1
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Unveiling the Chemistry and Synthetic Potential of Catalytic Cycloaddition Reaction of Allenes: A Review. MOLECULES (BASEL, SWITZERLAND) 2023; 28:molecules28020704. [PMID: 36677762 PMCID: PMC9860688 DOI: 10.3390/molecules28020704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/02/2023] [Accepted: 01/03/2023] [Indexed: 01/13/2023]
Abstract
Allenes with two carbon-carbon double bonds belong to a unique class of unsaturated hydrocarbons. The central carbon atom of allene is sp hybridized and forms two σ-bonds and two π-bonds with two terminal sp2 hybridized carbon atoms. The chemistry of allenes has been well documented over the last decades. They are more reactive than alkenes due to higher strain and exhibit significant axial chirality, thus playing a vital role in asymmetric synthesis. Over a variety of organic transformations, allenes specifically undergo classical metal catalyzed cycloaddition reactions to obtain chemo-, regio- and stereoselective cycloadducts. This review briefly describes different types of annulations including [2+2], [2+2+1], [3+2], [2+2+2], [4+2], [5+2], [6+2] cycloadditions using titanium, cobalt, rhodium, nickel, palladium, platinum, gold and phosphine catalyzed reactions along with a mechanistic study of some highlighted protocols. The synthetic applications of these reactions towards the synthesis of natural products such as aristeromycin, ent-[3]-ladderanol, waihoensene(-)-vindoline and (+)-4-epi-vindoline have also been described.
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2
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Yang X, Sun J, Huang X, Jin Z. Asymmetric Synthesis of Structurally Sophisticated Spirocyclic Pyrano[2,3- c]pyrazole Derivatives Bearing a Chiral Quaternary Carbon Center. Org Lett 2022; 24:5474-5479. [PMID: 35857420 DOI: 10.1021/acs.orglett.2c02211] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A carbene-catalyzed enantio- and diastereoselective [2 + 4] cycloaddition reaction is developed for quick and efficient access to structurally complex multicyclic pyrano[2,3-c]pyrazole molecules. The reaction tolerates a broad scope of substrates bearing various substitution patterns, with the multicyclic pyrano[2,3-c]pyrazole products afforded in generally good to excellent yields and optical purities. The chiral molecules obtained from this approach has found promising applications in the development of novel bacteriacides for plant protection.
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Affiliation(s)
- Xiaoqun Yang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Jun Sun
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Xuan Huang
- International Joint Research Center for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Zhichao Jin
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
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3
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Song M, Zhao J, Li EQ. Recent advances in tertiary amine Lewis base-promoted cycloadditions of allenoates. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2021.11.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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4
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Yi MH, Jin HS, Wang RB, Zhao LM. Copper-Catalyzed Cascade Annulation of o-Hydroxyphenyl Propargylamines with Pyrazolin-5-ones to Access Pyrano[2,3- c]pyrazoles. J Org Chem 2022; 87:5795-5803. [PMID: 35442039 DOI: 10.1021/acs.joc.2c00122] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An efficient copper-catalyzed cascade annulation of o-hydroxyphenyl propargylamines and pyrazolin-5-ones is described. This methodology leads to the rapid assembly of a series of valuable pyrano[2,3-c]pyrazoles with good yields across a wide range of substrates in a simple fashion. This novel reaction involves the formation of alkynyl ortho-quinone methides, a 1,4-conjugate addition, and a subsequent 6-endo cyclization process. The mechanistic elucidation is well supported by control experiment and literature precedents.
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Affiliation(s)
- Meng-Hao Yi
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China
| | - Hai-Shan Jin
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China
| | - Ru-Bing Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Li-Ming Zhao
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.,State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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5
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Meng Y, Chen L, Li EQ. Recent Advances in Lewis Base-Catalysed Chemo-, Diastereo- and Enantiodivergent Reactions of Electron-deficient Olefins and Alkynes. CHEM REC 2021; 22:e202100276. [PMID: 34962071 DOI: 10.1002/tcr.202100276] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/07/2021] [Indexed: 01/28/2023]
Abstract
Lewis base catalysis provides powerful synthetic strategies for the selective construction of carbon-carbon and carbon-heteroatom bonds. Thus continuous efforts have been deployed to develop effective methodologies involving Lewis base catalysis. The nucleophilicity and steric hindrance of Lewis base catalyst often plays a major role in catalytic reactivity and selectivity in the reaction. In the past decades, tremendous progress has been made in the divergent construction of valuable motifs under Lewis base catalysis. In this review, we provide a comprehensive and updated summary of Lewis base-catalysed chemo-, diastereo- and enantiodivergent reaction, as well as the related mechanism will be highlighted in detail.
