1
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Singh V, Rajput K, Mishra A, Singh S, Srivastava V. Microwave-assisted chemoselective transamidation of secondary amides by selective N-C(O) bond cleavage under catalyst, additive and solvent-free conditions. Chem Commun (Camb) 2023; 59:14009-14012. [PMID: 37941417 DOI: 10.1039/d3cc04128j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
A microwave-assisted, highly chemoselective protocol has been developed for the transamidation of tert-butyloxycarbonyl (Boc) activated secondary carboxamides with amines. Under non-conventional microwave techniques, the reactions were achieved under catalyst, additive, promoter and solvent-free conditions. The transamidation of a structurally diverse set of amides and amines was accomplished in good to excellent yields. The salient features of the developed methodology include a simple operation, broad substrate scope, functional group tolerance, practicality, and the scalability.
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Affiliation(s)
- Vishal Singh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi-221005, UP, India.
| | - Khushbu Rajput
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi-221005, UP, India.
| | - Ankush Mishra
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi-221005, UP, India.
| | - Sundaram Singh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi-221005, UP, India.
| | - Vandana Srivastava
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi-221005, UP, India.
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2
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Zhao M, Chen M, Wang T, Yang S, Peng Q, Tang P. Fluorocarbonylation via palladium/phosphine synergistic catalysis. Nat Commun 2023; 14:4583. [PMID: 37524725 PMCID: PMC10390470 DOI: 10.1038/s41467-023-40180-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 07/13/2023] [Indexed: 08/02/2023] Open
Abstract
Despite the growing importance of fluorinated organic compounds in pharmaceuticals, agrochemicals, and materials science, the introduction of fluorine into organic molecules is still a challenge, and no catalytic fluorocarbonylation of aryl/alkyl boron compounds has been reported to date. Herein, we present the development of palladium and phosphine synergistic redox catalysis of fluorocarbonylation of potassium aryl/alkyl trifluoroborate. Trifluoromethyl arylsulfonate (TFMS), which was used as a trifluoromethoxylation reagent, an easily handled and bench-scale reagent, has been employed as an efficient source of COF2. The reaction operates under mild conditions with good to excellent yields and tolerates diverse complex scaffolds, which allows efficient late-stage fluorocarbonylation of marked small-molecule drugs. Mechanistically, the key intermediates of labile Brettphos-Pd(II)-OCF3 complex and difluoro-Brettphos were synthesized and spectroscopically characterized, including X-ray crystallography. A detailed reaction mechanism involving the synergistic redox catalytic cycles Pd(II)/(0) and P(III)/(V) was proposed, and multifunction of phosphine ligand was identified based on 19F NMR, isotope tracing, synthetic, and computational studies.
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Affiliation(s)
- Mingxin Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Miao Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Tian Wang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Shuhan Yang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Qian Peng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China.
- Haihe Laboratory of Sustainable Chemical Transformations, 300192, Tianjin, China.
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China.
- Haihe Laboratory of Sustainable Chemical Transformations, 300192, Tianjin, China.
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3
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Jia J, Kato T, Maruoka K. p-Methoxybenzyl-Radical-Promoted Chemoselective Protection of sec-Alkylamides. J Org Chem 2023; 88:2575-2582. [PMID: 36731133 DOI: 10.1021/acs.joc.2c02582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The hitherto difficult site-selective p-methoxybenzylation of secondary amides using p-methoxybenzylated alkylsilyl peroxides as a novel p-methoxybenzylation agent under copper catalysis is reported. The reaction proceeds under mild reaction conditions in a highly chemoselective manner. This approach was successfully applied to the site-selective p-methoxybenzylation of peptides.
