1
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Konowalchuk DJ, Clement HA, Lofstrand VA, Kim JY, Burford KN. Diastereoselective Hydrodifluoromethylation of Alkenyl N-Heterocycles via Photocatalytic Radical-Polar Crossover. J Org Chem 2024. [PMID: 39397589 DOI: 10.1021/acs.joc.4c02169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2024]
Abstract
A diastereoselective hydrodifluoromethylation of N-heteroaryl alkenes was successfully established. This method was applicable to an array of N-heteroaryl substrates with both cyclic and acyclic alkenes while displaying tolerance to a variety of functional groups. The conditions were also expanded to obtain hydrotrifluoromethylated products with similar results. Initial mechanistic studies suggest that the final protonation step is accessed through a radical-polar crossover process.
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Affiliation(s)
- Dawson J Konowalchuk
- Xenon Pharmaceuticals Inc., 3650 Gilmore Way, Burnaby, British Columbia, Canada, V5G 4W8
| | - Helen A Clement
- Xenon Pharmaceuticals Inc., 3650 Gilmore Way, Burnaby, British Columbia, Canada, V5G 4W8
| | - Verner A Lofstrand
- Xenon Pharmaceuticals Inc., 3650 Gilmore Way, Burnaby, British Columbia, Canada, V5G 4W8
| | - Jung Y Kim
- Xenon Pharmaceuticals Inc., 3650 Gilmore Way, Burnaby, British Columbia, Canada, V5G 4W8
| | - Kristen N Burford
- Xenon Pharmaceuticals Inc., 3650 Gilmore Way, Burnaby, British Columbia, Canada, V5G 4W8
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2
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Zhang D, Sun Y, Wang G, Liu Y, Ni C, Ji Q, Xu X, Fang Z. Preparation of Difluoromethylated Benzothiophene by Visible-Light-Mediated Alkyne Difunctionalization Reaction. J Org Chem 2024; 89:13367-13372. [PMID: 39240042 DOI: 10.1021/acs.joc.4c01528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2024]
Abstract
An efficient method for the preparation of difluoromethylated benzothiophenes via visible-light-mediated alkyne difunctionalization was developed. In this method, inexpensive sodium difluoromethanesulfinate (HCF2SO2Na) was used as the fluorine source, and a variety of benzothiophene derivatives were obtained in moderate to excellent yield under mild reaction conditions. Moreover, the reaction operation is simple and easy to scale up.
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Affiliation(s)
- Dong Zhang
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Yu Sun
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Ganwen Wang
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Ying Liu
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Chunjie Ni
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Qingzhi Ji
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Xiaojuan Xu
- School of Pharmacy, Yancheng Teachers University, Yancheng 224007, China
| | - Zheng Fang
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China
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3
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Mizuta S, Yamaguchi T, Iwasaki M, Ishikawa T. A facile access to aliphatic trifluoromethyl ketones via photocatalyzed cross-coupling of bromotrifluoroacetone and alkenes. Org Biomol Chem 2024. [PMID: 39258408 DOI: 10.1039/d4ob01247j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2024]
Abstract
Biological molecules incorporating trifluoromethyl ketones (TFMKs) have emerged as reversible covalent inhibitors, aiding in the management and treatment of inflammatory diseases, cancer, and respiratory conditions. TFMKs, renowned for their versatile binding properties and adaptability, are pivotal in the rational design of novel drugs for diverse diseases. The photocatalytic insertion of alkenes, abundant feedstocks, into the α-carbon of trifluoromethylacetone represents a highly effective and atom-economical method for synthesizing valuable TFMKs. However, these processes typically necessitate high-energy photoirradiation (λ > 300 nm, Hg lamp) and stoichiometric oxidants to generate the acetonyl radical from acetone. In our study, we demonstrate the visible-light photocatalytic radical addition into olefins using bromotrifluoroacetone as the trifluoroacetonyl radical precursor under mild conditions. Aliphatic trifluoromethyl ketones or the corresponding bromo-substituted products can be obtained by selecting an appropriate photocatalyst and solvent. Comprehensive experimental investigations, including cyclic voltammetry, Stern-Volmer quenching studies, and kinetic isotope effects, corroborate the synthesis of trifluoroacetonyl radical species from bromotrifluoroacetone under photoredox conditions. Further, we demonstrate the efficient synthesis of an oseltamivir derivative bearing a trifluoromethylketone moiety, which shows promising biological activity. Hence, this methodology will streamline the direct introduction of trifluoromethyl ketone into biological target molecules during drug discovery.
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Affiliation(s)
- Satoshi Mizuta
- Center for Bioinformatics and Molecular Medicine, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo, Nagasaki, 852-8521, Japan.
| | - Tomoko Yamaguchi
- Center for Bioinformatics and Molecular Medicine, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo, Nagasaki, 852-8521, Japan.
| | - Masaharu Iwasaki
- Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
- Center for Advanced Modalities and Drug Delivery System, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
- RNA Frontier Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Osaka, Japan
| | - Takeshi Ishikawa
- Department of Chemistry, Biotechnology, and Chemical Engineering, Graduate School of Science and Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890-0065, Japan.
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4
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Liu J, Cui Z, Bi J, He X, Ding Q, Zhu H, Ma C. Photocatalytic fluoroalkylation by ligand-to-metal charge transfer. Front Chem 2024; 12:1481342. [PMID: 39308850 PMCID: PMC11412811 DOI: 10.3389/fchem.2024.1481342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2024] [Accepted: 08/27/2024] [Indexed: 09/25/2024] Open
Abstract
Trifluoromethyl (CF3) and other fluoroalkyl groups are of great significance in the fields of pharmaceutical chemistry and agricultural chemicals. Fluoroalkyl acids, especially trifluoroacetic acid (TFA) is considered the most ideal fluoroalkylation reagent due to its low cost and easy availability. However, the extremely high oxidation potential requirement of TFA limits its wide application. In recent years, since visible-light-induced fluoroalkylation through the ligand-to-metal charge transfer (LMCT) process can overcome the above limitations, it has become an effective synthetic tool for the construction of fluorinated compounds with complex molecules and structures. In this review, according to the classification of different metal catalysts, we summarize the trifluoromethylation and fluoroalkylation of olefins, heteroaromatics, and terminal alkynes in different metal catalytic systems and their corresponding reaction mechanisms. The photocatalytic fluoroalkylation via LMCT is believed to expedite the development of fluoro-containing drugs, and more novel fluoroalkylation methologies using this strategy will be disclosed.
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Affiliation(s)
- Jingyi Liu
- Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Henan Engineering Research Centre of Chiral Hydroxyl Pharmaceutical, Henan Engineering Laboratory of Chemical Pharmaceutical and Biomedical Materials, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
| | - Zhenwei Cui
- Chongqing Aoshe Bio-Chemical Co., Ltd., Chongqing, China
| | - Jingjing Bi
- School of Pharmacy, Xinyang Agricultural and Forestry University, Xinyang, Henan, China
| | - Xing He
- Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Henan Engineering Research Centre of Chiral Hydroxyl Pharmaceutical, Henan Engineering Laboratory of Chemical Pharmaceutical and Biomedical Materials, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
| | - Qingjie Ding
- Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Henan Engineering Research Centre of Chiral Hydroxyl Pharmaceutical, Henan Engineering Laboratory of Chemical Pharmaceutical and Biomedical Materials, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
| | - Hong Zhu
- Anesthesiology and Perioperative, Xinxiang Central Hospital, Xinxiang, China
| | - Chunhua Ma
- Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Henan Engineering Research Centre of Chiral Hydroxyl Pharmaceutical, Henan Engineering Laboratory of Chemical Pharmaceutical and Biomedical Materials, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
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5
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He XB, Jia X, Zhao PQ, Fang Z, Qing FL. Photoredox-Catalysis Fluorosulfonyldifluoromethylation of Unactivated Alkenes and (Hetero)arenes with ICF 2SO 2F. Org Lett 2024; 26:6900-6904. [PMID: 39115249 DOI: 10.1021/acs.orglett.4c02538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
The fluorosulfonyldifluoromethylation of unactivated alkenes and (hetero)arenes with iododifluoromethanesulfonyl fluoride (ICF2SO2F) under visible light photoredox catalysis was successfully developed. Key to the successful fluorosulfonyldifluoromethylation of aromatic compounds was the usage of AgOTf as an additive to promote the formation of the CF2SO2F radical. The protocol provided a straightforward way to introduce the interesting and useful CF2SO2F group on sp3 and sp2 carbons.
