1
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Paul B, Kundu S. The use of methanol as a C1 building block. Nat Protoc 2024; 19:2358-2385. [PMID: 38664579 DOI: 10.1038/s41596-024-00978-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 02/02/2024] [Indexed: 08/09/2024]
Abstract
Methanol is a key building block in the chemical industry. In recent years, it has been used as a C1 source in various organic transformations in the presence of a transition-metal catalyst. This protocol describes the ruthenium- and cobalt-catalyzed utilization of methanol in different types of methylation reactions and heterocycle synthesis. Initially, we describe the synthesis of tridentate ligands (L1-L3) and their corresponding Ru(II) complexes (Ru-1, -2 and -3) and then detail how to apply these Ru(II) complexes and Co/PP3 (PP3 = P(CH2CH2PPh2)3) in various methanol dehydrogenative coupling reactions. We discuss six types of transformations by using methanol or a methanol/water mixture. The experimental setup for all the catalytic reactions is similar and involves adding all the respective reagents and solvents to an argon-filled pressure tube, which is sealed (by screw cap) and refluxed at the indicated temperature before the desired products are isolated and characterized. The catalytic systems described in this protocol work well for both small-scale and preparative-scale synthesis of various N-methylated amines/amides, C-methylated products and quinazolinones. These catalytic reactions are greener and more sustainable than conventional synthesis methods, with only H2 and/or H2O as by-products, and we evaluate the 'green chemistry metrics' for a typical substrate. The total time required for the catalytic experiments described in this protocol is 16-28 h, and the operation time is 4 h. An average level of expertise in organic synthesis is required to carry out these protocols.
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Affiliation(s)
- Bhaskar Paul
- Department of Chemistry, University of Oxford, Oxford, UK.
- Department of Chemistry, Indian Institute of Technology, Kanpur, India.
| | - Sabuj Kundu
- Department of Chemistry, Indian Institute of Technology, Kanpur, India.
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2
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Templ J, Schnürch M. A Guide for Mono-Selective N-Methylation, N-Ethylation, and N-n-Propylation of Primary Amines, Amides, and Sulfonamides and Their Applicability in Late-Stage Modification. Chemistry 2024; 30:e202304205. [PMID: 38353032 DOI: 10.1002/chem.202304205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Indexed: 03/06/2024]
Abstract
This review provides a comprehensive overview of mono-alkylation methodologies targeting crucial nitrogen moieties - amines, amides, and sulfonamides - found in organic building blocks and pharmaceuticals. Emphasizing the intersection of chemical precision with drug discovery, the central challenge addressed is achieving one-pot mono-selective short-chain N-alkylations (methylations, ethylations, and n-propylations), preventing undesired overalkylation. Additionally, sustainable, safe, and benign alternatives to traditional alkylating agents, including alcohols, carbon dioxide, carboxylic acids, nitriles, alkyl phosphates, quaternary ammonium salts, and alkyl carbonates, are explored. This review, categorized by the nature of the alkylating agent, aids researchers in selecting suitable methods for mono-selective N-alkylation.
