechanism.
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Affiliation(s)
- Zhou Jin
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Yanhao Yang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Zhichang He
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Zhengzhe Huang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Yuanyuan Hu
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Hongwei Jin
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
- Eco-industrial Innovation Institute, Zhejiang University of Technology, Quzhou, Zhejiang 324400, China
| | - Bingwei Zhou
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
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18
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Liu B, Zhou X, Liu Q, Yang Z, Mao Y, He Q, Zhang T, Kong X, Zhang J, Liao W, Tang L. Carbene-Catalyzed [4+2] Cycloaddition of Cyclobutenones and Isatins for Quick Access to Chiral Chlorine-Containing Spirocyclic δ-Lactones. J Org Chem 2024; 89:7286-7294. [PMID: 38696309 DOI: 10.1021/acs.joc.4c00295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024]
Abstract
Here we report a carbene-catalyzed enantio- and diastereoselective [4+2] cycloaddition reaction of cyclobutenones with isatins for the quick and efficient synthesis of spirocyclic δ-lactones bearing a chiral chlorine. A broad range of substrates with various substitution patterns proceed smoothly in this reaction, with the spirooxindole δ-lactone products afforded in generally good to excellent yields and optical purities under mild reaction conditions.
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Affiliation(s)
- Bin Liu
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Xian Zhou
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Qinqin Liu
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Zaihui Yang
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Yuanhu Mao
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Qing He
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Tianyuan Zhang
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Xiangkai Kong
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Jiquan Zhang
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Weike Liao
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
| | - Lei Tang
- Guizhou Provincial Engineering Technology Research Center for Chemical Drug R&D, School of Pharmacy, Guizhou Medical University, Guiyang 550004, China
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19
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Barańska I, Ośmiałowski B, Rafińska K, Rafiński Z. Construction of Highly Functionalized 2-Styrylfurans by N-Heterocyclic Carbene/Brønsted Acid Catalysis. Org Lett 2024; 26:3514-3518. [PMID: 38651753 PMCID: PMC11077487 DOI: 10.1021/acs.orglett.4c00836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/17/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
This research presents an original method for synthesizing styrylfurans using N-heterocyclic carbenes (NHCs) and Brønsted acid catalysis. By exploiting 2,4-dioxoesters as conjugated 1,3-dicarbonyls, we have developed a technique allowing the efficient formation of highly functionalized styrylfurans with interesting photochemical properties, through a NHC-catalyzed cross-benzoin reaction followed by a Brønsted acid-driven Paal-Knorr-like condensation. This approach permits the integration of various substituents on the furan ring, with preliminary biological studies indicating potential as fluorescent dyes.
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Affiliation(s)
- Izabela Barańska
- Nicolaus Copernicus University
in Torun, Faculty of Chemistry, 7 Gagarin Street, Torun 87-100, Poland
| | - Borys Ośmiałowski
- Nicolaus Copernicus University
in Torun, Faculty of Chemistry, 7 Gagarin Street, Torun 87-100, Poland
| | - Katarzyna Rafińska
- Nicolaus Copernicus University
in Torun, Faculty of Chemistry, 7 Gagarin Street, Torun 87-100, Poland
| | - Zbigniew Rafiński
- Nicolaus Copernicus University
in Torun, Faculty of Chemistry, 7 Gagarin Street, Torun 87-100, Poland
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20
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Bag D, Sawant SD. Diastereoselective synthesis of functionalized spiroindolines via intramolecular ipso-iodocyclization/nucleophile addition cascade reactions of indole-tethered ynones. Org Biomol Chem 2024; 22:3415-3419. [PMID: 38595312 DOI: 10.1039/d4ob00112e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Herein, we describe a highly diastereoselective approach for synthesizing polyfunctionalized spiroindolines from indolyl-ynones involving an ipso-iodocyclization/nucleophile addition cascade. The developed strategy allows the formation of a spirocyclic core and the installation of two functional groups in a single operation. Also this strategy is accompanied by the generation of two C-C and one C-I bonds and two contiguous stereocenters.
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Affiliation(s)
- Debojyoti Bag
- Natural Products and Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu & Kashmir, 180001, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Sanghapal D Sawant
- Natural Products and Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu & Kashmir, 180001, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune-411008, India
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21
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Bacaicoa S, Stenkvist S, Sundén H. Redox Active N-Heterocyclic Carbenes in Oxidative NHC Catalysis. Org Lett 2024; 26:3114-3118. [PMID: 38551486 DOI: 10.1021/acs.orglett.4c00731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
An N-heterocyclic carbene (NHC) covalently linked to a quinone introduces a novel avenue for internal oxidations within oxidative NHC catalysis. The deployment of this hybrid NHC class promotes intramolecular electronic flow in the oxidation of the Breslow intermediate to acyl azolium. The use of the redox active NHC as a catalyst is facilitated by employing aerobic regeneration, yielding carboxylic esters with efficiencies of ≤99%, while generating water as the sole byproduct.
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Affiliation(s)
- Sara Bacaicoa
- University of Gothenburg, Medicinaregatan 19, 413 90 Gothenburg, Sweden
| | - Simon Stenkvist
- University of Gothenburg, Medicinaregatan 19, 413 90 Gothenburg, Sweden
| | - Henrik Sundén
- University of Gothenburg, Medicinaregatan 19, 413 90 Gothenburg, Sweden
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22
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Barik S, Sankar G, Biju AT. Enantioselective synthesis of tricyclic oxoquinolines via NHC-catalyzed Michael-aldol-lactamization-dehydration cascade. Chem Commun (Camb) 2024; 60:4290-4293. [PMID: 38445724 DOI: 10.1039/d4cc00502c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
The enantioselective synthesis of tricyclic oxoquinolines via NHC-catalyzed cascade reaction of enals with malonates bearing a 2-aminophenyl group is reported. The chiral α,β-unsaturated acylazoliums underwent a smooth Michael-aldol-lactamization-dehydration quadruple cascade with the amino malonate derivative to afford the desired tricyclic products.