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Affiliation(s)
- Xu-Biao He
- Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Xin Jia
- Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Pin-Qiao Zhao
- Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zeguo Fang
- New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base, Hubei University of Technology, Wuhan 430068, China
| | - Feng-Ling Qing
- Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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6
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Kim S, Kim H. Cu-Electrocatalysis Enables Vicinal Bis(difluoromethylation) of Alkenes: Unraveling Dichotomous Role of Zn(CF 2H) 2(DMPU) 2 as Both Radical and Anion Source. J Am Chem Soc 2024; 146:22498-22508. [PMID: 39079933 DOI: 10.1021/jacs.4c06207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
The difluoromethyl group (CF2H) serves as an essential bioisostere in drug discovery campaigns according to Lipinski's Rule of 5 due to its advantageous combination of lipophilicity and hydrogen bonding ability, thereby improving the ADME properties. However, despite the high prevalence and importance of vicinal hydrogen bond donors in pharmaceutical agents, a general synthetic method for doubly difluoromethylated compounds in the vicinal position is absent. Here we describe a copper-electrocatalyzed strategy that enables the vicinal bis(difluoromethylation) of alkenes. By leveraging electrochemistry to oxidize Zn(CF2H)2(DMPU)2-a conventionally utilized anionic transmetalating source, we paved a way to utilize it as a CF2H radical source to deliver the CF2H group in the terminal position of alkenes. Mechanistic studies revealed that the interception of the resultant secondary radical by a copper catalyst and subsequent reductive elimination is facilitated by invoking the Cu(III) intermediate, enabling the second installation of the CF2H group in the internal position. The utility of this electrocatalytic 1,2-bis(difluoromethylation) strategy has been highlighted through the late-stage bioisosteric replacement of pharmaceutical agents such as sotalol and dipivefrine.
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Affiliation(s)
- Seonyoung Kim
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Hyunwoo Kim
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University, Seoul 03722, Republic of Korea
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7
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Lin SN, Deng Y, Zhong H, Mao LL, Ji CB, Zhu XH, Zhang X, Yang BM. Visible Light-Induced Radical Cascade Difluoromethylation/Cyclization of Unactivated Alkenes: Access to CF 2H-Substituted Polycyclic Imidazoles. ACS OMEGA 2024; 9:28129-28143. [PMID: 38973879 PMCID: PMC11223139 DOI: 10.1021/acsomega.4c01177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 06/07/2024] [Accepted: 06/11/2024] [Indexed: 07/09/2024]
Abstract
An efficient and mild protocol for the visible light-induced radical cascade difluoromethylation/cyclization of imidazoles with unactivated alkenes using easily accessible and bench-stable difluoromethyltriphenylphosphonium bromide as the precursor of the -CF2H group has been developed to afford CF2H-substituted polycyclic imidazoles in moderate to good yields. This strategy, along with the construction of Csp3-CF2H/C-C bonds, is distinguished by mild conditions, no requirement of additives, simple operation, and wide substrate scope. In addition, the mechanistic experiments have indicated that the difluoromethyl radical pathway is essential for the methodology.
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Affiliation(s)
- Sheng-Nan Lin
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Yuanyuan Deng
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Hanxun Zhong
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Liu-Liang Mao
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Cong-Bin Ji
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Xian-Hong Zhu
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Xiaolan Zhang
- College
of Chemistry and Environment Science, Shangrao
Normal University, Shangrao 334001, China
| | - Bin-Miao Yang
- Joint
School of National University of Singapore and Tianjin University, Fuzhou 350207, China
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8
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Ford J, Ortalli S, Gouverneur V. The 18F-Difluoromethyl Group: Challenges, Impact and Outlook. Angew Chem Int Ed Engl 2024; 63:e202404957. [PMID: 38640422 DOI: 10.1002/anie.202404957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/18/2024] [Accepted: 04/19/2024] [Indexed: 04/21/2024]
Abstract
The difluoromethyl functionality has proven useful in drug discovery, as it can modulate the properties of bioactive molecules. For PET imaging, this structural motif has been largely underexploited in (pre)clinical radiotracers due to a lack of user-friendly radiosynthetic routes. This Minireview provides an overview of the challenges facing radiochemists and summarises the efforts made to date to access 18F-difluoromethyl-containing radiotracers. Two distinct approaches have prevailed, the first of which relies on 18F-fluorination. A second approach consists of a 18F-difluoromethylation process, which uses 18F-labelled reagents capable of releasing key reactive intermediates such as the [18F]CF2H radical or [18F]difluorocarbene. Finally, we provide an outlook for future directions in the radiosynthesis of [18F]CF2H compounds and their application in tracer radiosynthesis.
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Affiliation(s)
- Joseph Ford
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Sebastiano Ortalli
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Véronique Gouverneur
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
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9
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Zhu X, Zhang M, Shen L, Su W. Visible-Light-Induced Hydrodifluoromethylation of Unactivated Alkenes with Difluoroacetic Anhydride. J Org Chem 2024; 89:8828-8835. [PMID: 38848324 DOI: 10.1021/acs.joc.4c00702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2024]
Abstract
We herein described a practical and efficient protocol for hydrodifluoromethylation of unactivated alkenes using readily available difluoroacetic anhydride as a difluoromethyl source by merging photocatalysis and N-hydroxyphthalimide activation. This method features a wide substrate scope and excellent compatibility with various functional groups, as demonstrated by more than 50 examples, including bioactive molecules and pharmaceutical derivatives. Mechanism investigation indicated that N-hydroxyphthalimide may also serve as the hydrogen atom donor.
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Affiliation(s)
- Xiaoliang Zhu
- College of Chemistry, Fuzhou University, Fuzhou 350108, China
- State Key Laboratory of Structural Chemistry, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
| | - Min Zhang
- College of Chemistry, Fuzhou University, Fuzhou 350108, China
- State Key Laboratory of Structural Chemistry, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
| | - Lujie Shen
- College of Chemistry, Fuzhou University, Fuzhou 350108, China
- State Key Laboratory of Structural Chemistry, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
| | - Weiping Su
- College of Chemistry, Fuzhou University, Fuzhou 350108, China
- State Key Laboratory of Structural Chemistry, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
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10
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Wang Y, Liu S, Huang Y. Photoredox/copper-catalyzed gem-difluoroalkylation-cyanation of 1,3-enynes. Org Biomol Chem 2024; 22:4895-4900. [PMID: 38826121 DOI: 10.1039/d4ob00602j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
A photoredox/copper-catalyzed 1,4-difunctionalization of 1,3-enynes with readily available difluoroalkylating reagents and TMSCN was developed. This reaction proceeded at mild conditions, affording the corresponding difluoroalkylated allenes in good yields with high functional-group tolerance and excellent regioselectivity.
