1
|
Pankhade YA, Pandey R, Fatma S, Ahmad F, Anand RV. TfOH-Catalyzed Intramolecular Annulation of 2-(Aryl)-Phenyl-Substituted p-Quinone Methides under Continuous Flow: Total Syntheses of Selaginpulvilin I and Isoselagintamarlin A. J Org Chem 2022; 87:3363-3377. [PMID: 35107013 DOI: 10.1021/acs.joc.1c02980] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this article, we describe a convenient method to access 9-aryl fluorene derivatives through a TfOH-catalyzed intramolecular 1,6-conjugate arylation of 2-(aryl)-phenyl-substituted p-quinone methides (QMs) under continuous flow using the microreaction technique. This method was found to be very effective for most of the p-QMs, and the corresponding 9-aryl fluorene derivatives were obtained in moderate to excellent yields. Moreover, this protocol was further elaborated to the first total syntheses of selaginpulvilin I and isoselagintamarlin A.
Collapse
Affiliation(s)
- Yogesh A Pankhade
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, Punjab 140306, India
| | - Rajat Pandey
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, Punjab 140306, India
| | - Shaheen Fatma
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, Punjab 140306, India
| | - Feroz Ahmad
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, Punjab 140306, India
| | - Ramasamy Vijaya Anand
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, Punjab 140306, India
| |
Collapse
|
2
|
Bugaenko DI, Karchava AV, Yurovskaya MA. Transition metal-free cross-coupling reactions with the formation of carbon-heteroatom bonds. RUSSIAN CHEMICAL REVIEWS 2022. [DOI: 10.1070/rcr5022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
3
|
Nandy A, Sekar G. KO tBu-Promoted Halogen-Bond-Assisted Intramolecular C-S Cross-Coupling of o-Iodothioanilides for the Synthesis of 2-Substituted Benzothiazoles. J Org Chem 2021; 86:15825-15834. [PMID: 34644084 DOI: 10.1021/acs.joc.1c02023] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
An efficacious and mild KOtBu-promoted intramolecular C-S cross-coupling of ortho-iodothioanilides in conjunction with a catalytic quantity of phenanthroline as an additive has been described for the convenient synthesis of 2-substituted benzothiazoles. The methodology is suitable for attaining a wide variety of 2-alkyl- and 2-aryl-substituted benzothiazoles. Single-crystal XRD, DFT calculations, NMR, and UV studies suggest that halogen bonds between the units of ortho-iodothioanilides may assist in the electron transfer process.
Collapse
Affiliation(s)
- Anuradha Nandy
- Department of Chemistry, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600 036, India
| | - Govindasamy Sekar
- Department of Chemistry, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600 036, India
| |
Collapse
|
4
|
Ton SJ, Neumann KT, Nørby P, Skrydstrup T. Nickel-Mediated Alkoxycarbonylation for Complete Carbon Isotope Replacement. J Am Chem Soc 2021; 143:17816-17824. [PMID: 34643376 DOI: 10.1021/jacs.1c09170] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Many commercial drugs, as well as upcoming pharmaceutically active compounds in the pipeline, display aliphatic carboxylic acids or derivatives thereof as key structural entities. Synthetic methods for rapidly accessing isotopologues of such compounds are highly relevant for undertaking critical pharmacological studies. In this paper, we disclose a direct synthetic route allowing for full carbon isotope replacement via a nickel-mediated alkoxycarbonylation. Employing a nickelII pincer complex ([(N2N)Ni-Cl]) in combination with carbon-13 labeled CO, alkyl iodide, sodium methoxide, photocatalyst, and blue LED light, it was possible to generate the corresponding isotopically labeled aliphatic carboxylates in good yields. Furthermore, the developed methodology was applied to the carbon isotope substitution of several pharmaceutically active compounds, whereby complete carbon-13 labeling was successfully accomplished. It was initially proposed that the carboxylation step would proceed via the in situ formation of a nickellacarboxylate, generated by CO insertion into the Ni-alkoxide bond. However, preliminary mechanistic investigations suggest an alternative pathway involving attack of an open shell species generated from the alkyl halide to a metal ligated CO to generate an acyl NiIII species. Subsequent reductive elimination involving the alkoxide eventually leads to carboxylate formation. An excess of the alkoxide was essential for obtaining a high yield of the product. In general, the presented methodology provides a simple and convenient setup for the synthesis and carbon isotope labeling of aliphatic carboxylates, while providing new insights about the reactivity of the N2N nickel pincer complex applied.