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Affiliation(s)
- Shilpa Barik
- Department of Organic Chemistry, Indian Institute of Science, Bangalore-560012, India.
| | - Ganga Sankar
- Department of Organic Chemistry, Indian Institute of Science, Bangalore-560012, India.
| | - Akkattu T Biju
- Department of Organic Chemistry, Indian Institute of Science, Bangalore-560012, India.
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23
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Barańska I, Dobrzańska L, Rafiński Z. Enantioselective [3 + 3] Annulation-Deoxalation Strategy for Rapid Access to δ-Oxoesters via N-Heterocyclic Carbene Catalysis. Org Lett 2024; 26:1207-1211. [PMID: 38325001 PMCID: PMC10877609 DOI: 10.1021/acs.orglett.3c04397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 01/31/2024] [Accepted: 02/06/2024] [Indexed: 02/09/2024]
Abstract
A new and unprecedented stereoselective synthetic approach to δ-oxoesters derivatives from readily available starting materials has been developed. This method, catalyzed by N-heterocyclic carbene, involves an annulation-deoxalation reaction of alkynyl aldehydes with 2,4-diketoesters and proceeds via the chiral α,β-unsaturated acylazolium intermediates. The annulation includes the in situ formation of dihydropyranones, which undergo ring-opening methanolysis with Lewis acid activation, followed by deoxalation to afford chiral 1,5-ketoesters in moderate to good yields.
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Affiliation(s)
- Izabela Barańska
- Faculty of Chemistry, Nicolaus Copernicus University in Torun, 7 Gagarin Street, 87-100 Torun, Poland
| | - Liliana Dobrzańska
- Faculty of Chemistry, Nicolaus Copernicus University in Torun, 7 Gagarin Street, 87-100 Torun, Poland
| | - Zbigniew Rafiński
- Faculty of Chemistry, Nicolaus Copernicus University in Torun, 7 Gagarin Street, 87-100 Torun, Poland
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24
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An H, Liu S, Wang SJ, Yu X, Shi C, Lin H, Poh SB, Yang H, Wong MW, Zhao Y, Tu Z, Lu S. Kinetic Resolution of Acyclic Tertiary Propargylic Alcohols by NHC-Catalyzed Enantioselective Acylation. Org Lett 2024; 26:702-707. [PMID: 38206074 DOI: 10.1021/acs.orglett.3c04134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
We report herein an efficient NHC-catalyzed kinetic resolution of acyclic tertiary propargylic alcohols that provides them in high to excellent enantioselectivity. This is the first example of kinetic resolution realized by enantioselective acylation. The recovered enantioenriched alcohols can be facilely converted into other valuable compounds such as densely functionalized tertiary alcohols and carbmates in high yields and excellent stereopurity. Density functional theory calculations were performed to determine the reaction mechanism and to understand the origin of enantiodiscrimination.
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Affiliation(s)
- Hao An
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), and Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Shifei Liu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), and Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Shao-Jie Wang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), and Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Xiaoyi Yu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), and Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Chenqi Shi
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Haonan Lin
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Si Bei Poh
- Department of Chemistry, National University of Singapore, 3 Science Drive, Republic of Singapore 117543
| | - Hui Yang
- Department of Chemistry, National University of Singapore, 3 Science Drive, Republic of Singapore 117543
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive, Republic of Singapore 117543
| | - Yu Zhao
- Department of Chemistry, National University of Singapore, 3 Science Drive, Republic of Singapore 117543
| | - Zhifeng Tu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), and Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
| | - Shenci Lu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE), and Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China
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25
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Mondal BD, Gorai S, Nath R, Paul A, Guin J. Enantioselective Amination of 3-Substituted-2-benzofuranones via Non-covalent N-Heterocyclic Carbene Catalysis. Chemistry 2024; 30:e202303115. [PMID: 37997460 DOI: 10.1002/chem.202303115] [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: 09/25/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 11/25/2023]
Abstract
Herein, an efficient method for asymmetric α-amination of 2-benzofuranones with N-heterocyclic carbene (NHC) catalysis is reported. The process is based on non-covalent interaction of NHC with substrate, facilitating the formation of a chiral ion-pair that encompasses enolate and azolium salt. The activated enolate adds to an electrophilic amine source with sufficient facial control to furnish an enantioenriched product having an amine substituted quaternary stereocenter. The process displays a broad substrate scope. A preparative scale synthesis has been achieved. Preliminary mechanistic investigations based on experimental and DFT studies suggest a reaction pathway that involves non-covalent substrate/NHC interactions and essentially implicate the role of π-π interaction in diastereomeric transition states for stereo-chemical discrimination.
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Affiliation(s)
- Bhaskar Deb Mondal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2 A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India
| | - Sadhan Gorai
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2 A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India
| | - Rounak Nath
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2 A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India
| | - Ankan Paul
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2 A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India
| | - Joyram Guin
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2 A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India
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26
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Zhou BA, Li XN, Zhang CL, Wang ZX, Ye S. Enantioselective Synthesis of Axially Chiral Diaryl Ethers via NHC Catalyzed Desymmetrization and Following Resolution. Angew Chem Int Ed Engl 2024; 63:e202314228. [PMID: 38019184 DOI: 10.1002/anie.202314228] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 11/30/2023]
Abstract
Axially chiral diaryl ethers are present in numerous natural products and bioactive molecules. However, only few catalytic enantioselective approaches have been established to access diaryl ether atropisomers. Herein, we report the N-heterocyclic carbene-catalyzed enantioselective synthesis of axially chiral diaryl ethers via desymmetrization of prochiral 2-aryloxyisophthalaldehydes with aliphatic alcohols, phenol derivatives, and heteroaromatic amines. This reaction features mild reaction conditions, good functional group tolerance, broad substrate scope and excellent enantioselectivity. The utility of this methodology is illustrated by late-stage functionalization, gram-scale synthesis, and diverse enantioretentive transformations. Control experiments and DFT calculations support the association of NHC-catalyzed desymmetrization with following kinetic resolution to enhance the enantioselectivity.