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Affiliation(s)
- Johanna Templ
- Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163, 1060, Vienna, Austria
| | - Michael Schnürch
- Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163, 1060, Vienna, Austria
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3
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Vil’ VA, Barsegyan YA, Kuhn L, Terent’ev AO, Alabugin IV. Creating, Preserving, and Directing Carboxylate Radicals in Ni-Catalyzed C(sp 3)–H Acyloxylation of Ethers, Ketones, and Alkanes with Diacyl Peroxides. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Affiliation(s)
- Vera A. Vil’
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky Prospect, Moscow 119991, Russian Federation
| | - Yana A. Barsegyan
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky Prospect, Moscow 119991, Russian Federation
| | - Leah Kuhn
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Fl 32306, United States
| | - Alexander O. Terent’ev
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky Prospect, Moscow 119991, Russian Federation
| | - Igor V. Alabugin
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Fl 32306, United States
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4
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Zhang Z, Chen X, Li XS, Wang CT, Niu ZJ, Zhang BS, Liu XY, Liang YM. Ortho C–H Hydroxyalkylation or Methylation of Aryl Iodides by Ethers and TMSI via a Catellani Strategy. Org Lett 2022; 24:6897-6902. [DOI: 10.1021/acs.orglett.2c02425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhe Zhang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Xi Chen
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Xue-Song Li
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Cui-Tian Wang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Zhi-Jie Niu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Bo-Sheng Zhang
- College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China
| | - Xue-Yuan Liu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Yong-Min Liang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
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5
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Ji H, Zhan H, Chen S, Fang Z, Zhang Q, Li D. Copper‐catalyzed C(sp
3
)−H/N−H Cross Dehydrogenative Coupling Between Toluene Derivatives and Picolinamides. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202200454] [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)
- Huihui Ji
- New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base School of Materials and Chemical Engineering Hubei University of Technology Wuhan 430068 China
| | - Hongju Zhan
- Hubei Provincial Key Laboratory of Drug Synthesis and Optimization Jingchu University of Technology Jingmen 448000 China
| | - Shumin Chen
- Hubei Provincial Key Laboratory of Drug Synthesis and Optimization Jingchu University of Technology Jingmen 448000 China
| | - Zeguo Fang
- New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base School of Materials and Chemical Engineering Hubei University of Technology Wuhan 430068 China
| | - Qian Zhang
- New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base School of Materials and Chemical Engineering Hubei University of Technology Wuhan 430068 China
| | - Dong Li
- New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base School of Materials and Chemical Engineering Hubei University of Technology Wuhan 430068 China
- Hubei Provincial Key Laboratory of Drug Synthesis and Optimization Jingchu University of Technology Jingmen 448000 China
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6
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Xu XH, Hao EJ, Shi Z, Dong ZB. Easy S-Alkylation of Arylthioureas and 2-Mercaptobenzothiazoles Using Tetraalkylammonium Salts under Transition-Metal-Free Conditions. J Org Chem 2022; 87:9675-9687. [PMID: 35896442 DOI: 10.1021/acs.joc.2c00728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A highly-efficient and practical method for S-alkylation of arylthioureas was reported. Using tetraalkylammonium salts as alkylation reagents, a series of 68 S-substituted aryl-isothioureas were obtained in good to excellent yields under transition-metal-free conditions. The protocol features simple performance, broad functional group tolerance, good to excellent yields, and easily available starting materials, showing potential synthetic value for the preparation of diverse biologically or pharmaceutically active compounds.
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Affiliation(s)
- Xiao-Hu Xu
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Er-Jun Hao
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
| | - Zhen Shi
- Hubei Key Laboratory of Biologic Resources Protection and Utilization, Hubei Minzu University, Enshi 445000, China
| | - Zhi-Bing Dong
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, China.,School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China.,Key Laboratory of Green Chemical Process, Ministry of Education, Wuhan Institute of Technology, Wuhan 430205, China.,Engineering Research Center of Phosphorus Resources Development and Utilization, Ministry of Education, Wuhan Institute of Technology, Wuhan 430205, China.,Hubei Key Laboratory of Biologic Resources Protection and Utilization, Hubei Minzu University, Enshi 445000, China
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7
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Yang QL, Liu Y, Liang L, Li ZH, Qu GR, Guo HM. Facilitating Rh-Catalyzed C-H Alkylation of (Hetero)arenes and 6-Arylpurine Nucleosides (Nucleotides) with Electrochemistry. J Org Chem 2022; 87:6161-6178. [PMID: 35438486 DOI: 10.1021/acs.joc.2c00391] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An electrochemical approach to promote the ortho-C-H alkylation of (hetero)arenes via rhodium catalysis under mild conditions is described. This approach features mild conditions with high levels of regio- and monoselectivity that tolerate a variety of aromatic and heteroaromatic groups and offers a widely applicable method for late-stage diversification of complex molecular architectures including tryptophan, estrone, diazepam, nucleosides, and nucleotides. Alkyl boronic acids and esters and alkyl trifluoroborates are demonstrated as suitable coupling partners. The isolation of key rhodium intermediates and mechanistic studies provided strong support for a rhodium(III/IV or V) regime.