Collapse
Affiliation(s)
- Stephanie J Ton
- Carbon Dioxide Activation Center (CADIAC), The Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus, Denmark
| | - Karoline T Neumann
- Carbon Dioxide Activation Center (CADIAC), The Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus, Denmark
| | - Peter Nørby
- Center for Materials Crystallography, Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus, Denmark
| | - Troels Skrydstrup
- Carbon Dioxide Activation Center (CADIAC), The Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus, Denmark
| |
Collapse
|
5
|
Kumar Y, Ila H. Synthesis of Substituted Benzo[b]thiophenes via Base-Promoted Domino Condensation–Intramolecular C–S Bond Formation. Org Lett 2021; 23:1698-1702. [DOI: 10.1021/acs.orglett.1c00085] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Yogendra Kumar
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India
| | - Hiriyakkanavar Ila
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India
| |
Collapse
|
6
|
Abstract
An efficient and practical transition metal free α-trideuteration of methylarenes was developed.
Collapse
Affiliation(s)
- Lin Tie
- Department of Chemistry
- University of Science and Technology of China
- Hefei
- China
| | - Xiang-Huan Shan
- Department of Chemistry
- University of Science and Technology of China
- Hefei
- China
| | - Jian-Ping Qu
- Institute of Advanced Synthesis
- School of Chemistry and Molecular Engineering
- Nanjing Tech University
- Nanjing 211816
- China
| | - Yan-Biao Kang
- Department of Chemistry
- University of Science and Technology of China
- Hefei
- China
| |
Collapse
|
7
|
Shan XH, Yang B, Qu JP, Kang YB. CuSO 4-Catalyzed dual annulation to synthesize O, S or N-containing tetracyclic heteroacenes. Chem Commun (Camb) 2020; 56:4063-4066. [PMID: 32162642 DOI: 10.1039/d0cc01172j] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this work, CuSO4 is utilized as a practical redox catalyst for tandem dual annulation in the synthesis of indole-fused tetracyclic heteroacenes, which are important skeletons in both medicinal chemistry and materials chemistry. The preparation of such skeletons in a convenient and efficient manner is in high demand. This method realizes the modular synthesis of benzofuro-, benzothieno-, and indoloindoles from abundant feedstocks such as 2-halobenzyl halides and nitrile derivatives in up to 99% yields, providing a rapid access to diverse indole-fused heteroacenes with biological or optoelectronic properties.
Collapse
Affiliation(s)
- Xiang-Huan Shan
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Bo Yang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Jian-Ping Qu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Yan-Biao Kang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
| |
Collapse
|
8
|
Saladrigas M, Puig J, Bonjoch J, Bradshaw B. Iron-Catalyzed Radical Intermolecular Addition of Unbiased Alkenes to Aldehydes. Org Lett 2020; 22:8111-8115. [PMID: 33017537 DOI: 10.1021/acs.orglett.0c03081] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intermolecular reductive radical coupling of aldehydes with nonactivated alkenes, employing metal hydride atom transfer (MHAT) catalysis with a combination of FeII and FeIII salts, is described. This constitutes the first use of aldehydes as viable acceptor groups in MHAT reactions. The insights gained in this study led to the reexamination of the previously reported intramolecular version of the reaction, and the addition of FeII salts allowed the development of a more efficient second-generation approach.