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Affiliation(s)
- Bang-An Zhou
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Xue-Ning Li
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Chun-Lin Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China
| | - Zhi-Xiang Wang
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Song Ye
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
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27
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Wang SJ, Wang X, Xin X, Zhang S, Yang H, Wong MW, Lu S. Organocatalytic diastereo- and atroposelective construction of N-N axially chiral pyrroles and indoles. Nat Commun 2024; 15:518. [PMID: 38225235 PMCID: PMC10789812 DOI: 10.1038/s41467-024-44743-z] [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: 02/11/2023] [Accepted: 12/28/2023] [Indexed: 01/17/2024] Open
Abstract
The construction of N-N axially chiral motifs is an important research topic, owing to their wide occurrence in natural products, pharmaceuticals and chiral ligands. One efficient method is the atroposelective dihydropyrimidin-4-one formation. We present herein a direct catalytic synthesis of N-N atropisomers with simultaneous creation of contiguous axial and central chirality by oxidative NHC (N-heterocyclic carbenes) catalyzed (3 + 3) cycloaddition. Using our method, we are able to synthesize structurally diverse N-N axially chiral pyrroles and indoles with vicinal central chirality or bearing a 2,3-dihydropyrimidin-4-one moiety in moderate to good yields and excellent enantioselectivities. Further synthetic transformations of the obtained axially chiral pyrroles and indoles derivative products are demonstrated. The reaction mechanism and the origin of enantioselectivity are understood through DFT calculations.
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Affiliation(s)
- Shao-Jie Wang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, China
| | - Xia Wang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, China
| | - Xiaolan Xin
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, China
| | - Shulei Zhang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, China
| | - Hui Yang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore.
| | - Shenci Lu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, China.
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28
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Rizzo C, Pace A, Pibiri I, Buscemi S, Palumbo Piccionello A. From Conventional to Sustainable Catalytic Approaches for Heterocycles Synthesis. CHEMSUSCHEM 2023:e202301604. [PMID: 38140917 DOI: 10.1002/cssc.202301604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 12/24/2023]
Abstract
Synthesis of heterocyclic compounds is fundamental for all the research area in chemistry, from drug synthesis to material science. In this framework, catalysed synthetic methods are of great interest to effective reach such important building blocks. In this review, we will report on some selected examples from the last five years, of the major improvement in the field, focusing on the most important conventional catalytic systems, such as transition metals, organocatalysts, to more sustainable ones such as photocatalysts, iodine-catalysed reaction, electrochemical reactions and green innovative methods.
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Affiliation(s)
- Carla Rizzo
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, Italy, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo
| | - Andrea Pace
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, Italy, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo
| | - Ivana Pibiri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, Italy, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo
| | - Silvestre Buscemi
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, Italy, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo
| | - Antonio Palumbo Piccionello
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, Italy, University of Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo
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29
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Shee S, Shree Ranganathappa S, Gadhave MS, Gogoi R, Biju AT. Enantioselective Synthesis of C-O Axially Chiral Diaryl Ethers by NHC-Catalyzed Atroposelective Desymmetrization. Angew Chem Int Ed Engl 2023; 62:e202311709. [PMID: 37986240 DOI: 10.1002/anie.202311709] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 11/15/2023] [Accepted: 11/17/2023] [Indexed: 11/22/2023]
Abstract
Axially chiral diaryl ethers, a distinguished class of atropisomers possessing unique dual C-O axis, hold immense potential for diverse research domains. In contrast to the catalytic enantioselective synthesis of conventional single axis bearing atropisomers, the atroposelective synthesis of axially chiral ethers containing flexible C-O axis remains a significant challenge. Herein, we demonstrate the first N-heterocyclic carbene (NHC)-catalyzed synthesis of axially chiral diaryl ethers via atroposelective esterification of dialdehyde-containing diaryl ethers. Mechanistically, the reaction proceeds via NHC-catalyzed desymmetrization strategy to afford the corresponding axially chiral diaryl ether atropisomers in good yields and high enantioselectivities under mild conditions. The derivatization of the synthesized product expands the utility of present strategy via access to a library of C-O axially chiral compounds. The temperature dependency and preliminary investigations on the racemization barrier of C-O bonds are also presented.
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Affiliation(s)
- Sayan Shee
- Department of Organic Chemistry, Indian Institute of Science, 560012, Bangalore, India
| | | | - Mahesh S Gadhave
- Department of Organic Chemistry, Indian Institute of Science, 560012, Bangalore, India
| | - Romin Gogoi
- Department of Organic Chemistry, Indian Institute of Science, 560012, Bangalore, India
| | - Akkattu T Biju
- Department of Organic Chemistry, Indian Institute of Science, 560012, Bangalore, India
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30
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Li J, Duan XY, Ren X, Li Y, Qi J. N-Heterocyclic Carbene-Catalyzed [3 + 3] Annulation of 5-Aminopyrazoles with Enals: Enantioselective Synthesis of Pyrazolo[3,4- b]pyridones. J Org Chem 2023; 88:16621-16632. [PMID: 37967027 DOI: 10.1021/acs.joc.3c00793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
An enantioselective construction of pyrazolo[3,4-b]pyridones was achieved via N-heterocyclic carbene-catalyzed [3 + 3] annulation of enals with 5-aminopyrazoles. This protocol not only offers a highly efficient synthetic approach for the preparation of various substituted pyrazolo[3,4-b]pyridones but also provides an effective method for the rapid synthesis of enantiopure spirooxindone derivatives.