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Affiliation(s)
- Yachen Wang
- College of Chemistry and Chemical Engineering, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China.
| | - Shuai Liu
- National Engineering Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang, 330022, China.
| | - Yangen Huang
- College of Chemistry and Chemical Engineering, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China.
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11
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Li S, Wei W, Chi K, Ferguson CTJ, Zhao Y, Zhang KAI. Promoting Photocatalytic Direct C-H Difluoromethylation of Heterocycles using Synergistic Dual-Active-Centered Covalent Organic Frameworks. J Am Chem Soc 2024; 146:12386-12394. [PMID: 38500309 PMCID: PMC11082899 DOI: 10.1021/jacs.3c12880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 03/20/2024]
Abstract
Difluoromethylation reactions are increasingly important for the creation of fluorine-containing heterocycles, which are core groups in a diverse range of biologically and pharmacologically active ingredients. Ideally, this typically challenging reaction could be performed photocatalytically under mild conditions. To achieve this separation of redox processes would be required for the efficient generation of difluoromethyl radicals and the reduction of oxygen. A covalent organic framework photocatalytic material was, therefore, designed with dual reactive centers. Here, anthracene was used as a reduction site and benzothiadiazole was used as an oxidation site, distributed in a tristyryl triazine framework. Efficient charge separation was ensured by the superior electron-donating and -accepting abilities of the dual centers, creating long-lived photogenerated electron-hole pairs. Photocatalytic difluoromethylation of 16 compounds with high yields and remarkable functional group tolerance was demonstrated; compounds included bioactive molecules such as xanthine and uracil. The structure-function relationship of the dual-active-center photocatalyst was investigated through electron spin resonance, femtosecond transient absorption spectroscopy, and density functional theory calculations.
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Affiliation(s)
- Sizhe Li
- Department
of Materials Science, Fudan University, 200433 Shanghai, P. R. China
| | - Wenxin Wei
- Department
of Materials Science, Fudan University, 200433 Shanghai, P. R. China
| | - Kai Chi
- Department
of Materials Science, Fudan University, 200433 Shanghai, P. R. China
| | - Calum T. J. Ferguson
- Max
Planck Institute for Polymer Research, 55128 Mainz, Germany
- School
of Chemistry, University of Birmingham, University Road W, Birmingham B15 2TT, United Kingdom
| | - Yan Zhao
- Department
of Materials Science, Fudan University, 200433 Shanghai, P. R. China
| | - Kai A. I. Zhang
- Department
of Materials Science, Fudan University, 200433 Shanghai, P. R. China
- Max
Planck Institute for Polymer Research, 55128 Mainz, Germany
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12
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Ouyang Y, Qing FL. Photoredox Catalyzed Radical Fluoroalkylation with Non-Classical Fluorinated Reagents. J Org Chem 2024; 89:2815-2824. [PMID: 38385430 DOI: 10.1021/acs.joc.3c02815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
The emergence of photocatalysis has greatly advanced radical fluoroalkylation reactions. Central to this advancement is the introduction and refinement of radical reagents, which play a pivotal role in driving these reactions forward. Intriguingly, some of these reagents, previously not recognized for their radical properties, have emerged as key players in this area. In this Perspective, we provide an overview of four representative reagents pioneered by our laboratory, which have subsequently garnered extensive application in broader research contexts, including difluorocarbene precursors bromodifluoromethylphosphonium bromide, electrophilic sulfonylation reagent triflic anhydride, and nucleophilic trifluoromethylation reagent methyl fluorosulfonyldifluoroacetate (Chen's reagent). The integration of phosphonium reagents, triflic anhydride, and methyl fluorosulfonyldifluoroacetate into photocatalysis has enabled some unexpected reactivities and now notably expanded the capabilities in radical difluoromethylation, trifluoromethylation, and difluoroalkylation. Our discussion highlights how these atypical reagents have enriched the toolkit available for radical fluoroalkylations, offering insights that could inspire future research and application in this area.
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Affiliation(s)
- Yao Ouyang
- Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Feng-Ling Qing
- Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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13
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Zhu Y, Qiu YH, Dai XK, Luo W, Peng X, Chen Z, Yu D. Difluoromethylated Difunctionalization of Alkenes under Visible Light. J Org Chem 2024; 89:2525-2537. [PMID: 38300156 DOI: 10.1021/acs.joc.3c02552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
Difluoromethylated compounds usually act as bioisosteres for alcohol functional groups and show unique physicochemical and biological properties. The cyano-difluoromethylation of alkenes using 5-((difluoromethyl)sulfonyl)-1-phenyl-1H-tetrazole as a CF2H radical difluoromethyl precursor was developed to afford nitriles including a CF2H group. A low-cost, stable, easily handled 5-((difluoromethyl)sulfonyl)-1-methyl-1H-tetrazole (DFSMT) was synthesized and applied as the radical CF2H reagent. Using DFSMT as the radical CF2H precursor, the oxyl-difluoromethylation of alkenes was developed to obtain difluoromethylated ether products. All of the reactions showed good functional group tolerability. Initial mechanistic experiments indicated that the CF2H radical was involved as the key active intermediate.
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Affiliation(s)
- Yuping Zhu
- Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, P. R. China
| | - Yan-Hua Qiu
- Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, P. R. China
| | - Xiao-Kang Dai
- Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, P. R. China
| | - Wenjun Luo
- Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, P. R. China
| | - Xiangjun Peng
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases of Ministry of Education, School of Pharmaceutical Sciences of Gannan Medical University, Ganzhou 341000, P. R. China
| | - Zhengwang Chen
- Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, P. R. China
| | - Daohong Yu
- Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province, Gannan Normal University, Ganzhou 341000, P. R. China
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14
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Xie F, Han F, Yan Y, Li H, Hao J, Jing L, Han P. Difluoromethylation-Carboxylation and -Deuteration of Alkenes Triggered by Electroreduction of Difluoromethyltriphenylphosphonium Bromide. J Org Chem 2023. [PMID: 38056421 DOI: 10.1021/acs.joc.3c02001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
It is significant to develop novel difluoromethylation methods because of the important roles of difluoromethyl groups in the medicinal chemistry and material industries. Here, we developed a novel difluoromethylation-carboxylation and difluoromethylation-deuteration method triggered by a difluoromethyl radical generated by electroreduction of stable and easily available difluoromethyltriphenylphosphonium bromide. Various molecules containing difluoromethyl and carboxyl or deuterium groups can be synthesized through this method. The establishment of this method will provide an alternative to radical difluoromethylation reactions.
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Affiliation(s)
- Fenfen Xie
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
| | - Fen Han
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
| | - Yunying Yan
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
| | - Haiqiong Li
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
| | - Jianjun Hao
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
| | - Linhai Jing
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
| | - Pan Han
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
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15
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Bian KJ, Lu YC, Nemoto D, Kao SC, Chen X, West JG. Photocatalytic hydrofluoroalkylation of alkenes with carboxylic acids. Nat Chem 2023; 15:1683-1692. [PMID: 37957278 PMCID: PMC10983801 DOI: 10.1038/s41557-023-01365-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 10/09/2023] [Indexed: 11/15/2023]
Abstract
Incorporation of fluoroalkyl motifs in pharmaceuticals can enhance the therapeutic profiles of the parent molecules. The hydrofluoroalkylation of alkenes has emerged as a promising route to diverse fluoroalkylated compounds; however, current methods require superstoichiometric oxidants, expensive/oxidative fluoroalkylating reagents and precious metals, and often exhibit limited scope, making a universal protocol that addresses these limitations highly desirable. Here we report the hydrofluoroalkylation of alkenes with cheap, abundant and available fluoroalkyl carboxylic acids as the sole reagents. Hydrotrifluoro-, difluoro-, monofluoro- and perfluoroalkylation are all demonstrated, with broad scope, mild conditions (redox neutral) and potential for late-stage modification of bioactive molecules. Critical to success is overcoming the exceedingly high redox potential of feedstock fluoroalkyl carboxylic acids such as trifluoroacetic acid by leveraging cooperative earth-abundant, inexpensive iron and redox-active thiol catalysis, enabling these reagents to be directly used as hydroperfluoroalkylation donors without pre-activation. Preliminary mechanistic studies support the radical nature of this cooperative process.