Collapse
Affiliation(s)
- Mar Saladrigas
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| | - Jordi Puig
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| | - Josep Bonjoch
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| | - Ben Bradshaw
- Laboratori de Quı́mica Orgànica, Facultat de Farmàcia, IBUB, Universitat de Barcelona, Av. Joan XXIII s/n, 08028-Barcelona, Spain
| |
Collapse
|
9
|
Duc DX. Recent Achievement in the Synthesis of Benzo[b]furans. Curr Org Synth 2020; 17:498-517. [PMID: 32586253 DOI: 10.2174/1570179417666200625212639] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/21/2020] [Accepted: 05/28/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Benzo[b]furan derivatives are oxygen-containing heterocyclic compounds consisting of fused benzene and furan rings and are present in a large number of natural and non-natural compounds. This class of compounds has a wide spectrum of biological activities, such as antiarrhythmic, anticancer, inflammatory, antioxidant, antimicrobial, and antiviral. Furthermore, benzo[b]furan derivatives have also been applied in various areas, such as organic electroluminescence device materials and organic dyes, photosensitizing material, organic synthesis as building blocks or intermediates. Because of a broad range of applicability, the synthesis of benzo[b]furan derivative has drawn great attention of chemists and many studies on the synthesis of this class of compounds have been reported recently. This review will give an overview of benzo[b]furan preparation based on studies dating back to the year 2012. OBJECTIVE In this review, recent development in the synthesis of benzo[b]furans are discussed. There has been increasingly new methodologies for the construction of benzo[b]furans skeleton to improve efficiency or develop environmentally friendly procedures. In some studies, reaction mechanisms were also outlined. CONCLUSION Many methods for the synthesis of benzo[b]furans have been reported recently. Most of them involve cyclization or cycloisomerization processes. Unquestionably, more imaginative strategies for the construction of benzo[b]furan skeleton will be established in the near future. Application of known methods to natural products or drug synthesis, on industrial scale for the synthesis of economically or medicinally important benzo[ b]furans will probably be paid attention to.
Collapse
Affiliation(s)
- Dau Xuan Duc
- Department of Chemistry, Vinh University, Vinh City, Vietnam
| |
Collapse
|
10
|
Li YW, Zheng HX, Yang B, Shan XH, Qu JP, Kang YB. tBuOK-Promoted Cyclization of Imines with Aryl Halides. Org Lett 2020; 22:4553-4556. [PMID: 32437166 DOI: 10.1021/acs.orglett.0c01615] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A transition-metal-free indole synthesis using radical coupling of 2-halotoluenes and imines via the later-stage C-N bond construction was reported for the first time. It includes an aminyl radical generation by C-H cleaving addition of 2-halotoluenes to imines via the carbanion radical relay and an intramolecular coupling of aryl halides with aminyl radicals. One standard condition can be used for all halides including F, Cl, Br, and I. No extra oxidant or transition metal is required.