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Affiliation(s)
- JingWen Jia
- Laboratory of Organocatalytic Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Terumasa Kato
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
| | - Keiji Maruoka
- Laboratory of Organocatalytic Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan.,School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
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4
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Zhang ZH, Zhou Q, Li Z, Zhang N, Zhang L. Completely stereospecific synthesis of a molecular cinquefoil (51) knot. Chem 2022. [DOI: 10.1016/j.chempr.2022.11.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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5
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Lee HJ, Choi ES, Maruoka K. Development of a catalytic ester activation protocol for the efficient formation of amide bonds using an Ar‐I/HF•pyridine/mCPBA system. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202200483] [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)
- Hyo-Jun Lee
- Kunsan National University Department of Chemistry KOREA, REPUBLIC OF
| | - Eun-Sol Choi
- Kunsan National University Department of Chemistry KOREA, REPUBLIC OF
| | - Keiji Maruoka
- Kyoto University Graduate School of Pharmaceutical Sciences Sakyo 606-8501 Kyoto JAPAN
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6
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Yu WL, Ren ZG, Ma KX, Yang HQ, Yang JJ, Zheng H, Wu W, Xu PF. Cobalt-catalyzed chemoselective dehydrogenation through radical translocation under visible light. Chem Sci 2022; 13:7947-7954. [PMID: 35865906 PMCID: PMC9258329 DOI: 10.1039/d2sc02291e] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 06/13/2022] [Indexed: 11/21/2022] Open
Abstract
The transformations that allow the direct removal of hydrogen from their corresponding saturated counterparts by the dehydrogenative strategy are a dream reaction that has remained largely underexplored. In this report, a straightforward and robust cobaloxime-catalyzed photochemical dehydrogenation strategy via intramolecular HAT is described for the first time. The reaction proceeds through an intramolecular radical translocation followed by the cobalt assisted dehydrogenation without needing any other external photosensitizers, noble-metals or oxidants. With this approach, a series of valuable unsaturated compounds such as α,β-unsaturated amides, enamides and allylic and homoallylic sulfonamides were obtained in moderate to excellent yields with good chemo- and regioselectivities, and the synthetic versatility was demonstrated by a range of transformations. And mechanistic studies of the method are discussed. The dehydrogenative reactions proceeded through selective 1,n-hydrogen atom transfer (n = 5–7) for remote C–H activation by cobaloxime catalysis.![]()
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Affiliation(s)
- Wan-Lei Yu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China .,Frontiers Science Center for Rare Isotopes, Lanzhou University Lanzhou China
| | - Zi-Gang Ren
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Ke-Xing Ma
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Hui-Qing Yang
- Henan and Macquarie University Joint Centre for Biomedical Innovation, School of Life Sciences, Henan University Kaifeng 475004 China
| | - Jun-Jie Yang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Haixue Zheng
- State Key Laboratory of Veterinary Etiological Biology, College of Veterinary Medicine, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences Lanzhou China
| | - Wangsuo Wu
- Frontiers Science Center for Rare Isotopes, Lanzhou University Lanzhou China
| | - Peng-Fei Xu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China .,State Key Laboratory of Veterinary Etiological Biology, College of Veterinary Medicine, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences Lanzhou China .,Frontiers Science Center for Rare Isotopes, Lanzhou University Lanzhou China
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7
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Nishihara Y, Tian T, Chen Q, Li Z. Recent Advances in C–F Bond Activation of Acyl Fluorides Directed toward Catalytic Transformation by Transition Metals, N-Heterocyclic Carbenes, or Phosphines. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/a-1845-3810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AbstractNumerous studies on the activation of carbon–fluorine bonds have been reported in recent years. For example, acyl fluorides have been utilized as versatile reagents for acylation, arylation, and even fluorination. In this review, we focus on acyl fluorides as compounds with carbon–fluorine bonds, and highlight recent advances in strategies for the activation of their C–F bonds via transition-metal catalysis, N-heterocyclic carbene (NHCs) catalysis, organophosphine catalysis, and classical nucleophilic substitution reactions.1 Introduction2 Transition-Metal-Mediated C–F Bond Activation2.1 Acylation (Carbonyl-Retentive) Coupling Reactions2.2 Decarbonylative Reactions2.3 C–F Bond Activation by Other Transition Metals3 C–F Bond Activation by N-Heterocyclic Carbenes (NHCs)3.1 NHC-Catalyzed Cycloaddition of Acyl Fluorides3.2 NHC-Catalyzed Radical Functionalization of Acyl Fluorides3.3 NHC-Catalyzed Nucleophilic Fluorination of (Hetero)aromatics4 C–F Bond Activation by Phosphines4.1 Phosphine-Catalyzed Direct Activation of the C–F Bond of Acyl Fluorides4.2 Phosphine-Catalyzed Indirect Activation of the C–F Bond of Acyl Fluorides5 C–F Bond Activation by Classical Nucleophilic Substitution6 Miscellaneous Examples7 Summary and Perspective