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Affiliation(s)
- Qi-Liang Yang
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Ying Liu
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Lei Liang
- School of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
| | - Zhi-Hao Li
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Gui-Rong Qu
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Hai-Ming Guo
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
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8
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Gao Q, Sun Z, Wu M, Guo Y, Han X, Yan J, Ha MN, Le QM, Xu Y. Di- tert-butyl peroxide as an effective two-carbon unit in oxidative radical cyclization toward 7-methylazolo[1,5- a]pyrimidines. Org Chem Front 2022. [DOI: 10.1039/d2qo00381c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An unexpected oxidative radical cyclization with DTBP as the C2 cyclic unit enables the assembly of privileged 7-methylazolo[1,5-a]pyrimidines.
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Affiliation(s)
- Qinghe Gao
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China
| | - Zhenhua Sun
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China
| | - Manman Wu
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China
| | - Yimei Guo
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China
| | - Xinya Han
- School of Chemistry and Chemical Engineering, Anhui University of Technology, Maanshan, Anhui 243002, P. R. China
| | - Jufen Yan
- School of Chemistry and Chemical Engineering, Anhui University of Technology, Maanshan, Anhui 243002, P. R. China
| | - Minh Ngoc Ha
- VNU Key Laboratory of Advanced Materials for Green Growth, Faculty of Chemistry, University of Science, Vietnam National University, Hanoi 100000, Vietnam
| | - Quynh Mai Le
- Department of Plant Science, Faculty of Biology, University of Science, Vietnam National University, Hanoi 100000, Vietnam
| | - Yongtao Xu
- School of Medical Engineering, Henan International Joint Laboratory of Neural Information analysis and Drug Intelligent Design, Xinxiang Medical University, Xinxiang, Henan 453003, P. R. China
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9
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Paul B, Maji M, Panja D, Kundu S. Cobalt Catalyzed N‐Methylation of Amides using Methanol. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100678] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Bhaskar Paul
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 Uttar Pradesh (U.P. India
- Department of Chemistry University of California at Riverside Riverside California 92521 United States
| | - Milan Maji
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 Uttar Pradesh (U.P. India
| | - Dibyajyoti Panja
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 Uttar Pradesh (U.P. India
| | - Sabuj Kundu
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 Uttar Pradesh (U.P. India
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10
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Kang QQ, Zhang WK, Ge GP, Zheng H, Wei WT. The construction of benzimidazo[2,1- a]isoquinolin-6(5 H)-ones from N-methacryloyl-2-phenylbenzoimidazoles through radical strategies. Org Biomol Chem 2021; 19:8874-8885. [PMID: 34610071 DOI: 10.1039/d1ob01465j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Benzimidazo[2,1-a]isoquinolin-6(5H)-one constitutes a structurally unique class of tetracyclic N-heterocycles that are found throughout a myriad of biologically active natural products, pharmaceutical compounds, and functional materials. Various synthetic routes for the preparation of benzimidazo[2,1-a]isoquinolin-6(5H)-ones have been reported. In particular, the use of N-methacryloyl-2-phenylbenzoimidazoles to construct benzimidazo[2,1-a]isoquinolin-6(5H)-ones through various radical strategies have attracted widespread attention due to the versatility and simple preparation of raw materials, as well as the step-economy and mild reaction conditions. Using representative examples, we highlight significant progress in the synthesis of benzimidazo[2,1-a]isoquinolin-6(5H)-ones, including the selection of the catalytic system, substrate scope, mechanistic understanding, and applications. The contents of this review focus on the development of C-, S-, P-, and Si-centered radical addition-intramolecular cyclization strategies.
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Affiliation(s)
- Qing-Qing Kang
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang, 315211, China.
| | - Wei-Kang Zhang
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang, 315211, China.
| | - Guo-Ping Ge
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang, 315211, China.
| | - Hongxing Zheng
- Institution of Functional Organic Molecules and Materials, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng, 252059, China
| | - Wen-Ting Wei
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang, 315211, China.