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Affiliation(s)
- Kang-Jie Bian
- Department of Chemistry, Rice University, Houston, TX, USA
| | - Yen-Chu Lu
- Department of Chemistry, Rice University, Houston, TX, USA
| | - David Nemoto
- Department of Chemistry, Rice University, Houston, TX, USA
| | - Shih-Chieh Kao
- Department of Chemistry, Rice University, Houston, TX, USA
| | - Xiaowei Chen
- Department of Chemistry, Rice University, Houston, TX, USA
| | - Julian G West
- Department of Chemistry, Rice University, Houston, TX, USA.
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16
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Zhong T, Gu C, Li Y, Huang J, Han J, Zhu C, Han J, Xie J. Manganese/Cobalt Bimetallic Relay Catalysis for Divergent Dehydrogenative Difluoroalkylation of Alkenes. Angew Chem Int Ed Engl 2023; 62:e202310762. [PMID: 37642584 DOI: 10.1002/anie.202310762] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 08/21/2023] [Accepted: 08/29/2023] [Indexed: 08/31/2023]
Abstract
The involvement of manganese radical for halogen atom transfer (XAT) reactions has been esteemed as one reliable method but encountered with limited catalytic models. In this paper, a novel bimetallic relay catalysis of Mn2 (CO)10 and cobaloxime has been developed for divergent dehydrogenative difluoroalkylation of alkenes using commercially available difluoroalkyl bromides. A wide range of structurally diverse terminal, cyclic and internal alkenes as well as tetrasubstituted alkenes are found to be good coupling partners to deliver difluoroalkylated allylic products and difluoromethylated cyclic products, accompanied with the production of H2 as the by-product. This bimetallic relay strategy features broad substrate scope, mild reaction conditions and excellent functional group compatibility. Its success represents an important step-forward to expedite the construction of a rich library of difluoroalkylated products.
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Affiliation(s)
- Tao Zhong
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chengyihan Gu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Yuhang Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jun Huang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jian Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Chengjian Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Jie Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi, 830017, China
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17
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Zhao H, Gu Y, Shen Q. [(SIPr)Ag(CF 2 H)]: A Shelf-Stable, Versatile Difluoromethylation Reagent. CHEM REC 2023; 23:e202300124. [PMID: 37194962 DOI: 10.1002/tcr.202300124] [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: 04/09/2023] [Revised: 05/05/2023] [Indexed: 05/18/2023]
Abstract
Due to its unique physical and electrophilic properties, the difluoromethyl group (-CF2 H) has been playing an irreplaceable role in the field of pharmaceutical and agrochemical industry. Methods that could efficiently incorporate the difluoromethyl group into the target molecules are increasing in the recent years. Developing a stable and efficient difluoromethylating reagent is thus highly attractive. In this review, we describe the development of a nucleophilic difluoromethylation reagent [(SIPr)Ag(CF2 H)], including its elemental reaction, difluoromethylation reaction with different types of electrophiles, and its application in the synthesis of a nucleophilic and an electrophilic difluoromethylthiolating reagent.
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Affiliation(s)
- Haiwei Zhao
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Yang Gu
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Qilong Shen
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
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18
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Yedase GS, Arif M, Kuniyil R, Yatham VR. Photocatalytic Hydro Tri/Difluoromethylation of Alkenes with Bench Stable Tri/Difluoromethylating Reagents. Org Lett 2023; 25:6200-6205. [PMID: 37578816 DOI: 10.1021/acs.orglett.3c02413] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Herein, we demonstrate the synthesis and characterization of bench stable tri/difluoromethylating reagents and their potential applications in redox neutral hydro tri/difluoromethylation of alkenes enabled by visible light. The new tri/difluoromethylating reagents are obtained on a gram-scale through simply cyclocondensation of commercially available anthranilamide with phenyltrifluoro or difluoromethyl ketone. Preliminary mechanistic studies indicated that a canonical photoredox catalytic cycle is being operative. DFT studies support this and further reveal that deprotonation occurs before radical cleavage. DFT studies also show that the better yield with HCF2 reagent is attributed to the favorable expulsion of the corresponding radical moiety.
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Affiliation(s)
- Girish Suresh Yedase
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
| | - Munaifa Arif
- Department of Chemistry, Indian Institute of Technology Palakkad, Palakkad 678557, India
| | - Rositha Kuniyil
- Department of Chemistry, Indian Institute of Technology Palakkad, Palakkad 678557, India
| | - Veera Reddy Yatham
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
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19
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Pan S, Chen F, Zhang Y, Shao L, Chu L. Nickel-Catalyzed Markovnikov-Selective Hydrodifluoromethylation of Alkynes Using BrCF 2 H. Angew Chem Int Ed Engl 2023; 62:e202305426. [PMID: 37293885 DOI: 10.1002/anie.202305426] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/07/2023] [Accepted: 06/09/2023] [Indexed: 06/10/2023]
Abstract
A Markovnikov-selective hydrodifluoromethylation of alkynes with BrCF2 H via nickel catalysis is described. This protocol proceeds via a migratory insertion of nickel hydride to alkyne followed by a CF2 H-coupling, enabling straightforward access to diverse branched CF2 H-alkenes with high efficiency and exclusive regioselectivity. The mild condition applies to a wide array of aliphatic and aryl alkynes with good functional group compatibility. Mechanistic studies are presented to support the proposed pathway.
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Affiliation(s)
- Shiwei Pan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Center for Advanced Low-dimension Materials, Donghua University, Shanghai, 201620, China
| | - Fan Chen
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Center for Advanced Low-dimension Materials, Donghua University, Shanghai, 201620, China
| | - Yanyan Zhang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Center for Advanced Low-dimension Materials, Donghua University, Shanghai, 201620, China
| | - Liang Shao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Center for Advanced Low-dimension Materials, Donghua University, Shanghai, 201620, China
| | - Lingling Chu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Center for Advanced Low-dimension Materials, Donghua University, Shanghai, 201620, China
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20
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Wei HZ, Shi M, Wei Y. Visible-light-induced reactions of methylenecyclopropanes (MCPs). Chem Commun (Camb) 2023; 59:2726-2738. [PMID: 36752186 DOI: 10.1039/d2cc06957a] [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
Diverse, visible-light-induced transformations of methylenecyclopropanes (MCPs) have been reported in recent years, attracting significant attention from synthetic chemists. As readily accessible strained molecules, MCPs have sufficient reactivity to selectively generate different target products, through reactions with various radical species upon visible-light irradiation under regulated reaction conditions. These transformations can be classified into three subcategories of reaction pathway, forming ring-opened products, cyclopropane derivatives, and alkynes. These products include pharmaceutical intermediates and polycyclic/heterocyclic compounds that are challenging to obtain using traditional methods. This review summarizes the recent advancements in this field.