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Affiliation(s)
- Yinggao Meng
- College of Chemistry, Green Catalysis Center, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Lihui Chen
- College of Chemistry, Green Catalysis Center, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Er-Qing Li
- College of Chemistry, Green Catalysis Center, Zhengzhou University, Zhengzhou, 450001, P. R. China
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6
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Wang S, Lin JJ, Cui X, Li JP, Huang C. Controllable Synthesis of Two Isomers 4 H-Chromene and 2,8-Dioxabicyclo[3.3.1]nonane Derivatives under Catalyst-Free Conditions. J Org Chem 2021; 86:16396-16408. [PMID: 34781678 DOI: 10.1021/acs.joc.1c01762] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A one-pot method for the selective synthesis of two isomers 4H-chromene and 2,8-dioxabicyclo[3.3.1]nonane derivatives was developed without a catalyst and using EtOH/H2O (4:1, v/v) as the solvent. The reaction was conducted under mild conditions, with forming multiple chemical bonds in one pot and high atom economy, and only a stoichiometric amount of H2O is produced as the byproduct. Its selectivity was controlled by thermodynamics and kinetics, and the reasons for the transformation of the two structures are also discussed.
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Affiliation(s)
- Shuang Wang
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, School of Chemistry and Environment, Yunnan Minzu University, Kunming 650500, People's Republic of China
| | - Jun-Jie Lin
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, School of Chemistry and Environment, Yunnan Minzu University, Kunming 650500, People's Republic of China
| | - Xin Cui
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, School of Chemistry and Environment, Yunnan Minzu University, Kunming 650500, People's Republic of China
| | - Jing-Peng Li
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, School of Chemistry and Environment, Yunnan Minzu University, Kunming 650500, People's Republic of China
| | - Chao Huang
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, School of Chemistry and Environment, Yunnan Minzu University, Kunming 650500, People's Republic of China
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7
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Hou R, Wang Z, Peng J, Yuan Y, Zhang J, Wang D, Sun T. Conformational Preferences of Allene Ketones in Lewis Base Catalysis: Synthesis of 4
H
‐Pyrans and 3,4‐Dihydro‐2
H
‐pyrans
via α
‐Regioselective [4+2] Annulations of
γ
‐Substituted Allene Ketones and Activated Alkenes. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Rongrong Hou
- School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology Wuhan 430070 P. R. China
| | - Ziyu Wang
- SDU-ANU Joint Science College Shandong University Weihai 264209 P. R. China
| | - Jia Peng
- School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology Wuhan 430070 P. R. China
| | - Ye Yuan
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 P. R. China
| | - Jingli Zhang
- School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology Wuhan 430070 P. R. China
| | - Du Wang
- School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology Wuhan 430070 P. R. China
| | - Taolei Sun
- School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology Wuhan 430070 P. R. China
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8
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Anwar S, Lin LT, Srinivasadesikan V, Gudise VB, Chen K. [3+2] regioselective annulation reaction of 2-arylidene-1,3-indandiones towards synthesis of spirocyclopentenes: understanding the mechanism of γ-attack vs. α-attack using DFT studies. RSC Adv 2021; 11:38648-38653. [PMID: 35493224 PMCID: PMC9044273 DOI: 10.1039/d1ra07165c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 11/19/2021] [Indexed: 12/18/2022] Open
Abstract
A regioselective [3+2] cyclisation reaction between 2-arylidene-1,3-indanedione and ethyl 2,3-butadienoate catalysed by triphenylphosphine has been demonstrated to synthesize functionalised spirocyclic cyclopentenes. The reaction tolerated various electron-rich and electron-deficient aryl substituted 2-arylidene-1,3-indanediones with high to excellent chemical yields (up to 99%) and moderate to good regioselectivity (up to 5 : 1). DFT studies have also been carried out to understand the regioselective nature of this reaction. The results of Frontier molecular orbital calculations and the activation energy (Ea) favour the formation of compound 3avia γ-attack compared to that of 4avia α-attack. A [3+2] annulation protocol for the construction of functionalized spirocyclopentenes utilizing 1,3-indanedione derived benzylidene-1,3-indanedione and ethyl-2,3-butadienoate at room temperature was developed.![]()