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11
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12
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Huang J, Chen Z, Wu J. Recent Progress in Methyl-Radical-Mediated Methylation or Demethylation Reactions. ACS Catal 2021. [DOI: 10.1021/acscatal.1c02010] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Jiapian Huang
- Key Laboratory of Functional Small Organic Molecules, Ministry of Education, and Jiangxi Key Laboratory of Green Chemistry, College of Chemistry & Chemical Engineering, Jiangxi Normal University, 99 Ziyang Road, Nanchang, Jiangxi 330022, P. R. China
- School of Pharmaceutical and Materials Engineering & Institute for Advanced Studies, Taizhou University, 1139 Shifu Avenue, Taizhou 318000, China
| | - Zhiyuan Chen
- Key Laboratory of Functional Small Organic Molecules, Ministry of Education, and Jiangxi Key Laboratory of Green Chemistry, College of Chemistry & Chemical Engineering, Jiangxi Normal University, 99 Ziyang Road, Nanchang, Jiangxi 330022, P. R. China
| | - Jie Wu
- School of Pharmaceutical and Materials Engineering & Institute for Advanced Studies, Taizhou University, 1139 Shifu Avenue, Taizhou 318000, China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, China
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13
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Pan C, Yuan C, Yu JT. Peroxide-mediated synthesis of benzimidazo[2,1- a]isoquinoline-6(5 H)-ones via cascade methylation/ethylation and intramolecular cyclization. Org Biomol Chem 2021; 19:619-626. [PMID: 33367428 DOI: 10.1039/d0ob02383c] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A metal-free oxidative radical methylation/arylation of 2-arylbenzoimidazoles with DTBP as the oxidant and methyl radical source was developed. The reaction proceeds through a sequential methyl radical addition/cyclization pathway and affords a series of methyl functionalized benzimidazo[2,1-a]isoquinoline-6(5H)-ones in moderate to good yields. Besides, the ethylation/arylation of 2-arylbenzoimidazoles was also achieved with DTAP.
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Affiliation(s)
- Changduo Pan
- School of Chemical and Environmental Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China.
| | - Cheng Yuan
- School of Chemical and Environmental Engineering, Jiangsu University of Technology, Changzhou 213001, P. R. China.
| | - Jin-Tao Yu
- School of Petrochemical Engineering, Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, Changzhou University, Changzhou 213164, P. R. China.
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14
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Studies on the ɑ-lithiation-in situ intramolecular nucleophilic addition reactions of 2-acyl-N-sulfonylpyrroles. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.152907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Aynetdinova D, Callens MC, Hicks HB, Poh CYX, Shennan BDA, Boyd AM, Lim ZH, Leitch JA, Dixon DJ. Installing the “magic methyl” – C–H methylation in synthesis. Chem Soc Rev 2021; 50:5517-5563. [DOI: 10.1039/d0cs00973c] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Following notable cases of remarkable potency increases in methylated analogues of lead compounds, this review documents the state-of-the-art in C–H methylation technology.
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Affiliation(s)
- Daniya Aynetdinova
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | - Mia C. Callens
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | - Harry B. Hicks
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | - Charmaine Y. X. Poh
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | | | - Alistair M. Boyd
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | - Zhong Hui Lim
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | - Jamie A. Leitch
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
| | - Darren J. Dixon
- Department of Chemistry
- University of Oxford
- Chemistry Research Laboratory
- Oxford
- UK
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16
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Che S, Zhu Q, Luo Z, Lian Y, Zhao Z. Copper-catalyzed oxidative methylation of sulfonamides by dicumyl peroxide. SYNTHETIC COMMUN 2020. [DOI: 10.1080/00397911.2020.1859118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Shiying Che
- College of Pharmacy, Shaanxi University of Chinese Medicine, Shaanxi, P.R. China
- School of Chemistry and Materials Science, Huaihua University, Huaihua, P.R. China
- Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province, Huaihua University, Huaihua, P.R. China
| | - Qiao Zhu
- College of Pharmacy, Shaanxi University of Chinese Medicine, Shaanxi, P.R. China
- School of Chemistry and Materials Science, Huaihua University, Huaihua, P.R. China
- Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province, Huaihua University, Huaihua, P.R. China
| | - Zhenghong Luo
- School of Chemistry and Materials Science, Huaihua University, Huaihua, P.R. China
| | - Yan Lian
- School of Chemistry and Materials Science, Huaihua University, Huaihua, P.R. China
| | - Zijian Zhao
- College of Pharmacy, Shaanxi University of Chinese Medicine, Shaanxi, P.R. China
- School of Chemistry and Materials Science, Huaihua University, Huaihua, P.R. China
- Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province, Huaihua University, Huaihua, P.R. China
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17
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Cheng HG, Pu M, Kundu G, Schoenebeck F. Selective Methylation of Amides, N-Heterocycles, Thiols, and Alcohols with Tetramethylammonium Fluoride. Org Lett 2020; 22:331-334. [PMID: 31834810 DOI: 10.1021/acs.orglett.9b04400] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We herein disclose the use of tetramethylammonium fluoride (TMAF) as a direct and selective methylating agent of a variety of amides, indoles, pyrroles, imidazoles, alcohols, and thiols. The method is characterized by operational simplicity, wide scope, and ease of purification. Our computational studies suggest a concerted methylation-deprotonation as the preferred reaction pathway.