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Affiliation(s)
- Jiahan Li
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China
| | - Xiao-Yong Duan
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China
- State Key Laboratory of New Pharmaceutical Preparations and Excipients, College of Chemistry and Materials Science, Hebei University, Baoding 071002, China
| | - Xiaojie Ren
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China
| | - Yanting Li
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China
| | - Jing Qi
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China
- State Key Laboratory of New Pharmaceutical Preparations and Excipients, College of Chemistry and Materials Science, Hebei University, Baoding 071002, China
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31
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Wang X, Wu S, Yang R, Song H, Liu Y, Wang Q. Recent advances in combining photo- and N-heterocyclic carbene catalysis. Chem Sci 2023; 14:13367-13383. [PMID: 38033906 PMCID: PMC10685334 DOI: 10.1039/d3sc03274d] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 10/27/2023] [Indexed: 12/02/2023] Open
Abstract
N-Heterocyclic carbenes (NHCs) are unique Lewis basic catalysts that mediate various organic transformations by means of polarity reversal. Although the scope of research on two-electron reactions mediated by NHC catalysts has been expanding, the types of these reactions are limited by the inability of NHCs to engage sp3-electrophiles. However, the revival of photocatalysis has accelerated the development of free-radical chemistry, and combining photoredox catalysis and NHC catalysis to achieve NHC-mediated radical reactions under mild conditions could overcome the above-mentioned limitation. This review summarizes recent advances in combining photoredox and NHC catalysis, focusing on elucidation and exploration of mechanisms, with the aim of identifying challenges and opportunities to develop more types of catalytic models.
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Affiliation(s)
- Xiaochen Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University Tianjin 300071 People's Republic of China
| | - Senhui Wu
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University Tianjin 300071 People's Republic of China
| | - Rongxin Yang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University Tianjin 300071 People's Republic of China
| | - Hongjian Song
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University Tianjin 300071 People's Republic of China
| | - Yuxiu Liu
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University Tianjin 300071 People's Republic of China
| | - Qingmin Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University Tianjin 300071 People's Republic of China
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32
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Mondal B, Chen H, Maiti R, Wang H, Cai H, Mou C, Hao L, Chai H, Chi YR. Carbene-Catalyzed Direct O-Functionalization of Ketone: Atroposelective Access to Non- C2-Symmetric Binaphthyls. Org Lett 2023; 25:8252-8257. [PMID: 37955414 DOI: 10.1021/acs.orglett.3c03141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
Disclosed here is NHC-catalyzed direct intermolecular trapping of the ketone oxygen atom with the acyl azolium intermediate. The overall reaction is a dynamic kinetic resolution process that converts ketone to the corresponding enol ester with well-controlled axial chirality. Our reaction eventually affords non-C2-symmetric binaphthyl derivatives with important applications, such as in the area of asymmetric catalysis.
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Affiliation(s)
- Bivas Mondal
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Hang Chen
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Rakesh Maiti
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Hongling Wang
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Hui Cai
- National Key Laboratory of Green Pesticide, Guizhou University, Guiyang, Guizhou 550025, People's Republic of China
| | - Chengli Mou
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550025, People's Republic of China
| | - Lin Hao
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Huifang Chai
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550025, People's Republic of China
| | - Yonggui Robin Chi
- National Key Laboratory of Green Pesticide, Guizhou University, Guiyang, Guizhou 550025, People's Republic of China
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
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33
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Biesen L, Müller TJJ. Aroyl-S,N-Ketene Acetals: Luminous Renaissance of a Class of Heterocyclic Compounds. Chemistry 2023; 29:e202302067. [PMID: 37638792 DOI: 10.1002/chem.202302067] [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: 06/29/2023] [Revised: 08/25/2023] [Accepted: 08/28/2023] [Indexed: 08/29/2023]
Abstract
Aroyl-S,N-ketene acetals represent a peculiar class of heterocyclic merocyanines, compounds bearing pronounced and rather short dipoles with great push-pull characteristics that define their rich properties. They are accessible via a wide array of synthetic concepts and procedures, ranging from addition-elimination and condensation procedures up to rearrangement and metal-mediated reactions. With our work from 2020, aroyl-S,N-ketene acetals have been identified as powerful and promising dyes with pronounced and vastly tunable solid-state emission and aggregation-induced emission properties. One characteristic trademark of this class of dye molecules is the level of control that could be exerted, and which was thoroughly explored. Based on these results, the field was opened to extend the system to bi- and multichromophoric systems by the full toolkit of synthetic organic chemistry thus giving access to even more exciting properties and manifolded substance libraries capitalizing on the AIE properties. This review aims at outlining the reaction-based principles that allow for a swift and facile access to aroyl-S,N-ketene acetals, their methodical and structural evolution and the plethora of fluorescence and aggregation properties.
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Affiliation(s)
- Lukas Biesen
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Thomas J J Müller
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
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34
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Ren X, Duan XY, Li Y, Li J, Qi J. Highly Enantioselective Construction of the Polycyclic Piperazin-2-ones via NHC-Catalyzed [12 + 2] Cycloadditions. Org Lett 2023; 25:7917-7922. [PMID: 37874751 DOI: 10.1021/acs.orglett.3c03171] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
NHC-catalyzed diastereoselective and enantioselective [12 + 2] higher-order cycloadditions of 5H-benzo[a]-pyrrolizine-3-carbaldehydes with cyclic sulfonic imines are described. Various optically pure polycyclic piperazin-2-ones were successfully constructed under mild reaction conditions with excellent diastereoselectivities and enantioselectivities. The generated chiral polycyclic piperazin-2-ones could be transformed to planar-chiral nine-membered cyclic amides via squaramide-catalyzed asymmetric ring-expansion reactions.