Collapse
Affiliation(s)
- Ya-Wei Li
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Hong-Xing Zheng
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Bo Yang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiang-Huan Shan
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jian-Ping Qu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Yan-Biao Kang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| |
Collapse
|
11
|
Song L, Su Q, Lin X, Du Z, Xu H, Ouyang MA, Yao H, Tong R. Cascade Claisen and Meinwald Rearrangement for One-Pot Divergent Synthesis of Benzofurans and 2H-Chromenes. Org Lett 2020; 22:3004-3009. [DOI: 10.1021/acs.orglett.0c00770] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Liyan Song
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education), College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Qian Su
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education), College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Xi Lin
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education), College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Zhihui Du
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education), College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Huiyou Xu
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education), College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Ming-An Ouyang
- Key Laboratory of Biopesticide and Chemical Biology (Ministry of Education), College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Hongliang Yao
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Drug Synthesis and Evaluation Center, Guangdong Institute of Applied Biological Resources, Guangzhou, Guangdong 510260, China
| | - Rongbiao Tong
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, China
| |
Collapse
|
12
|
Zhang L, Cao T, Jiang H, Zhu S. Deconstructive Reorganization: De Novo Synthesis of Hydroxylated Benzofuran. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ling Zhang
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology 510640 Guangzhou China
| | - Tongxiang Cao
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology 510640 Guangzhou China
| | - Huanfeng Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology 510640 Guangzhou China
| | - Shifa Zhu
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology 510640 Guangzhou China
- State Key Laboratory of Elemento-Organic ChemistryNankai University 300071 Tianjing China
- Singfar Laboratories 510670 Guangzhou China
| |
Collapse
|
13
|
Zhang L, Cao T, Jiang H, Zhu S. Deconstructive Reorganization: De Novo Synthesis of Hydroxylated Benzofuran. Angew Chem Int Ed Engl 2020; 59:4670-4677. [PMID: 31961991 DOI: 10.1002/anie.201915212] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/18/2020] [Indexed: 12/26/2022]
Abstract
An unprecedented deconstructive reorganization strategy for the de novo synthesis of hydroxylated benzofurans from kojic acid- or maltol-derived alkynes is reported. In this reaction, both the benzene and furan rings were simultaneously constructed, whereas the pyrone moiety of the kojic acid or maltol was deconstructed and then reorganized into the benzene ring as a six-carbon component. Through this strategy, at least one free hydroxyl group was introduced into the benzene ring in a substitution-pattern tunable fashion without protection-deprotection and redox adjustment. With this method, a large number of hydroxylated benzofuran derivatives with different substitution-patterns have been prepared efficiently. This methodology has also been shown as the key step in a collective total synthesis of hydroxylated benzofuran-containing natural products (11 examples).
Collapse
Affiliation(s)
- Ling Zhang
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, 510640, Guangzhou, China
| | - Tongxiang Cao
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, 510640, Guangzhou, China
| | - Huanfeng Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, 510640, Guangzhou, China
| | - Shifa Zhu
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, 510640, Guangzhou, China.,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, 300071, Tianjing, China.,Singfar Laboratories, 510670, Guangzhou, China
| |
Collapse
|
14
|
Oschmann M, Johansson Holm L, Pourghasemi-Lati M, Verho O. Synthesis of Elaborate Benzofuran-2-carboxamide Derivatives through a Combination of 8-Aminoquinoline Directed C-H Arylation and Transamidation Chemistry. Molecules 2020; 25:E361. [PMID: 31952313 PMCID: PMC7024369 DOI: 10.3390/molecules25020361] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 12/20/2022] Open
Abstract
Herein, we present a short and highly modular synthetic route that involves 8-aminoquinoline directed C-H arylation and transamidation chemistry, and which enables access to a wide range of elaborate benzofuran-2-carboxamides. For the directed C-H arylation reactions, Pd catalysis was used to install a wide range of aryl and heteroaryl substituents at the C3 position of the benzofuran scaffold in high efficiency. Directing group cleavage and further diversification of the C3-arylated benzofuran products were then achieved in a single synthetic operation through the utilization of a one-pot, two-step transamidation procedure, which proceeded via the intermediate N-acyl-Boc-carbamates. Given the high efficiency and modularity of this synthetic strategy, it constitutes a very attractive method for generating structurally diverse collections of benzofuran derivatives for small molecule screening campaigns.
Collapse
Affiliation(s)
| | | | | | - Oscar Verho
- Arrhenius Laboratory, Department of Organic Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden; (M.O.); (L.J.H.); (M.P.-L.)
| |
Collapse
|
15
|
Tyagi A, Reshi NUD, Daw P, Bera JK. Palladium complexes with an annellated mesoionic carbene (MIC) ligand: catalytic sequential Sonogashira coupling/cyclization reaction for one-pot synthesis of benzofuran, indole, isocoumarin and isoquinolone derivatives. Dalton Trans 2020; 49:15238-15248. [DOI: 10.1039/d0dt02918a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A Pd(ii) complex containing a mesoionic carbene and phosphine ligands is an efficient catalyst for tandem coupling/cyclization reaction.