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Affiliation(s)
- Hao-Zhao Wei
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Min Shi
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China. .,Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Yin Wei
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China.
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21
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Wang J, Luo Z, Wu Y, Tang Y, Yang X, Tsui GC. Copper-Catalyzed Visible-Light-Induced Allylic Difluoromethylation of Unactivated Alkenes Using Difluoroacetic Acid. Org Lett 2023; 25:1045-1049. [PMID: 36752311 DOI: 10.1021/acs.orglett.3c00265] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We herein describe a straightforward allylic difluoromethylation reaction of unactivated alkenes. Compared to cross-couplings of prefunctionalized allylic substrates for the construction of allylic CF2H bonds, this reaction employs readily available alkenes as substrates under mild conditions. Difluoroacetic acid is used as an inexpensive and easy-to-handle source of CF2H radical under visible light irradiation with PIDA. The copper catalyst plays an important role of diverting the reaction pathway toward allylic difluoromethylation as opposed to previously found hydrodifluoromethylation.
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Affiliation(s)
- Jinlian Wang
- College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Ziwei Luo
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Yili Wu
- College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Yihan Tang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Xinkan Yang
- College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Gavin Chit Tsui
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
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22
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Shen ZJ, Zhu C, Zhang X, Yang C, Rueping M, Guo L, Xia W. Organoboron Reagent-Controlled Selective (Deutero)Hydrodefluorination. Angew Chem Int Ed Engl 2023; 62:e202217244. [PMID: 36525004 DOI: 10.1002/anie.202217244] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
(Deuterium-labeled) CF2 H- and CFH2 -moieties are of high interest in drug discovery. The high demand for the incorporation of these fluoroalkyl moieties into molecular structures has witnessed significant synthetic progress, particularly in the (deutero)hydrodefluorination of CF3 -containing compounds. However, the controllable replacement of fluorine atoms while maintaining high chemoselectivity remains challenging. Herein, we describe the development of a selective (deutero)hydrodefluorination reaction via electrolysis. The reaction exhibits a remarkable chemoselectivity control, which is enabled by the addition of different organoboron sources. The procedure is operationally simple and scalable, and provides access in one step to high-value building blocks for application in medicinal chemistry. Furthermore, density functional theory (DFT) calculations have been carried out to investigate the reaction mechanism and to rationalize the chemoselectivity observed.
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Affiliation(s)
- Zheng-Jia Shen
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Chen Zhu
- KAUST Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Xiao Zhang
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Chao Yang
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Magnus Rueping
- KAUST Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Lin Guo
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Wujiong Xia
- State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China.,School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007, China
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23
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Bai D, Guo Y, Ma D, Guo X, Wu H. Copper-Catalyzed Hydroamination of gem-Difluoroalkenes Access to Diversified α-Difluoromethyl Amines. Org Lett 2023; 25:533-537. [PMID: 36637250 DOI: 10.1021/acs.orglett.2c04278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The difluoromethyl group (CF2H) is of great importance in medicinal chemistry. We report herein an efficient method for the synthesis of diversified α-difluoromethyl amines through copper-catalyzed hydroamination of gem-difluoroalkenes, where the C-N bond formed via a α-CF2H transition-metal intermediate. This new reaction proceeds through Cu-H insertion to gem-difluoroalkenes and gives valuable alkyl-CF2H-containing compounds, which overcome the much more challenged β-F elimination from α-fluoroalkyl organocopper species. The reaction exhibits broad substrate scope with readily available starting materials and commercial catalysis.
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Affiliation(s)
- Dachang Bai
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Pingyuan Laboratory, Henan Normal University, Xinxiang 453007, China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P R China
| | - Yuanyuan Guo
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Pingyuan Laboratory, Henan Normal University, Xinxiang 453007, China
| | - Dandan Ma
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Pingyuan Laboratory, Henan Normal University, Xinxiang 453007, China
| | - Xiuli Guo
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Pingyuan Laboratory, Henan Normal University, Xinxiang 453007, China
| | - Hao Wu
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Pingyuan Laboratory, Henan Normal University, Xinxiang 453007, China
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24
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Abstract
The emergence of modern photocatalysis, characterized by mildness and selectivity, has significantly spurred innovative late-stage C-H functionalization approaches that make use of low energy photons as a controllable energy source. Compared to traditional late-stage functionalization strategies, photocatalysis paves the way toward complementary and/or previously unattainable regio- and chemoselectivities. Merging the compelling benefits of photocatalysis with the late-stage functionalization workflow offers a potentially unmatched arsenal to tackle drug development campaigns and beyond. This Review highlights the photocatalytic late-stage C-H functionalization strategies of small-molecule drugs, agrochemicals, and natural products, classified according to the targeted C-H bond and the newly formed one. Emphasis is devoted to identifying, describing, and comparing the main mechanistic scenarios. The Review draws a critical comparison between established ionic chemistry and photocatalyzed radical-based manifolds. The Review aims to establish the current state-of-the-art and illustrate the key unsolved challenges to be addressed in the future. The authors aim to introduce the general readership to the main approaches toward photocatalytic late-stage C-H functionalization, and specialist practitioners to the critical evaluation of the current methodologies, potential for improvement, and future uncharted directions.
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Affiliation(s)
- Peter Bellotti
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149Münster, Germany
| | - Huan-Ming Huang
- School of Physical Science and Technology, ShanghaiTech University, 201210Shanghai, China
| | - Teresa Faber
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149Münster, Germany
| | - Frank Glorius
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149Münster, Germany
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25
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Zhu M, Tian Y, Sha J, Fu W. Photocatalytic radical cascade cyclization of
N
‐(o–cyanobiaryl) acrylamides: access to CF
2
H‐functionalized pyrido[4,3,2‐gh] phenanthridines. ChemistrySelect 2022. [DOI: 10.1002/slct.202203986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Mei Zhu
- College of Food and Drug Luoyang Normal University 471934 Luoyang P. R. China
| | - Yunfei Tian
- College of Chemistry and Chemical Engineering Henan Key Laboratory of Fuction-Oriented Porous Materials Luoyang Normal University 471022 Luoyang P. R. China
| | - Jinyu Sha
- College of Food and Drug Luoyang Normal University 471934 Luoyang P. R. China
| | - Weijun Fu
- College of Chemistry and Chemical Engineering Henan Key Laboratory of Fuction-Oriented Porous Materials Luoyang Normal University 471022 Luoyang P. R. China
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26
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Chen F, Xu XH, Chu L, Qing FL. Visible-Light-Induced Nickel-Catalyzed Radical Cross-Couplings to Access α-Aryl-α-trifluoromethyl Alcohols. Org Lett 2022; 24:9332-9336. [PMID: 36484514 DOI: 10.1021/acs.orglett.2c03943] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A photochemically induced nickel-catalyzed radical cross-coupling of phthalimido trifluoroethanol with aryl bromides to furnish α-aryl-α-trifluoromethyl alcohols is reported. This reaction proceeds via a photoinduced charge transfer of an electron donor-acceptor complex between Hantzsch ester and phthalimido trifluoroethanol, followed by 1,2-hydrogen atom transfer, to generate the α-hydroxytrifluoroethyl radical for the cross-coupling of aryl bromides. No exogenous photocatalysts or stoichiometric metal reductants are required in this mild and operationally simple protocol. Broad substrate compatibility and excellent functional group tolerance are observed.