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Affiliation(s)
- Xiaojie Ren
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China, and
| | - Xiao-Yong Duan
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China, and
- State Key Laboratory of New Pharmaceutical Preparations and Excipients, College of Chemistry and Materials Science, Hebei University, Baoding 071002, China
| | - Yanting Li
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China, and
| | - Jiahan Li
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China, and
| | - Jing Qi
- College of Chemistry and Materials Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, China, and
- State Key Laboratory of New Pharmaceutical Preparations and Excipients, College of Chemistry and Materials Science, Hebei University, Baoding 071002, China
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35
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Liu C, Wang J, Liu X, Feng J, Du D. NHC-catalyzed radical acylation of cycloalkyl silyl peroxides to access 1,6-,1,7-, and 1,8-diketones. Chem Commun (Camb) 2023; 59:13175-13178. [PMID: 37850247 DOI: 10.1039/d3cc04765b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
An unprecedented N-heterocyclic carbene (NHC)-catalyzed radical acylation of cycloalkyl silyl peroxides was developed using readily available aldehydes as the acylating agents. This protocol provides an exceptionally useful method for the efficient and rapid synthesis of long-chain 1,6-/1,7-/1,8-diketones, especially unsymmetrical ones. This strategy also has the advantages of mild conditions, good functional group compatibility, and potential applications in the late-stage functionalization of aldehydes with bioactive fragments and in the construction of long-chain complex bioactive molecules.
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Affiliation(s)
- Chaolei Liu
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing 210009, P. R. China.
| | - Jingyi Wang
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing 210009, P. R. China.
| | - Xinlong Liu
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing 210009, P. R. China.
| | - Jie Feng
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing 210009, P. R. China.
| | - Ding Du
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing 210009, P. R. China.
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36
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Nong Y, Pang C, Teng K, Zhang S, Liu Q. NHC-Catalyzed Chemoselective Reactions of Enals and Cyclopropylcarbaldehydes for Access to Chiral Dihydropyranone Derivatives. J Org Chem 2023; 88:13535-13543. [PMID: 37682310 DOI: 10.1021/acs.joc.3c01171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/09/2023]
Abstract
An N-heterocyclic carbene (NHC)-catalyzed chemoselective activation reaction of 1-cyclopropylcarbaldehydes and α-alkynyl enals is reported. NHC selectively catalyzes 1-cyclopropylaldehydes, followed by a [2 + 4] cycloaddition reaction with α-alkynyl enals. The target dihydropyranone derivatives bearing different substituents and substitution patterns can be obtained in good to excellent yields with excellent enantio- and diastereoselectivities under mild conditions.
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Affiliation(s)
- Yingling Nong
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, China
| | - Chen Pang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, China
| | - Kunpeng Teng
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, China
| | - Sheng Zhang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, China
| | - Qian Liu
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, China
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37
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Il'in MV, Polonnikov DA, Novikov AS, Sysoeva AA, Safinskaya YV, Bolotin DS. Influence of Coordination to Silver(I) Centers on the Activity of Heterocyclic Iodonium Salts Serving as Halogen-Bond-Donating Catalysts. Chempluschem 2023; 88:e202300304. [PMID: 37675949 DOI: 10.1002/cplu.202300304] [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] [Received: 06/23/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 09/08/2023]
Abstract
Kinetic data based on 1 H NMR monitoring and computational studies indicate that in solution, pyrazole-containing iodonium triflates and silver(I) triflate bind to each other, and such an interplay results in the decrease of the total catalytic activity of the mixture of these Lewis acids compared to the separate catalysis of the Schiff condensation, the imine-isocyanide coupling, or the nucleophilic attack on a triple carbon-carbon bond. Moreover, the kinetic data indicate that such a cooperation with the silver(I) triflate results in prevention of decomposition of the iodonium salts during the reaction progress. XRD study confirms that the pyrazole-containing iodonium triflate coordinates to the silver(I) center via the pyrazole N atom to produce a rare example of a pentacoordinated trigonal bipyramidal dinuclear silver(I) complex featuring cationic ligands.
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Affiliation(s)
- Mikhail V Il'in
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg, 199034, Russia
| | - Denis A Polonnikov
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg, 199034, Russia
| | - Alexander S Novikov
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg, 199034, Russia
- Research Institute of Chemistry, Рeoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya St. 6, Moscow, 117198, Russia
| | - Alexandra A Sysoeva
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg, 199034, Russia
| | - Yana V Safinskaya
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg, 199034, Russia
| | - Dmitrii S Bolotin
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, Saint Petersburg, 199034, Russia
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38
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Li Y, Zhang M, Zhang Z. Mechanisms and Stereoselectivities in the NHC-Catalyzed [4 + 2] Annulation of 2-Bromoenal and 6-Methyluracil-5-carbaldehyde. J Org Chem 2023; 88:12997-13008. [PMID: 37642149 DOI: 10.1021/acs.joc.3c01015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
To disclose the reaction mechanism and selectivity in the NHC-catalyzed reaction of 2-bromoenal and 6-methyluracil-5-carbaldehyde, a systematic computational study has been performed. According to DFT computations, the catalytic cycle is divided into eight elementary steps: nucleophilic attack of the NHC on 2-bromoenal, 1,2-proton transfer, C-Br bond dissociation, 1,3-proton transfer, addition to 6-methyluracil-5-carbaldehyde, [2 + 2] cycloaddition, NHC dissociation, and decarboxylation. The Bronsted acid DABCO·H+ plays a crucial role in proton transfer and decarboxylation steps. The addition to 6-methyluracil-5-carbaldehyde determines both chemoselectivity and stereoselectivity, leading to R-configured carbocycle-fused uracil, in agreement with experimental results. NCI analysis indicates that the CH···N, CH···π, and LP···π interactions should be the key factor for determining the stereoselectivity. ELF analysis shows the main role of the NHC in promoting C-Br bond dissociation. The mechanistic insights obtained in the present work may guide the rational design of potential NHC catalysts.