Collapse
Affiliation(s)
- Akshi Tyagi
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Noor U Din Reshi
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Prosenjit Daw
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Jitendra K. Bera
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| |
Collapse
|
16
|
Shan XH, Wang MM, Tie L, Qu JP, Kang YB. CuSO 4-Catalyzed Tandem C(sp 3)-H Insertion Cyclization of Toluenes with Isonitriles to Form Indoles. Org Lett 2019; 22:357-360. [PMID: 31887043 DOI: 10.1021/acs.orglett.9b03751] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A CuSO4-catalyzed tandem benzylic C-H insertion cyclization of toluene derivatives and isonitriles is described. The naturally abundant salt CuSO4 serves as a low-cost ligand-free redox catalyst. This reaction provides a practical modular synthesis of N-aryl indoles from isonitriles.
Collapse
Affiliation(s)
- Xiang-Huan Shan
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| | - Mei-Mei Wang
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| | - Lin Tie
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| | - Jian-Ping Qu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering , Nanjing Tech University , Nanjing 211816 , China
| | - Yan-Biao Kang
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| |
Collapse
|
17
|
Kumar Y, Ila H. Domino Synthesis of 2-Substituted Benzothiazoles by Base-Promoted Intramolecular C–S Bond Formation. Org Lett 2019; 21:7863-7867. [DOI: 10.1021/acs.orglett.9b02855] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Yogendra Kumar
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India
| | - Hiriyakkanavar Ila
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India
| |
Collapse
|
18
|
Niu YJ, Sui GH, Zheng HX, Shan XH, Tie L, Fu JL, Qu JP, Kang YB. Competing Dehalogenation versus Borylation of Aryl Iodides and Bromides under Transition-Metal-Free Basic Conditions. J Org Chem 2019; 84:10805-10813. [DOI: 10.1021/acs.joc.9b01350] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Yi-Jie Niu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Guo-Hui Sui
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Hong-Xing Zheng
- School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Xiang-Huan Shan
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lin Tie
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jia-Le Fu
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jian-Ping Qu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Yan-Biao Kang
- Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| |
Collapse
|
19
|
Wang MM, Sui GH, Cui XC, Wang H, Qu JP, Kang YB. Radical α,β-Dehydrogenation of Saturated Amides via α-Oxidation with TEMPO under Transition Metal-Free Conditions. J Org Chem 2019; 84:8267-8274. [PMID: 31188594 DOI: 10.1021/acs.joc.9b00872] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A transition metal-free radical process for the selective α,β-dehydrogenation of saturated amides under mild conditions is developed. Utilizing radical activation strategy, the challenging issue associated with the low α-acidity of amides is resolved. For the first time, α,β-unsaturated Weinreb amides and acrylamides could be efficiently prepared directly from corresponding saturated amides. Mechanistic studies confirm the radical nature of this transformation. Two gram scale α,β-dehydrogenation have also been performed to demonstrate the utility of this method.
Collapse
Affiliation(s)
- Mei-Mei Wang
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| | - Guo-Hui Sui
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials , Nanjing Tech University , Nanjing 211816 , China
| | - Xian-Chao Cui
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| | - Hui Wang
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| | - Jian-Ping Qu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials , Nanjing Tech University , Nanjing 211816 , China
| | - Yan-Biao Kang
- Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , China
| |
Collapse
|
20
|
Zhang Y, Huang C, Lin X, Hu Q, Hu B, Zhou Y, Zhu G. Modular Synthesis of Alkylarylazo Compounds via Iron(III)-Catalyzed Olefin Hydroamination. Org Lett 2019; 21:2261-2264. [PMID: 30869900 DOI: 10.1021/acs.orglett.9b00540] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel Fe-catalyzed olefin hydroamination with aryldiazo sulfones for accessing alkylarylazo compounds has been successfully developed. Aryldiazo sulfones are used as radical acceptors, and N-N double bonds will be regenerated when an arene sulfonyl group leaves. The reaction features mild reaction conditions and a broad substrate scope, allowing access to many azo compounds that would be difficult or perhaps impossible to access using other methods.