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Affiliation(s)
- Hong-Gang Cheng
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
| | - Maoping Pu
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
| | - Gourab Kundu
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
| | - Franziska Schoenebeck
- Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany
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18
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Jin S, Yao H, Lin S, You X, Yang Y, Yan Z. Peroxide-mediated site-specific C–H methylation of imidazo[1,2-a]pyridines and quinoxalin-2(1H)-ones under metal-free conditions. Org Biomol Chem 2020; 18:205-210. [DOI: 10.1039/c9ob02328c] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
An effective approach to realize the direct methylation of imidazo[1,2-a]pyridines and quinoxalin-2(1H)-ones with peroxides under metal-free conditions is described.
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Affiliation(s)
- Shengzhou Jin
- Department of Chemistry
- Nanchang University
- Nanchang
- P. R. China
| | - Hua Yao
- Department of Chemistry
- Nanchang University
- Nanchang
- P. R. China
| | - Sen Lin
- Department of Chemistry
- Nanchang University
- Nanchang
- P. R. China
| | - Xiaoqing You
- Department of Chemistry
- Nanchang University
- Nanchang
- P. R. China
| | - Yao Yang
- Department of Chemistry
- Nanchang University
- Nanchang
- P. R. China
| | - Zhaohua Yan
- Department of Chemistry
- Nanchang University
- Nanchang
- P. R. China
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19
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Luo K, Yang WC, Wei K, Liu Y, Wang JK, Wu L. Di-tert-butyl Peroxide-Mediated Radical C(sp2/sp3)–S Bond Cleavage and Group-Transfer Cyclization. Org Lett 2019; 21:7851-7856. [DOI: 10.1021/acs.orglett.9b02837] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Kai Luo
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Wen-Chao Yang
- Institute of Pesticide, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Kai Wei
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Yue Liu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jun-Ke Wang
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lei Wu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
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20
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Paul B, Panja D, Kundu S. Ruthenium-Catalyzed Synthesis of N-Methylated Amides using Methanol. Org Lett 2019; 21:5843-5847. [DOI: 10.1021/acs.orglett.9b01925] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bhaskar Paul
- Department of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Dibyajyoti Panja
- Department of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Sabuj Kundu
- Department of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
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21
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Lv W, Wen S, Liu J, Cheng G. Palladium-Catalyzed ortho-C–H Methylation of Benzoic Acids. J Org Chem 2019; 84:9786-9791. [DOI: 10.1021/acs.joc.9b01204] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Weiwei Lv
- College of Materials Science & Engineering, Huaqiao University, Xiamen 361021, China
| | - Si Wen
- College of Materials Science & Engineering, Huaqiao University, Xiamen 361021, China
| | - Jing Liu
- College of Materials Science & Engineering, Huaqiao University, Xiamen 361021, China
| | - Guolin Cheng
- College of Materials Science & Engineering, Huaqiao University, Xiamen 361021, China
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22
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Patel OPS, Nandwana NK, Sah AK, Kumar A. Metal-free synthesis of aminomethylated imidazoheterocycles: dual role of tert-butyl hydroperoxide as both an oxidant and a methylene source. Org Biomol Chem 2019; 16:8620-8628. [PMID: 30379182 DOI: 10.1039/c8ob02432d] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A novel and efficient aminomethylation approach has been developed for the regioselective functionalization of imidazoheterocycles under metal-free conditions. A wide range of imidazoheterocycles and 2/4-aminoazaheterocycles successfully provided corresponding aminomethylated imidazoheterocycles in moderate to excellent (33-80%) yields. The isotopic labelling study suggested that TBHP played a dual role as both an oxidant and a methylene source in this transformation. The developed protocol follows a radical pathway which is supported by radical trapping experiments.