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Affiliation(s)
- Feng Chen
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Xiu-Hua Xu
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Lingling Chu
- College of Chemistry and Chemical Engineering, Donghua University, 2999 North Renmin Lu, Shanghai 201620, China
| | - Feng-Ling Qing
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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27
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Zhang FX, Lin JH, Xiao JC. Difluoromethylsulfonyl Imidazolium Salt for Difluoromethylation of Alkenes. Org Lett 2022; 24:7611-7616. [PMID: 36201292 DOI: 10.1021/acs.orglett.2c03073] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Herein, we describe the design and synthesis of a difluoromethylsulfonyl imidazolium salt, which can act as a radical difluoromethylation reagent to achieve the challenging amino- and oxy-difluoromethylation of alkenes. Notably, the three steps for the synthesis of the imidazolium salt do not require any tedious distillation or column chromatography purification process, and the amino- and oxy-difluoromethylation paths are simply determined by the selection of reaction solvents.
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Affiliation(s)
- Feng-Xu Zhang
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, 200032 Shanghai, China
| | - Jin-Hong Lin
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, 200032 Shanghai, China.,Department of Chemistry, Innovative Drug Research Center, Shanghai University, 200444 Shanghai, China
| | - Ji-Chang Xiao
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, 200032 Shanghai, China
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28
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Wang P, Zhang H, Zhao M, Ji S, Lin L, Yang N, Nie X, Song J, Liao S. Radical Hydro‐Fluorosulfonylation of Unactivated Alkenes and Alkynes. Angew Chem Int Ed Engl 2022; 61:e202207684. [DOI: 10.1002/anie.202207684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Indexed: 12/15/2022]
Affiliation(s)
- Peng Wang
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University) State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Fuzhou 350108 China
| | - Honghai Zhang
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University) State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Fuzhou 350108 China
| | - Mingqi Zhao
- College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou 450001 China
| | - Shuangshuang Ji
- College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou 450001 China
| | - Lu Lin
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University) State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Fuzhou 350108 China
| | - Na Yang
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University) State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Fuzhou 350108 China
| | - Xingliang Nie
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University) State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Fuzhou 350108 China
| | - Jinshuai Song
- College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou 450001 China
| | - Saihu Liao
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University) State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Fuzhou 350108 China
- Beijing National Laboratory of Molecular Science (BNLMS) Beijing 100190 China
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29
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Kim S, Hwang KH, Park HG, Kwak J, Lee H, Kim H. Radical hydrodifluoromethylation of unsaturated C-C bonds via an electroreductively triggered two-pronged approach. Commun Chem 2022; 5:96. [PMID: 36697867 PMCID: PMC9814520 DOI: 10.1038/s42004-022-00697-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 06/27/2022] [Indexed: 01/28/2023] Open
Abstract
Due to its superior ability in controlling pharmaceutical activity, the installation of difluoromethyl (CF2H) functionality into organic molecules has been an area of intensive research. In this context, difluoromethylation of C-C π bonds mediated by a CF2H radical have been pursued as a central strategy to grant access to difluoromethylated hydrocarbons. However, early precedents necessitate the generation of oxidative chemical species that can limit the generality and utility of the reaction. We report here the successful implementation of radical hydrodifluoromethylation of unsaturated C-C bonds via an electroreductively triggered two-pronged approach. Preliminary mechanistic investigations suggest that the key distinction of the present strategy originates from the reconciliation of multiple redox processes under highly reducing electrochemical conditions. The reaction conditions can be chosen based on the electronic properties of the alkenes of interest, highlighting the hydrodifluoromethylation of both unactivated and activated alkenes. Notably, the reaction delivers geminal (bis)difluoromethylated products from alkynes in a single step by consecutive hydrodifluoromethylation, granting access to an underutilized 1,1,3,3-tetrafluoropropan-2-yl functional group. The late-stage hydrodifluoromethylation of densely functionalized pharmaceutical agents is also presented.
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Affiliation(s)
- Seonyoung Kim
- grid.255649.90000 0001 2171 7754Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, 03760 Republic of Korea
| | - Keon Ha Hwang
- grid.29869.3c0000 0001 2296 8192Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114 Republic of Korea ,grid.254230.20000 0001 0722 6377Graduate School of New Drug Discovery and Development, Chungnam University, Daejeon, 34134 Republic of Korea
| | - Hyeong Gyu Park
- grid.29869.3c0000 0001 2296 8192Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114 Republic of Korea ,grid.254230.20000 0001 0722 6377Graduate School of New Drug Discovery and Development, Chungnam University, Daejeon, 34134 Republic of Korea
| | - Jaesung Kwak
- grid.29869.3c0000 0001 2296 8192Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114 Republic of Korea
| | - Hyuk Lee
- grid.29869.3c0000 0001 2296 8192Infectious Diseases Therapeutic Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114 Republic of Korea
| | - Hyunwoo Kim
- grid.49100.3c0000 0001 0742 4007Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, 37673 Republic of Korea
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30
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Wang P, Zhang H, Zhao M, Ji S, Lin L, Yang N, Nie X, Song J, Liao S. Radical Hydro‐Fluorosulfonylation of Unactivated Alkenes and Alkynes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207684] [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)
- Peng Wang
- Fuzhou University College of Chemistry CHINA
| | | | - Mingqi Zhao
- Zhengzhou University College of Chemistry and Molecular Engineering CHINA
| | - Shuangshuang Ji
- Zhengzhou University College of Chemistry and Molecular Engineering CHINA
| | - Lu Lin
- Fuzhou University College of Chemistry CHINA
| | - Na Yang
- Fuzhou University College of Chemistry CHINA
| | | | - Jinshuai Song
- Zhengzhou University College of Chemistry and Molecular Engineering CHINA
| | - Saihu Liao
- Fuzhou University College of Chemistry 2 Xueyuan RoadUniversity Town 350108 Fuzhou CHINA
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31
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Zhang ZQ, Sang YQ, Wang CQ, Dai P, Xue XS, Piper JL, Peng ZH, Ma JA, Zhang FG, Wu J. Difluoromethylation of Unactivated Alkenes Using Freon-22 through Tertiary Amine-Borane-Triggered Halogen Atom Transfer. J Am Chem Soc 2022; 144:14288-14296. [PMID: 35895322 DOI: 10.1021/jacs.2c05356] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The application of abundant and inexpensive fluorine feedstock sources to synthesize fluorinated compounds is an appealing yet underexplored strategy. Here, we report a photocatalytic radical hydrodifluoromethylation of unactivated alkenes with an inexpensive industrial chemical, chlorodifluoromethane (ClCF2H, Freon-22). This protocol is realized by merging tertiary amine-ligated boryl radical-induced halogen atom transfer (XAT) with organophotoredox catalysis under blue light irradiation. A broad scope of readily accessible alkenes featuring a variety of functional groups and drug and natural product moieties could be selectively difluoromethylated with good efficiency in a metal-free manner. Combined experimental and computational studies suggest that the key XAT process of ClCF2H is both thermodynamically and kinetically favored over the hydrogen atom transfer pathway owing to the formation of a strong boron-chlorine (B-Cl) bond and the low-lying antibonding orbital of the carbon-chlorine (C-Cl) bond.