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Affiliation(s)
- Yan Li
- School of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, P. R. China
| | - Mingchao Zhang
- School of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, P. R. China
| | - Zhiqiang Zhang
- School of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, P. R. China
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39
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Wu Q, Han J, Huang J, Zhang H, Ren M, Zhang X, Fu Z. Asymmetric synthesis of chiral pyrazolo[3,4- b]pyridin-6-ones under carbene catalysis. Org Biomol Chem 2023; 21:6898-6902. [PMID: 37581413 DOI: 10.1039/d3ob01057k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
A structurally diverse set of chiral pyrazolo[3,4-b]pyridin-6-ones was efficiently prepared in excellent yields with excellent enantioselectivities via N-heterocyclic carbene-catalyzed oxidative [3 + 3] annulation of enals with pyrazol-5-amines. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.
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Affiliation(s)
- Qianqian Wu
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
| | - Jinna Han
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
| | - Jie Huang
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
| | - Hailong Zhang
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
| | - Min Ren
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
| | - Xiaoxiang Zhang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Zhenqian Fu
- Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
- Ningbo Institute, Chongqing Technology Innovation Center, Frontiers Science Center for Flexible Electronics (FSCFE), Northwestern Polytechnical University, Xi'an 710072, China
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40
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Zhou N, Zhao F, Wang L, Gao X, Zhao X, Zhang M. NHC-Catalyzed Regioselective Intramolecular Radical Cyclization Reaction for the Synthesis of Benzazepine Derivatives. Org Lett 2023; 25:6072-6076. [PMID: 37550857 DOI: 10.1021/acs.orglett.3c02323] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
A novel and efficient strategy for the synthesis of a series of structurally interesting benzazepine derivatives via an N-heterocyclic carbene-catalyzed regioselective intramolecular radical cyclization has been developed. This protocol features good regioselectivity, good functional-group compatibility, and wide substrate scope, providing a transition-metal- and oxidant-free pathway to access the seven-membered rings under mild reaction conditions. Additionally, further transformation of benzazepines and a large-scale experiment were also conducted.
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Affiliation(s)
- Nengneng Zhou
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Fangli Zhao
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Lei Wang
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Xiang Gao
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Xiaowei Zhao
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Man Zhang
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
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41
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Li Y, Duan XY, Yang C, Wei Y, Li J, Ren X, Qi J. Atroposelective Access to Dihydropyridinones with C-N Axial and Point Chirality via NHC-Catalyzed [3 + 3] Annulation. J Org Chem 2023. [PMID: 37449806 DOI: 10.1021/acs.joc.3c00854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
An N-heterocyclic carbene-catalyzed atroposelective [3 + 3] annulation of enals with 2-aminomaleate derivatives is described. A series of substituted dihydropyridones bearing both C-N axis and point chirality were synthesized with good diastereo- and enantioselectivity under mild conditions. This efficient strategy successfully superpositions an extra point chiral element with an axial backbone, and the generated structurally interesting atropisomers may have potential application in drug discovery.
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42
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Wang HY, Wang XH, Zhou BA, Zhang CL, Ye S. Ketones from aldehydes via alkyl C(sp 3)-H functionalization under photoredox cooperative NHC/palladium catalysis. Nat Commun 2023; 14:4044. [PMID: 37422483 DOI: 10.1038/s41467-023-39707-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/22/2023] [Indexed: 07/10/2023] Open
Abstract
Direct synthesis of ketones from aldehydes features high atom- and step-economy. Yet, the coupling of aldehydes with unactivated alkyl C(sp3)-H remains challenging. Herein, we develop the synthesis of ketones from aldehydes via alkyl C(sp3)-H functionalization under photoredox cooperative NHC/Pd catalysis. The two-component reaction of iodomethylsilyl alkyl ether with aldehydes gave a variety of β-, γ- and δ-silyloxylketones via 1,n-HAT (n = 5, 6, 7) of silylmethyl radicals to generate secondary or tertiary alkyl radicals and following coupling with ketyl radicals from aldehydes under photoredox NHC catalysis. The three-component reaction with the addition of styrenes gave the corresponding ε-hydroxylketones via the generation of benzylic radicals by the addition of alkyl radicals to styrenes and following coupling with ketyl radicals. This work demonstrates the generation of ketyl radical and alkyl radical under the photoredox cooperative NHC/Pd catalysis, and provides two and three component reactions for the synthesis of ketones from aldehydes with alkyl C(sp3)-H functionalization. The synthetic potential of this protocol was also further illustrated by the late-stage functionalization of natural products.
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Affiliation(s)
- Hai-Ying Wang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Xin-Han Wang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Bang-An Zhou
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Chun-Lin Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China.
| | - Song Ye
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China.
- University of Chinese Academy of Sciences, 100049, Beijing, China.
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43
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Gil-Ordóñez M, Maestro A, Andrés JM. Access to Spiropyrazolone-butenolides through NHC-Catalyzed [3 + 2]-Asymmetric Annulation of 3-Bromoenals and 1 H-Pyrazol-4,5-diones. J Org Chem 2023. [PMID: 37167601 DOI: 10.1021/acs.joc.3c00188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The stereoselective synthesis of spirocyclic pyrazolin-5-ones by N-heterocyclic carbene (NHC) organocatalysis has been less studied so far. For this reason and considering the interest of this class of compounds, here, we present the NHC-catalyzed [3 + 2]-asymmetric annulation of β-bromoenals and 1H-pyrazol-4,5-diones that achieves to produce chiral spiropyrazolone-butenolides. The synthesis is general for aryl and heteroaryl β-bromo-α,β-unsaturated aldehydes and 1,3-disubstituted pyrazolones. The spirobutenolides have been obtained in good yields (up to 88%) and enantioselectivities (up to 97:3 er). This constitutes the first described example using pyrazoldiones as the starting materials for this class of spiro compounds.