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Affiliation(s)
- Shaik Anwar
- Division of Chemistry, Department of Sciences and Humanities, Vignan's Foundation for Science Technology and Research-VFSTR (Deemed to be University) Vadlamudi-522 213 Guntur Andhra Pradesh India http://www.vignan.ac.in/bshanwar.php +91-8632344700.,Department of Chemistry, National Taiwan Normal University 88 Sec. 4, TingChow Road Taipei Taiwan 116 ROC +86-2-29324249 +86-2-7734-6124
| | - Li-Tzu Lin
- Department of Chemistry, National Taiwan Normal University 88 Sec. 4, TingChow Road Taipei Taiwan 116 ROC +86-2-29324249 +86-2-7734-6124
| | - V Srinivasadesikan
- Division of Chemistry, Department of Sciences and Humanities, Vignan's Foundation for Science Technology and Research-VFSTR (Deemed to be University) Vadlamudi-522 213 Guntur Andhra Pradesh India http://www.vignan.ac.in/bshanwar.php +91-8632344700
| | - Veera Babu Gudise
- Division of Chemistry, Department of Sciences and Humanities, Vignan's Foundation for Science Technology and Research-VFSTR (Deemed to be University) Vadlamudi-522 213 Guntur Andhra Pradesh India http://www.vignan.ac.in/bshanwar.php +91-8632344700
| | - Kwunmin Chen
- Department of Chemistry, National Taiwan Normal University 88 Sec. 4, TingChow Road Taipei Taiwan 116 ROC +86-2-29324249 +86-2-7734-6124
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9
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Abstract
Organocatalysts are abundantly used for various transformations, particularly to obtain highly enantio- and diastereomeric pure products by controlling the stereochemistry. These applications of organocatalysts have been the topic of several reviews. Organocatalysts have emerged as one of the very essential areas of research due to their mild reaction conditions, cost-effective nature, non-toxicity, and environmentally benign approach that obviates the need for transition metal catalysts and other toxic reagents. Various types of organocatalysts including amine catalysts, Brønsted acids, and Lewis bases such as N-heterocyclic carbene (NHC) catalysts, cinchona alkaloids, 4-dimethylaminopyridine (DMAP), and hydrogen bond-donating catalysts, have gained renewed interest because of their regioselectivity. In this review, we present recent advances in regiodivergent reactions that are governed by organocatalysts. Additionally, we briefly discuss the reaction pathways of achieving regiodivergent products by changes in conditions such as solvents, additives, or the temperature.
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10
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Zhang X, Gao Y, Liu Y, Miao Z. Diastereoselective Synthesis of Tetrabenzohydrofuran Spirooxindoles via Diethyl Phosphite-Mediated Coupling of Isatins with o-Quinone Methides. J Org Chem 2021; 86:8630-8640. [PMID: 34162210 DOI: 10.1021/acs.joc.1c00336] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diethyl phosphite-initiated coupling of isatins with o-quinone methides (o-QMs) is reported. This reaction involves a cascade transformation initiated by base-promoted addition of phosphite to isatins, followed by [1,2]-phospha-Brook rearrangement. This generates α-phosphonyloxy enolates that are subsequently intercepted by o-QMs and finally intramolecular ring closure. This protocol was used to diastereoselectively synthesize a range of trans-tetrabenzohydrofuran spirooxindoles in moderate to good yields with moderate to excellent diastereoselectivities.
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Affiliation(s)
- Xiyuan Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China
| | - Yanfeng Gao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China
| | - Yitong Liu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China
| | - Zhiwei Miao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, China
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11
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Cheng C, Sun X, Miao Z. A PPh 3-catalyzed sequential annulation reaction to construct cyclopentane-fused dihydropyrazolone-pyrrolidinediones. Org Biomol Chem 2021; 18:5577-5581. [PMID: 32662811 DOI: 10.1039/d0ob00815j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A PPh3-catalyzed sequential cycloaddition of maleimides with unsaturated pyrazolones has been developed. This protocol provides a simple and practical strategy for the construction of dispirocyclopentyl-[dihydropyrazolone-pyrrolidinedione] pyrrolidinedione skeletons containing five contiguous stereogenic centers, including two spiro-quaternary centers, with moderate yields (34-73%) and excellent diastereoselectivities (>20 : 1).