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Affiliation(s)
- Zhi-Qi Zhang
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, P. R. of China.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Yue-Qian Sang
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, P. R. of China
| | - Cheng-Qiang Wang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Peng Dai
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Xiao-Song Xue
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, P. R. of China
| | - Jared L Piper
- Pfizer Worldwide Research and Development Medicine, Eastern Point Rd, Groton, Connecticut 06340, United States
| | - Zhi-Hui Peng
- Pfizer Worldwide Research and Development Medicine, Eastern Point Rd, Groton, Connecticut 06340, United States
| | - Jun-An Ma
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, P. R. of China.,Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Frontiers Science Center for Synthetic Biology (Ministry of Education), and Tianjin Collaborative Innovation Centre of Chemical Science & Engineering, Tianjin University, Tianjin 300072, P. R. of China
| | - Fa-Guang Zhang
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, P. R. of China.,Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Frontiers Science Center for Synthetic Biology (Ministry of Education), and Tianjin Collaborative Innovation Centre of Chemical Science & Engineering, Tianjin University, Tianjin 300072, P. R. of China
| | - Jie Wu
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou 350207, P. R. of China.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
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32
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Xiang J, Patureau FW. Cross Dehydrogenative Coupling of Chloro‐ and Fluoroalkanes with Methylarenes. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202200130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Jia‐Xiang Xiang
- Institute of Organic Chemistry RWTH Aachen University Landoltweg 1 52074 Aachen Germany
| | - Frederic W. Patureau
- Institute of Organic Chemistry RWTH Aachen University Landoltweg 1 52074 Aachen Germany
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33
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She K, Liang F, Tian S, Wang H, Tsui GC, Wang Q. Organocatalytic Three-Component Acyldifluoromethylation of Vinylarenes via N-Heterocyclic Carbene-Catalyzed Radical Relay. Org Lett 2022; 24:4840-4844. [PMID: 35758320 DOI: 10.1021/acs.orglett.2c02093] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We herein describe an N-hetercyclic carbene-catalyzed three-component acyldifluoromethylation of vinylarenes, aldehydes, and NaSO2CF2H. This organocatalytic approach provides a practical route for the synthesis of pharmaceutically relevant α-aryl-β-difluormethyl ketones without the need for transition metals or photocatalysts. The late-stage acyldifluoromethylation of drug analogues was also demonstrated. The reaction design employs NaSO2CF2H as the source of the CF2H radical in the presence of an oxidant for the radical relay.
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Affiliation(s)
- Kun She
- School of Chemistry and Pharmaceutical Sciences, State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, Guangxi Normal University, Guilin, Guangxi 541004, P. R. China
| | - Feng Liang
- School of Chemistry and Pharmaceutical Sciences, State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, Guangxi Normal University, Guilin, Guangxi 541004, P. R. China
| | - Shichao Tian
- School of Chemistry and Pharmaceutical Sciences, State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, Guangxi Normal University, Guilin, Guangxi 541004, P. R. China
| | - Hengshan Wang
- School of Chemistry and Pharmaceutical Sciences, State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, Guangxi Normal University, Guilin, Guangxi 541004, P. R. China
| | - Gavin Chit Tsui
- Department of Chemistry, The Chinese University of Hong Kong, New Territories, Hong Kong, P. R. China
| | - Quande Wang
- School of Chemistry and Pharmaceutical Sciences, State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative Innovation Center for Guangxi Ethnic Medicine, Guangxi Normal University, Guilin, Guangxi 541004, P. R. China
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34
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Guo C, Han X, Feng Y, Liu Z, Li Y, Liu H, Zhang L, Dong Y, Li X. Straightforward Synthesis of Alkyl Fluorides via Visible-Light-Induced Hydromono- and Difluoroalkylations of Alkenes with α-Fluoro Carboxylic Acids. J Org Chem 2022; 87:9232-9241. [PMID: 35748751 DOI: 10.1021/acs.joc.2c00965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We herein report the first visible-light-induced hydromono- and difluoroalkylations of alkenes with inexpensive and easily accessible α-fluoro carboxylic acids. This metal-free protocol exhibits mild conditions, high efficiency, and excellent functional-group tolerance, providing a straightforward approach to mono- and difluoroalkylated alkanes. Moreover, the fluorine effect on the hydrofluoroalkylation reaction is discussed in detail.
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Affiliation(s)
- Chunfang Guo
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China.,Shandong Vocational College of Light Industry, Zhoucun Mishan Road, Zibo 255300, P. R. China
| | - Xuliang Han
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Yu Feng
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Zhaolong Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Yueyun Li
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Hui Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Lizhi Zhang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Yunhui Dong
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China
| | - Xinjin Li
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255000, P. R. China.,Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
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35
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Abstract
With the continued interest in the properties of the difluoromethyl (CF2H) group, small molecules with alkyl-CF2H motifs have gained increasing attention. However, concise and efficient synthetic protocols to achieve these structures are still urgently needed. Herein, we report a new acyldifluoromethylation of inert alkenes via a synergistic NHC-photoredox catalysis featuring broad substrate scope and good functional group tolerance.
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Affiliation(s)
- Bei Zhang
- School of Pharmaceutical Sciences, Tsinghua University, Beijing 100084, China
| | - Jian Wang
- College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China.,School of Pharmaceutical Sciences, Tsinghua University, Beijing 100084, China
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36
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Wang L, Zhang Y, Zhu T, Wu J. Difluoromethylarylation of Alkynes from [Bis(difluoroacetoxy)iodo]benzene: Access to CF 2H-Containing Dibenzazepines. J Org Chem 2022; 87:7551-7556. [PMID: 35549257 DOI: 10.1021/acs.joc.2c00584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A photoinduced radical difluoromethylarylation via tandem addition-cyclization of alkynes with easily available [bis(difluoroacetoxy)iodo]benzene is accomplished, providing a straightforward and practical route for the construction of difluoromethylated dibenzazepines. Various sensitive functional groups can be compatible under photoinduced conditions. Mechanism investigation reveals that this transformation is initiated by the addition of alkyne with difluoromethyl radical, generated in situ from [bis(difluoroacetoxy)iodo]benzene.
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Affiliation(s)
- Luoyu Wang
- School of Pharmaceutical and Materials Engineering & Institute for Advanced Studies, Taizhou University, 1139 Shifu Avenue, Taizhou 318000, China
| | - Yan Zhang
- School of Pharmaceutical and Materials Engineering & Institute for Advanced Studies, Taizhou University, 1139 Shifu Avenue, Taizhou 318000, China
| | - Tonghao Zhu
- School of Pharmaceutical and Materials Engineering & Institute for Advanced Studies, Taizhou University, 1139 Shifu Avenue, Taizhou 318000, 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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37
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Guo F, Wang H, Ye X, Tan CH. Advanced Synthesis Using Photocatalysis Involved Dual Catalytic System. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Fenfen Guo
- Zhejiang University of Technology College of Pharmaceutical Science CHINA
| | - Hong Wang
- Zhejiang University of Technology College of Pharmaceutical Science CHINA
| | - Xinyi Ye
- Zhejiang University of Technology College of Pharmaceutical Science 18 Chaowang Road 310014 Hangzhou CHINA
| | - Choon-Hong Tan
- Nanyang Technological University School of Physical and Mathematical Sciences SINGAPORE
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38
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Zhou T, Liu R, Wang X, Rui M, Zhao X, Lu K. Visible‐light Induced Ipso‐Difluoromethylation of N‐arylpropiolamides to Synthesize 3‐difluoromethyl Spiro[4.5]trienones. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202200154] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ting Zhou
- Tianjin University of Science and Technology Chemistry Tianjin CHINA
| | - Ruiyue Liu
- Tianjin University of Science and Technology Chemistry Tianjin CHINA
| | - Xiuxiu Wang
- Tianjin University of Science and Technology Chemistry Tianjin CHINA
| | - Mingyang Rui
- Tianjin University of Science and Technology Chemistry Tianjin CHINA
| | - Xia Zhao
- Tianjin University of Science and Technology Chemistry Tianjin CHINA
| | - Kui Lu
- Tianjin University of Science & Technology Department of Pharmaceutical Engineering No.29, 13th AvenueTianjin Economic and Technological Development Area 300457 Tianjin CHINA
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39
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Visible-light-induced direct hydrodifluoromethylation of alkenes with difluoromethyltriphenylphosphonium iodide salt. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.04.071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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40
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Wang X, Liu R, Zhang S, Zhou T, Zhao X, Lu K. Visible-light-induced Radical Cyclization of N-allylbenzamide with [Bis(difluoroacetoxy)iodo]benzene to Difluoromethylated Dihydroisoquinolinones. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.153761] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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41
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Zhu YY, Liu S, Huang Y, Qing FL, Xu XH. Photoredox catalyzed difluoro(phenylthio)methylation of 2,3-allenoic acids with {difluoro(phenylthio)methyl}triphenylphosphonium triflate. J Fluor Chem 2022. [DOI: 10.1016/j.jfluchem.2022.109969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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42
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Zhu W, Xi H, Jiao W, Huang L, Wang L, Wu J. Difunctionalization of gem-Difluoroalkenes via Photoredox Catalysis: Synthesis of Diverse α,α-Difluoromethyl-β-alkoxysulfones. Org Lett 2022; 24:720-725. [PMID: 34981944 DOI: 10.1021/acs.orglett.1c04165] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Visible-light-promoted alkoxysulfonylation of gem-difluoroalkenes using sulfonyl chlorides and alcohols has been developed. The reaction exhibits a relatively broad substrate scope with excellent functional group compatibility. This synthesis method includes an atom transfer radical addition-like process. The products can be used as platform molecules for further modification.