Collapse
Affiliation(s)
- Yan Zhang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| | - Chenchao Huang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| | - Xinru Lin
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| | - Qi Hu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| | - Boyue Hu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| | - Yulu Zhou
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| | - Gangguo Zhu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials , Zhejiang Normal University , 688 Yingbin Road , Jinhua 321004 , China
| |
Collapse
|
21
|
Deng G, Li M, Yu K, Liu C, Liu Z, Duan S, Chen W, Yang X, Zhang H, Walsh PJ. Synthesis of Benzofuran Derivatives through Cascade Radical Cyclization/Intermolecular Coupling of 2‐Azaallyls. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201812369] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Guogang Deng
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Minyan Li
- Roy and Diana Vagelos LaboratoriesDepartment of ChemistryUniversity of Pennsylvania 231 South 34th Street Philadelphia PA USA
| | - Kaili Yu
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Chunxiang Liu
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Zhengfen Liu
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Shengzu Duan
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Wen Chen
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Xiaodong Yang
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Hongbin Zhang
- Key Laboratory of Medicinal Chemistry for Natural ResourcesMinistry of Education and Yunnan ProvinceState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of Chemical Science and TechnologyYunnan University Kunming 650091 P. R. China
| | - Patrick J. Walsh
- Roy and Diana Vagelos LaboratoriesDepartment of ChemistryUniversity of Pennsylvania 231 South 34th Street Philadelphia PA USA
| |
Collapse
|
22
|
Deng G, Li M, Yu K, Liu C, Liu Z, Duan S, Chen W, Yang X, Zhang H, Walsh PJ. Synthesis of Benzofuran Derivatives through Cascade Radical Cyclization/Intermolecular Coupling of 2-Azaallyls. Angew Chem Int Ed Engl 2019; 58:2826-2830. [PMID: 30624843 DOI: 10.1002/anie.201812369] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 12/18/2018] [Indexed: 11/07/2022]
Abstract
Benzofurans are among the most popular structural units in bioactive natural products, however, the synthesis of such structures by radical cyclization cascade reactions is rare. Herein, we report a mild and broadly applicable method for the construction of complex benzofurylethylamine derivatives through a unique radical cyclization cascade mechanism. Single-electron transfer (SET) from 2-azaallyl anions to 2-iodo aryl allenyl ethers initiates a radical cyclization that is followed by intermolecular radical-radical coupling. This expedient approach enables the synthesis of a range of polycyclic benzofurans that would otherwise be difficult to prepare.
Collapse
Affiliation(s)
- Guogang Deng
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Minyan Li
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, USA
| | - Kaili Yu
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Chunxiang Liu
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Zhengfen Liu
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Shengzu Duan
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Wen Chen
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Xiaodong Yang
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Hongbin Zhang
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education and Yunnan Province, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China
| | - Patrick J Walsh
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, USA
| |
Collapse
|
23
|
Bugaenko DI, Dubrovina AA, Yurovskaya MA, Karchava AV. Synthesis of Indoles via Electron-Catalyzed Intramolecular C-N Bond Formation. Org Lett 2018; 20:7358-7362. [PMID: 30431287 DOI: 10.1021/acs.orglett.8b02784] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A new protocol for the preparation of N-substituted indole-3-carboxylates has been developed. The key C-N bond formation occurs under transition-metal-free conditions employing a t-BuOK/DMF system without special initiators or additives. Across a number of substrates, indoles were afforded in yields higher or comparable to those obtained under transition-metal-catalyzed conditions. While demonstrating high functional group tolerance, new conditions are particularly attractive for manufacturing halogenated indoles that cannot be made in a pure form using other metal-based catalytic methods.
Collapse
Affiliation(s)
- Dmitry I Bugaenko
- Department of Chemistry , Moscow State University , Moscow 119234 , Russia
| | | | | | | |
Collapse
|