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Affiliation(s)
- Om P S Patel
- Department of Chemistry, Birla Institute of Technology and Science Pilani, Pilani Campus, 333031, Rajasthan, India.
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23
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Li ZL, Sun KK, Cai C. Nickel-catalyzed regioselective C–H oxygenation: new routes for versatile C–O bond formation. Org Chem Front 2019. [DOI: 10.1039/c8qo01274a] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Nickel-catalyzed regioselective C–H oxygenation reactions of chelating arenes using iodobenzene diacetate, alcohols, and benzoic acids respectively as attacking reagents have been developed for the first time.
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Affiliation(s)
- Ze-lin Li
- College of Chemical Engineering
- Nanjing University of Science & Technology
- Nanjing
- China
| | - Kang-kang Sun
- College of Chemical Engineering
- Nanjing University of Science & Technology
- Nanjing
- China
| | - Chun Cai
- College of Chemical Engineering
- Nanjing University of Science & Technology
- Nanjing
- China
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24
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Chen Y. Recent Advances in Methylation: A Guide for Selecting Methylation Reagents. Chemistry 2018; 25:3405-3439. [DOI: 10.1002/chem.201803642] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Yantao Chen
- Medicinal Chemistry, Cardiovascular, Renal and Metabolism, IMED Biotech UnitAstraZeneca Gothenburg Sweden
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25
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Li ZL, Sun KK, Cai C. Nickel-Catalyzed Cross-Dehydrogenative Coupling of α-C(sp 3)-H Bonds in N-Methylamides with C(sp 3)-H Bonds in Cyclic Alkanes. Org Lett 2018; 20:6420-6424. [PMID: 30272983 DOI: 10.1021/acs.orglett.8b02736] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A nickel-catalyzed cross-dehydrogenative coupling reaction of α-C(sp3)-H bonds in N-methylamides with C(sp3)-H bonds from cyclic alkanes has been developed, which offers a cheap transition-metal-catalyzed C-H activation method for amides without the requirement for any extraneous directing group. This new strategy is highly selective and tolerates a variety of functional groups. Mechanistic investigations into the reaction process are also described in detail.
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Affiliation(s)
- Ze-Lin Li
- Chemical Engineering College , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China
| | - Kang-Kang Sun
- Chemical Engineering College , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China
| | - Chun Cai
- Chemical Engineering College , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China.,Key Laboratory of Organofluorine Chemistry , Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 20032 , People's Republic of China
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26
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Yu L, Qian R, Deng X, Wang F, Xu Q. Calcium-catalyzed reactions of element-H bonds. Sci Bull (Beijing) 2018; 63:1010-1016. [PMID: 36658887 DOI: 10.1016/j.scib.2018.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/27/2018] [Accepted: 05/28/2018] [Indexed: 01/21/2023]
Abstract
Investigation on organocalcium catalysis is just unfolding during the past decade. Beside conventional Ca salts with strong electron-withdrawing counter anions that may serve as Lewis acid catalysts, many Ca complexes have also been designed recently and found to be good catalysts in activation of element-H (EH) bonds like transition metal catalysts. These findings are interesting and may attract the interest of the chemists. Due to the great abundance, non-toxicity, and biocompatible features of Ca element, Ca-catalyzed reactions can be of great significance from the viewpoint of industry. This short review summarizes the recent advances on Ca-catalyzed reactions of EH bonds. We hope that it may provide a useful guide for interested readers from both the academy and industry.
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Affiliation(s)
- Lei Yu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
| | | | - Xin Deng
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
| | - Fang Wang
- Yangzhou Polytechnology Institute, Yangzhou 225127, China
| | - Qing Xu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China
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