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Affiliation(s)
- Wenjuan Zhu
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Hui Xi
- Zhengzhou Tobacco Research Institute of China National Tobacco Company, Zhengzhou 450001, P. R. China
| | - Wenyang Jiao
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Lihua Huang
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Lianjie Wang
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Junliang Wu
- College of Chemistry and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, P. R. China
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43
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Bai D, Wu F, Chang L, Wang M, Wu H, Chang J. Highly Regio‐ and Enantioselective Hydrosilylation of
gem
‐Difluoroalkenes by Nickel Catalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Dachang Bai
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang 453007 China
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 P.R. China
| | - Fen Wu
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang 453007 China
| | - Lingna Chang
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang 453007 China
| | - Manman Wang
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang 453007 China
| | - Hao Wu
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang 453007 China
| | - Junbiao Chang
- NMPA Key Laboratory for Research and Evaluation of Innovative Drug Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University Xinxiang 453007 China
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44
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Xiong W, Qin WB, Zhao YS, Fu KZ, Liu GK. Direct C(sp3)−H Difluoromethylation via Radical-Radical Cross-Coupling by Visible-Light Photoredox Catalysis. Org Chem Front 2022. [DOI: 10.1039/d2qo00192f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, the radical-radical cross-coupling strategy for direct difluoromethylation of C(sp3)−H bond is reported. This transformation was readily accomplished under transition metal-free photoredox catalysis in the presence of 3 mol% of...
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45
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Feng J, Jia X, Zhang S, Lu K, Cahard D. State of knowledge in photoredox-catalysed direct difluoromethylation. Org Chem Front 2022. [DOI: 10.1039/d2qo00551d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The combination of visible light photoredox catalysis with direct difluoromethylation has allowed the synthesis of a large choice of CF2H-containing value-added molecules under very mild reaction conditions.
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Affiliation(s)
- Jiaxu Feng
- China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P.R. China
- Department of Chemistry, College of Sciences, Tianjin University of Science & Technology, Tianjin 300457, P.R. China
| | - Xiaodong Jia
- China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P.R. China
| | - Shuyue Zhang
- China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P.R. China
| | - Kui Lu
- China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, P.R. China
- Department of Chemistry, College of Sciences, Tianjin University of Science & Technology, Tianjin 300457, P.R. China
| | - Dominique Cahard
- CNRS, UMR 6014 COBRA, Normandie Université, 76821 Mont Saint Aignan, France
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46
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Dolbier W, Wei S, Le S, Lei Z, Zhou L, Zhang Z. Difluoromethylarylation of α, β- Unsaturated Amides via a Photocatalytic Radical Smiles Rearrangement. Org Biomol Chem 2022; 20:2064-2068. [DOI: 10.1039/d2ob00186a] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A photocatalytic Smiles rearrangement, triggered by radical difluoromethylation of conjugated arylsulfonylated amides, was developed to construct both β-difluoromethyl amide and heterocyclic scaffolds selectively. This transformation features mild conditions and broad...
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47
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Chen J, Wu J. Nickel-Catalyzed Enantioselective Hydrosilylation of gem-Difluoroalkenes with Silanes. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202200017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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48
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Bai D, Wu F, Chang L, Wang M, Wu H, Chang J. Highly Regio- and Enantioselective Hydrosilylation of gem-Difluoroalkenes via Nickel Catalysis. Angew Chem Int Ed Engl 2021; 61:e202114918. [PMID: 34957676 DOI: 10.1002/anie.202114918] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Indexed: 11/10/2022]
Abstract
The synthesis of small organic molecules with a difluoromethylated stereocenter is particularly attractive in drug discovery. Herein, we developed an efficient method for the direct generation of difluoromethylated stereocenters through Ni(0)-catalyzed regio - and enantioselective hydrosilylation of gem -difluoroalkenes. The reaction also represents the enantioselective construction of carbon(sp 3 )-silicon bonds with nickel catalysis, which provides an atom- and step-economical synthesis route of high-value optically active α-difluoromethylsilanes. This protocol features with readily available starting materials and commercial chiral catalysis, broad substrates spanning a range of functional groups with high yield (up to 99% yield) and excellent enantioselectivity (up to 96% ee). The enantioenriched products undergo a variety of stereospecific transformations. Preliminary mechanistic studies were performed.
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Affiliation(s)
- Dachang Bai
- Henan Normal University, school of chemistry and chemical engineering, 46# jianshe road, 456007, xinxiang, CHINA
| | - Fen Wu
- Henan Normal University, School of Chemistry and Chemical Engineering, CHINA
| | - Lingna Chang
- Henan Normal University, School of Chemistry and Chemical Engineering, CHINA
| | - Manman Wang
- Henan Normal University, School of Chemistry and Chemical Engineering, CHINA
| | - Hao Wu
- Henan Normal University, School of Chemistry and Chemical Engineering, CHINA
| | - Junbiao Chang
- Henan Normal University, School of Chemistry and Chemical Engineering, CHINA
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49
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Dai P, Li C, Li Y, Zhu Y, Teng P, Gu Y, Zhang W. Direct Difluoromethylation of Heterocycles through Photosensitized Electron Transfer. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100896] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Peng Dai
- Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing 210095 China
| | - Chenxiao Li
- Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing 210095 China
| | - Yufei Li
- Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing 210095 China
| | - Yuchuan Zhu
- Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing 210095 China
| | - Peng Teng
- Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing 210095 China
| | - Yu‐Cheng Gu
- Syngenta Jealott's Hill International Research Centre Bracknell Berkshire RG42 6EY United Kingdom, UK
| | - Wei‐Hua Zhang
- Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing 210095 China
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50
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Liu Q, Lu Y, Sheng H, Zhang C, Su X, Wang Z, Chen X. Visible‐Light‐Induced Selective Photolysis of Phosphonium Iodide Salts for Monofluoromethylations. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Qiang Liu
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
| | - Yu Lu
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
| | - He Sheng
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
| | - Chao‐Shen Zhang
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiao‐Di Su
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
| | - Zhi‐Xiang Wang
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiang‐Yu Chen
- School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China
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