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Affiliation(s)
- Cheng Cheng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China.
| | - Xiaobin Sun
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China.
| | - Zhiwei Miao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China. and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, China
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12
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Gao Y, Zhang X, Zhang X, Miao Z. Catalytic Asymmetric Construction of a 1,2,4-Benzotriazepine Skeleton via Diastereo- and Enantioselective Decarboxylative [4 + 3] Cyclization. Org Lett 2021; 23:2415-2420. [PMID: 33709719 DOI: 10.1021/acs.orglett.1c00073] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We have developed a protocol for palladium-catalyzed decarboxylative [4 + 3] cycloaddition reactions between 4-vinyl benzoxazinanones and azomethine imines to generate moderate to good yields of structurally diverse 1,2,4-benzotriazepines bearing two stereogenic centers with good to excellent stereoselectivities. This protocol not only addresses the challenge of asymmetrically constructing compounds with a 1,2,4-benzotriazepine skeleton but also demonstrates the utility of decarboxylative cycloadditions for the synthesis of enantioenriched polycyclic compounds.
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Affiliation(s)
- Yanfeng Gao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China
| | - Xuange Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China
| | - Xiyuan Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China
| | - Zhiwei Miao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Weijin Road 94, Tianjin 300071, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, China
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13
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Du J, Wu J, Zhu L, Ren X, Jiang C, Wang T. Bifunctional Phosphonium Salt‐catalyzed Enantioselective [4+2] Annulation of Isoindigos with Allenes: Access to Complex Heterocycles with Centerpiece of 4
H
‐Pyrans. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000150] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Juan Du
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of ChemistrySichuan University 29 Wangjiang Road Chengdu 610064 People's Republic of China
| | - Jia‐Hong Wu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of ChemistrySichuan University 29 Wangjiang Road Chengdu 610064 People's Republic of China
| | - Lixiang Zhu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of ChemistrySichuan University 29 Wangjiang Road Chengdu 610064 People's Republic of China
| | - Xiaoyu Ren
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of ChemistrySichuan University 29 Wangjiang Road Chengdu 610064 People's Republic of China
| | - Chunhui Jiang
- School of Environmental and Chemical EngineeringJiangsu University of Science and Technology 2 Mengxi Road Zhenjiang 212003 People's Republic of China
| | - Tianli Wang
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of ChemistrySichuan University 29 Wangjiang Road Chengdu 610064 People's Republic of China
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14
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Zhang ZB, Yang Y, Yu ZX, Xia JB. Lewis Base-Catalyzed Amino-Acylation of Arylallenes via C–N Bond Cleavage: Reaction Development and Mechanistic Studies. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01000] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Zheng-Bing Zhang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Synthesis, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), University of Chinese Academy of Sciences, Chinese Academy of Sciences, Lanzhou 730000, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yusheng Yang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Zhi-Xiang Yu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Ji-Bao Xia
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Synthesis, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), University of Chinese Academy of Sciences, Chinese Academy of Sciences, Lanzhou 730000, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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15
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Luo W, Shao B, Li J, Song D, Yi X, Ling F, Zhong W. Divergent synthesis of spirocyclopentene-pyrazolones and pyrano[2,3-c]-pyrazoles via Lewis base controlled annulation reactions. Tetrahedron Lett 2019. [DOI: 10.1016/j.tetlet.2019.151206] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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16
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Dočekal V, Formánek B, Císařová I, Veselý J. A formal [4 + 2] cycloaddition of sulfur-containing alkylidene heterocycles with allenic compounds. Org Chem Front 2019. [DOI: 10.1039/c9qo00886a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A convenient enantioselective synthesis of sulfur heterocycles containing the dihydro-2H-pyran moiety by quinidine catalyzed formal [4 + 2] cycloaddition of 3-alkylidene benzo[b]thiophenes and allenoates is reported.
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Affiliation(s)
- Vojtěch Dočekal
- Department of Organic Chemistry
- Faculty of Science
- Charles University
- 128 43 Prague 2
- Czech Republic
| | - Bedřich Formánek
- Department of Organic Chemistry
- Faculty of Science
- Charles University
- 128 43 Prague 2
- Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry
- Faculty of Science
- Charles University
- 128 43 Prague 2
- Czech Republic
| | - Jan Veselý
- Department of Organic Chemistry
- Faculty of Science
- Charles University
- 128 43 Prague 2
- Czech Republic
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