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Affiliation(s)
- Yasushi Nishihara
- Research Institute for Interdisciplinary Science, Okayama University
| | - Tian Tian
- Graduate School of Natural Science and Technology, Okayama University
| | - Qiang Chen
- Graduate School of Natural Science and Technology, Okayama University
| | - Zhiping Li
- Department of Chemistry, Renmin University of China
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8
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Aliyu Idris M, Song KH, Lee S. Synthesis of (Hetero)Aroyl Fluorides via a Mild Amides C−N Bond Cleavage. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Muhammad Aliyu Idris
- Department of Chemistry Chonnam National University Gwangju 61186 Republic of Korea
| | - Kwang Ho Song
- Department of Chemical & Biological Engineering Korea University Seoul 02841 Republic of Korea
| | - Sunwoo Lee
- Department of Chemistry Chonnam National University Gwangju 61186 Republic of Korea
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9
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Zuo D, Wang Q, Liu L, Huang T, Szostak M, Chen T. Highly Chemoselective Transamidation of Unactivated Tertiary Amides by Electrophilic N-C(O) Activation by Amide-to-Acyl Iodide Re-routing. Angew Chem Int Ed Engl 2022; 61:e202202794. [PMID: 35355386 DOI: 10.1002/anie.202202794] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Indexed: 12/20/2022]
Abstract
The challenging transamidation of unactivated tertiary amides has been accomplished via cooperative acid/iodide catalysis. Most crucially, the method provides a novel manifold to re-route the reactivity of unactivated N,N-dialkyl amides through reactive acyl iodide intermediates, thus reverting the classical order of reactivity of carboxylic acid derivatives. This method provides a direct route to amide-to-amide bond interconversion with excellent chemoselectivity using equivalent amounts of amines. The combination of acid and iodide has been identified as the essential factor to activate the amide C-N bond through electrophilic catalytic activation, enabling the production of new desired transamidated products with wide substrate scope of both unactivated amides and amines, including late-stage functionalization of complex APIs (>80 examples). We anticipate that this powerful activation mode of unactivated amide bonds will find broad-ranging applications in chemical synthesis.
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Affiliation(s)
- Dongxu Zuo
- College of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
| | - Qun Wang
- College of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Long Liu
- College of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
| | - Tianzeng Huang
- College of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Tieqiao Chen
- College of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
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10
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Wu FW, Mao YJ, Pu J, Li HL, Ye P, Xu ZY, Lou SJ, Xu DQ. Ni-catalysed deamidative fluorination of amides with electrophilic fluorinating reagents. Org Biomol Chem 2022; 20:4091-4095. [PMID: 35522070 DOI: 10.1039/d2ob00519k] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We describe here a Ni-catalysed deamidative fluorination of diverse amides with electrophilic fluorinating reagents. Different types of amides including aromatic amides and olefinic amides were well compatible, affording the corresponding acyl fluorides in good to excellent yields.
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Affiliation(s)
- Feng-Wei Wu
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Yang-Jie Mao
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Jun Pu
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Huan-Le Li
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Peng Ye
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Zhen-Yuan Xu
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Shao-Jie Lou
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Dan-Qian Xu
- Catalytic Hydrogenation Research Center, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Key Laboratory of Green Pesticides and Cleaner Production Technology of Zhejiang Province, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
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11
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Zuo D, Wang Q, Liu L, Huang T, Szostak M, Chen T. Highly Chemoselective Transamidation of Unactivated Tertiary Amides by Electrophilic N–C(O) Activation via Amide‐to‐Acyl Iodide Re‐Routing. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dongxu Zuo
- Hainan University College of Chemical Engineering and Technology CHINA
| | - Qun Wang
- Hunan University College of Chemistry and Chemical Engineering CHINA
| | - Long Liu
- Hainan University College of Chemical Engineering and Technology CHINA
| | - Tianzeng Huang
- Hainan University College of Chemical Engineering and Technology CHINA
| | - Michal Szostak
- Rutgers University Newark Department of Chemistry UNITED STATES
| | - Tieqiao Chen
- Hainan University College of Chemical Engineering and Technology No. 58, Renmin Avenue, Meilan District 570228 Haikou CHINA
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12
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Lai H, Xu J, Lin J, Su B, Zha D. Chemo-selective control of Ritter-type reaction by coordinatively unsaturated inorganic salt hydrates. Org Chem Front 2022. [DOI: 10.1039/d1qo01832a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We used a readily available water source, MgSO4·2H2O, to realize the control of the chemo-selectivity of the Ritter-type reaction efficiently.