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Affiliation(s)
- Marta Gil-Ordóñez
- GIR-SintACat-Instituto Universitario CINQUIMA y Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Paseo Belén 7, 47011 Valladolid, Spain
| | - Alicia Maestro
- GIR-SintACat-Instituto Universitario CINQUIMA y Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Paseo Belén 7, 47011 Valladolid, Spain
| | - José M Andrés
- GIR-SintACat-Instituto Universitario CINQUIMA y Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Paseo Belén 7, 47011 Valladolid, Spain
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44
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Morales-Manrique C, Baquero EA, Guevara-Pulido J. Recent Advances in the Synthesis of 3,4-Dihydropyran-2-Ones Organocatalyzed by N-Heterocyclic Carbenes. Molecules 2023; 28:molecules28093743. [PMID: 37175154 PMCID: PMC10179788 DOI: 10.3390/molecules28093743] [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: 03/23/2023] [Revised: 04/21/2023] [Accepted: 04/23/2023] [Indexed: 05/15/2023] Open
Abstract
In recent years, N-heterocyclic carbenes (NHC) have gained recognition as versatile molecules capable of acting as organocatalysts in various reactions, particularly through the activation of aldehydes via Breslow-type adducts. This organocatalytic activation has enabled the production of numerous 3,4-dihydropyran-2-ones and related derivatives. In this review, we provide an overview of the production of 3,4-dihydropyran-2-ones and derivatives via organocatalytic processes involving NHCs over the past eight years. These processes involve the use of a diverse range of substrates, catalysts, and reaction conditions, which can be classified into [4+2]-and [3+3]-type cycloadditions, primarily aimed at synthesizing this skeleton due to its biological activity and multiple stereocenters. These processes are scaled up to the gram scale, and the resulting products are often directed towards epimerization and functionalization to produce more complex molecules with potential applications in the biological field. Finally, we provide a perspective and the future directions of this topic in organic synthesis.
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Affiliation(s)
- Camilo Morales-Manrique
- Estado Sólido y Catálisis Ambiental (ESCA), Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia, Carrera 30 No. 45-03, Bogotá 111321, Colombia
- INQA, Química Farmacéutica, Facultad de Ciencias, Universidad El Bosque, Bogotá 11001, Colombia
| | - Edwin A Baquero
- Estado Sólido y Catálisis Ambiental (ESCA), Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia, Carrera 30 No. 45-03, Bogotá 111321, Colombia
| | - James Guevara-Pulido
- INQA, Química Farmacéutica, Facultad de Ciencias, Universidad El Bosque, Bogotá 11001, Colombia
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45
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Nakano Y, Maddigan-Wyatt JT, Lupton DW. Enantioselective Catalysis by the Umpolung of Conjugate Acceptors Involving N-Heterocyclic Carbene or Organophosphine 1,4-Addition. Acc Chem Res 2023; 56:1190-1203. [PMID: 37093247 DOI: 10.1021/acs.accounts.3c00063] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
ConspectusConjugate acceptors are one of the most common electrophilic functional groups in organic synthesis. While useful in a diverse range of transformations, their applications are largely dominated by the reactions from which their name is derived (i.e., as an acceptor of nucleophiles in the conjugate position). In 2014, we commenced studies focused on their ability to undergo polarity inversion through the conjugate addition of Lewis base catalysts. The first step in this process provides an enolate, from which the well-developed Rauhut-Currier (RC) and Morita-Baylis-Hillman (MBH) reactions can occur; however, tautomerization to provide a species in which the β-carbon of the conjugate acceptor can now act as a donor is also possible. When we commenced studies on this topic, reaction designs with this type of species, particularly when accessed using N-heterocyclic carbenes (NHCs), had been reported on only a handful of occasions. Despite a lack of development, conceptually it was felt that reactions taking advantage of polarity switching by Lewis base conjugate addition have a number of desirable features. Perhaps the most significant is the potential to reimagine a ubiquitous functional group as an entirely new synthon, namely, a donor to electrophiles from the conjugate position.Our work has focused on catalysis with both simple conjugate acceptors and also those embedded within more complicated substrates; the latter has allowed a series of cycloisomerizations and annulation reactions to be achieved. In most cases, the reactions have been possible using enantioenriched chiral NHCs or organophosphines as the Lewis base catalysts thereby delivering enantioselective approaches to novel cyclic molecules. While related chemistry can be accessed with either family of catalyst, in all cases reactions have been designed to take advantage of one or the other. In addition, a fine balance exists between reactions that exploit the initially formed enolate and those that involve the polarity-inverted β-anion. In our studies, this balance is addressed through substrate design, although catalyst control may also be possible. We consider the chemistry discussed in this Account to be in its infancy. Significant challenges remain to be addressed before our broad aim of discovering a universal approach to the polarity inversion of all conjugate acceptors can be achieved. These challenges broadly relate to chemoselectivity with substrates bearing multiple electrophilic functionalities, reliance upon the use of conjugate acceptors, and catalyst efficiency. To address these challenges, advances in catalyst design and catalyst cooperativity are likely required.
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Affiliation(s)
- Yuji Nakano
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | | | - David W Lupton
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
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46
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Gao J, Zhang S, Du D. Alkynyl Acylazolium: a Versatile 1,3-Bielectrophilic 3C-Synthon in NHC-Organocatalysis. CHEM REC 2023:e202300046. [PMID: 36942970 DOI: 10.1002/tcr.202300046] [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: 02/02/2023] [Revised: 03/03/2023] [Indexed: 03/23/2023]
Abstract
N-Heterocyclic carbene (NHC) organocatalysis has emerged as a powerful tool in the field of modern organic synthesis especially in the asymmetric construction of various cyclic skeletons. As an emerging NHC-bound 1,3-bielectrophilic intermediate, alkynyl acylazolium has drawn substantial attention in recent years, and has been used as a versatile 3C-synthon in synthesizing valuable organic molecules since its discovery. In this review, focused on the different pathways for the formation of alkynyl acylazoliums from different precursors like alkynoic esters, alkynoic acids and ynals, the recent advances in the transformations and applications of alkynyl acylazoliums pioneered or developed over the last decade under NHC-catalysis were summarized comprehensively. At the same time, the outlook for further investigation and exploration of novel reaction modes for alkynyl acylazoliums in the future was also discussed.