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Affiliation(s)
- Huifang Lai
- Department of Medicinal Chemistry, School of Pharmacy, Fujian Medical University, Fuzhou 350004, Fujian Province, China
| | - Jiexin Xu
- Department of Medicinal Chemistry, School of Pharmacy, Fujian Medical University, Fuzhou 350004, Fujian Province, China
| | - Jin Lin
- Department of Medicinal Chemistry, School of Pharmacy, Fujian Medical University, Fuzhou 350004, Fujian Province, China
| | - Biling Su
- Department of Medicinal Chemistry, School of Pharmacy, Fujian Medical University, Fuzhou 350004, Fujian Province, China
| | - Daijun Zha
- Department of Medicinal Chemistry, School of Pharmacy, Fujian Medical University, Fuzhou 350004, Fujian Province, China
- Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, Fujian Medical University, China
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13
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Kumar V, Dhawan S, Girase PS, Singh P, Karpoormath R. An Environmentally Benign, Catalyst‐Free N−C Bond Cleavage/Formation of Primary, Secondary, and Tertiary Unactivated Amides. European J Org Chem 2021. [DOI: 10.1002/ejoc.202101114] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Vishal Kumar
- Department of Pharmaceutical Chemistry Discipline of Pharmaceutical Sciences College of Health Sciences University of KwaZulu-Natal (Westville) Durban 4000 South Africa
| | - Sanjeev Dhawan
- Department of Pharmaceutical Chemistry Discipline of Pharmaceutical Sciences College of Health Sciences University of KwaZulu-Natal (Westville) Durban 4000 South Africa
| | - Pankaj Sanjay Girase
- Department of Pharmaceutical Chemistry Discipline of Pharmaceutical Sciences College of Health Sciences University of KwaZulu-Natal (Westville) Durban 4000 South Africa
| | - Parvesh Singh
- School of Chemistry and Physics University of KwaZulu-Natal P/Bag X54001, Westville Durban 4000 South Africa
| | - Rajshekhar Karpoormath
- Department of Pharmaceutical Chemistry Discipline of Pharmaceutical Sciences College of Health Sciences University of KwaZulu-Natal (Westville) Durban 4000 South Africa
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14
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Fung AKK, Yu LJ, Sherburn MS, Coote ML. Atom Transfer Radical Polymerization-Inspired Room Temperature (sp 3)C-N Coupling. J Org Chem 2021; 86:9723-9732. [PMID: 34181425 DOI: 10.1021/acs.joc.1c01029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A simple nonphotochemical procedure is reported for Cu(I)-catalyzed C-N coupling of aliphatic halides with amines and amides. The process is loosely based on the Goldberg reaction but takes place readily at room temperature. It uses Cu(I)Br, a commonly used and inexpensive atom transfer radical polymerization precatalyst, along with the cheap ligand N,N,N',N″,N″-pentamethyldiethylenetriamine, to activate the R-X bond of the substrate via inner-sphere electron transfer. The procedure brings about productive C-N bond formation between a range of alkyl halide substrates with heterocyclic aromatic amines and amides. The mechanism of the coupling step, which was elucidated through application of computational methods, proceeds via a unique Cu(I) → Cu(II) → Cu(III) → Cu(I) catalytic cycle, involving (a) inner-sphere electron transfer from Cu(I) to the alkyl halide to generate the alkyl radical; (b) successive coordination of the N-nucleophile and the radical to Cu(II); and finally reductive elimination. In the absence of a nucleophile, debrominative homocoupling of the alkyl halide occurs. Control experiments rule out SN-type mechanisms for C-N bond formation.
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Affiliation(s)
- Alfred K K Fung
- ARC Centre of Excellence for Electromaterials Science, Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Li-Juan Yu
- ARC Centre of Excellence for Electromaterials Science, Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Michael S Sherburn
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Michelle L Coote
- ARC Centre of Excellence for Electromaterials Science, Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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15
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Matsumoto A, Wang Z, Maruoka K. Radical-Mediated Activation of Esters with a Copper/Selectfluor System: Synthesis of Bulky Amides and Peptides. J Org Chem 2021; 86:5401-5411. [PMID: 33720721 DOI: 10.1021/acs.joc.1c00188] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, we describe a new approach for the activation of esters via a radical-mediated process enabled by a copper/Selectfluor system. A variety of para-methoxybenzyl esters derived from bulky carboxylic acids and amino acids can be easily converted into the corresponding acyl fluorides, directly used in the one-pot synthesis of amides and peptides. As a proof of concept, this method was applied to the iterative formation of sterically hindered amide bonds.
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Affiliation(s)
- Akira Matsumoto
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Zhe Wang
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Keiji Maruoka
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan.,School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
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