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Affiliation(s)
- Jian Gao
- Department of Chemistry, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, P. R. China
| | - Simiao Zhang
- Department of Chemistry, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, P. R. China
| | - Ding Du
- Department of Chemistry, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, P. R. China
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47
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Song Y, Wu C, Zhang J, Zhang W, Qin X, Yang Y, Kang G, Jiang J, Liu H. Switchable multipath cascade cyclization to synthesize bicyclic lactams and succinimides via chemodivergent reaction. Chem Commun (Camb) 2023; 59:3313-3316. [PMID: 36852458 DOI: 10.1039/d2cc06841a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Herein, a novel switchable multipath cascade cyclization via chemodivergent reaction between readily available ketoamides and deconjugated butenolides was developed to efficiently synthesize γ-lactone fused γ-lactams and succinimide fused hemiketals. The Aldol/aza-Michael reaction and Aldol/imidation/hemiketalization reaction were enabled by catalytic amounts of two bases, namely tetramethyl guanidine and NaOAc. A wide range of substrate scope with diverse functional group compatibility was demonstrated to deliver the corresponding products with good yield and excellent diastereoselectivity (>60 examples).
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Affiliation(s)
- Yimei Song
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Chaofei Wu
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Jinhai Zhang
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Wenhai Zhang
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Xin Qin
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Yixiao Yang
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Guowei Kang
- Department of Chemistry, The Scripps Research Institute, North Torrey Pines Road, La Jolla 10550, USA.
| | - Jun Jiang
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China.
| | - Hongxin Liu
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, China. .,Institute of New Materials & Industrial Technology, Wenzhou University, Wenzhou, 325035, China.
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48
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Zhang SC, Liu S, Wang X, Wang SJ, Yang H, Li L, Yang B, Wong MW, Zhao Y, Lu S. Enantioselective Access to Triaryl-2-pyrones with Monoaxial or Contiguous C–C Diaxes via Oxidative NHC Catalysis. ACS Catal 2023. [DOI: 10.1021/acscatal.2c05570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Si-Chen Zhang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi’an 710072, China
| | - Shengping Liu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi’an 710072, China
| | - Xia Wang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi’an 710072, China
| | - Shao-Jie Wang
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi’an 710072, China
| | - Hui Yang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Republic of Singapore 117543
| | - Lin Li
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi’an 710072, China
| | - Binmiao Yang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Republic of Singapore 117543
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Republic of Singapore 117543
| | - Yu Zhao
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Republic of Singapore 117543
| | - Shenci Lu
- Frontiers Science Center for Flexible Electronics (FSCFE), Shaanxi Institute of Flexible Electronics (SIFE) & Shaanxi Institute of Biomedical Materials and Engineering (SIBME), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi’an 710072, China
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49
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Liang Z, Li J, Wang L, Wei Z, Huang J, Wang X, Du D. Construction of Functionalized 2 H-Pyran-2-ones via N-Heterocyclic Carbene-Catalyzed [3 + 3] Annulation of Alkynyl Esters with Enolizable Ketones. J Org Chem 2023; 88:1836-1843. [PMID: 36696583 DOI: 10.1021/acs.joc.2c02392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A new synthesis of functionalized 2H-pyran-2-ones has been developed through N-heterocyclic carbene-catalyzed formal [3 + 3] annulation of alkynyl esters with enolizable ketones. The key to the success of this protocol relies on the use of an NHC instead of a tertiary amine as the catalyst. This protocol also features a broad substrate scope and mild metal-free conditions, offering simple and rapid access to the target molecules in a highly regioselective manner.
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Affiliation(s)
- Zheng Liang
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Jibin Li
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Lei Wang
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Zexuan Wei
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Jiahui Huang
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Xinrui Wang
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Ding Du
- State Key Laboratory of Natural Medicines, School of Science, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
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50
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Azaz T, Mourya H, Singh V, Ram B, Tiwari B. N-Heterocyclic Carbene-Catalyzed Enantioselective [3 + 2] Annulation of Enals with Vinyl Ketones. J Org Chem 2023; 88:1219-1226. [PMID: 36622160 DOI: 10.1021/acs.joc.2c01894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
An unprecedented N-heterocyclic carbene (NHC)-catalyzed enantioselective [3 + 2] annulation of enals with vinyl ketones has been achieved. Unlike chalcones, the β-unsubstituted enones, namely, vinyl ketones, have remained challenging in terms of reactivity, especially enantioselectivity. The disubstituted cyclopentenes were obtained in good yields and excellent stereoselectivities in the presence of Ti(OiPr)4.
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Affiliation(s)
- Tazeen Azaz
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS-Campus, Raebareli Road, Lucknow, Uttar Pradesh 226014, India.,Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India
| | - Hemlata Mourya
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS-Campus, Raebareli Road, Lucknow, Uttar Pradesh 226014, India
| | - Vikram Singh
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS-Campus, Raebareli Road, Lucknow, Uttar Pradesh 226014, India.,Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India
| | - Bali Ram
- Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India
| | - Bhoopendra Tiwari
- Department of Biological and Synthetic Chemistry, Centre of Biomedical Research, SGPGIMS-Campus, Raebareli Road, Lucknow, Uttar Pradesh 226014, India
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