1
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Nie Z, Wu K, Zhan X, Yang W, Lian Z, Lin S, Wang SG, Yin Q. Palladium-catalyzed difluorocarbene transfer enables access to enantioenriched chiral spirooxindoles. Nat Commun 2024; 15:8510. [PMID: 39353887 PMCID: PMC11445564 DOI: 10.1038/s41467-024-52392-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Accepted: 09/03/2024] [Indexed: 10/03/2024] Open
Abstract
We disclose herein an unprecedented Pd-catalyzed difluorocarbene transfer reaction, which assembles a series of structurally interesting chiral spiro ketones with generally over 90% ee. Commercially available BrCF2CO2K serves as the difluorocarbene precursor, which is harnessed as a user-friendly and safe carbonyl source in this transformation. Preliminary mechanistic studies exclude the formation of free CO in the reaction process, and importantly, we also find that BrCF2CO2K outcompete gaseous CO and several common CO surrogates in this asymmetric process. The reaction mechanism, including the in-situ progressive release of the difluorocarbene, the rapid migratory insertion of ArPd(II) = CF2 species, and subsequent defluorination hydrolysis by water to introduce the carbonyl group, accounts for the overall high efficiency and uniqueness. This work clearly showcases the advantage and potential of the difluorocarbene in synthesis and supplies a mechanistically distinct route for asymmetric carbonylative cyclization reactions.
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Affiliation(s)
- Zhiwen Nie
- Shenzhen University of Advanced Technology, Shenzhen, 518055, P. R. China
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, P. R. China
| | - Keqin Wu
- Shenzhen University of Advanced Technology, Shenzhen, 518055, P. R. China
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Xiaohang Zhan
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, P. R. China
| | - Weiran Yang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Zhong Lian
- Department of Dermatology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, P. R. China
| | - Shaoquan Lin
- Shenzhen University of Advanced Technology, Shenzhen, 518055, P. R. China
| | - Shou-Guo Wang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, P. R. China
| | - Qin Yin
- Shenzhen University of Advanced Technology, Shenzhen, 518055, P. R. China.
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, P. R. China.
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2
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Pan S, Xie Q, Wang X, Huang R, Lu Y, Ni C, Hu J. Controllable Double Difluoromethylene Insertions into S-Cu Bonds: (Arylthio)tetrafluoroethylation of Aryl Iodides with TMSCF 2Br. Angew Chem Int Ed Engl 2024; 63:e202400839. [PMID: 38358953 DOI: 10.1002/anie.202400839] [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: 01/12/2024] [Revised: 02/14/2024] [Accepted: 02/14/2024] [Indexed: 02/17/2024]
Abstract
A new method of constructing "ArSCF2CF2Cu" from ArSCu and TMSCF2Br (TMS=trimethylsilyl) has been developed. The cross-coupling reactions of the obtained "ArSCF2CF2Cu" with diverse aryl iodides (Ar'I) provide an efficient access to Ar'CF2CF2SAr. Mechanistic studies demonstrate that the "ArSCF2CF2Cu" species were generated through controllable double difluoromethylene insertions into ArS-Cu bonds rather than the 1,2-addition of ArSCu to tetrafluoroethylene.
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Affiliation(s)
- Shitao Pan
- 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 Ling-Ling Road, Shanghai, 200032, China
| | - Qiqiang Xie
- 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 Ling-Ling Road, Shanghai, 200032, China
| | - Xiu Wang
- 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 Ling-Ling Road, Shanghai, 200032, China
| | - Rumin Huang
- 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 Ling-Ling Road, Shanghai, 200032, China
| | - Yuhao Lu
- 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 Ling-Ling Road, Shanghai, 200032, China
| | - Chuanfa Ni
- 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 Ling-Ling Road, Shanghai, 200032, China
| | - Jinbo Hu
- 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 Ling-Ling Road, Shanghai, 200032, China
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3
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Xie Q, Hu J. A Journey of the Development of Privileged Difluorocarbene Reagents TMSCF 2X (X = Br, F, Cl) for Organic Synthesis. Acc Chem Res 2024; 57:693-713. [PMID: 38354302 DOI: 10.1021/acs.accounts.3c00719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
ConspectusAs fluorine has played an increasingly important role in modulating the physical, chemical, and biological properties of organic molecules, the selective introduction of fluorine atom(s) or fluorinated moieties into target molecules has become a powerful tool in the development of new pharmaceuticals, agrochemicals, and functional materials. In this context, the difluoromethylene (CF2) and difluoromethyl (CF2H) groups are of special interest because of their ability to serve as bioisosteres of ethereal oxygen atoms and hydroxyl (OH) and thiol (SH) groups, respectively. Difluorocarbene is one of the most versatile reactive intermediates to incorporate CF2 and CF2H groups; however, before 2006, most of the previously known difluorocarbene reagents suffered from several drawbacks such as using ozone-depleting substances (ODSs), difficult-to-handle reagents, or harsh reaction conditions or having narrow substrate scope and/or low yields. Moreover, the reactivity of difluorocarbene generated from different precursors (reagents) was often unpredictable, since the difluorocarbene generation conditions (activation modes) of various difluorocarbene precursors are different, and these conditions may mismatch those required for subsequent difluorocarbene-involved transformations. Therefore, the development of new environmentally friendly and versatile difluorocarbene reagents, as well as the investigation of the mechanistic insights into difluorocarbene-involved reactions, has been highly desirable.In this Account, we summarize our contributions to the development of new difluorocarbene reagents and their applications in organic synthesis since 2006. We have developed seven new difluorocarbene reagents, including 2-chloro-2,2-difluoroacetophenone (1), chlorodifluoromethyl phenyl sulfone (2), S-difluoromethyl-S-phenyl-N-tosylsulfoximine (3), difluoromethyltri(n-butyl)ammonium chloride (4), (chlorodifluoromethyl)trimethylsilane (TMSCF2Cl, 5), (bromodifluoromethyl)trimethylsilane (TMSCF2Br, 6), and (trifluoromethyl)trimethylsilane (TMSCF3, 7). In this journey, we realized the key factor for an ideal difluorocarbene reagent that can be used for a broad range of reactions, that is, the reagent should allow various activation modes for the generation of difluorocarbene species, such as under basic/acidic/neutral conditions, at wide range of temperatures, and in different solvents, which are compatible with a wide range of difluorocarbene-involved transformations. Among all known difluorocarbene reagents, silanes TMSCF2X (X = Br, F, Cl) have stood out as privileged ones, which paves a new avenue for further developing difluorocarbene chemistry. In particular, TMSCF2Br was recognized as an "all-rounder": TMSCF2Br can be applied in almost all common difluorocarbene-involved reactions, and more importantly, TMSCF2Br also enables many other novel transformations that other difluorocarbene reagents cannot achieve, thanks to its unique structure and rich activation modes of releasing difluorocarbene under different reaction conditions. It can be expected that with the commercial availability of TMSCF2X reagents (X = Br, F, Cl) now, the development of difluorocarbene chemistry will be accelerated in the years to come.
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Affiliation(s)
- Qiqiang Xie
- 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 Ling-Ling Road, Shanghai 200032, China
| | - Jinbo Hu
- 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 Ling-Ling Road, Shanghai 200032, China
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4
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Liu W, Lan H, Huang JB, Liu W, Jiang KZ, Xiao X, Ni SF, Liu J, Bai Y, Shao X. Benzyl Deuteriodifluoromethyl Sulfoxide: An Easily Accessible and Stable Reagent for Direct Deuterodifluoromethylthiolation. Org Lett 2024; 26:687-691. [PMID: 38236133 DOI: 10.1021/acs.orglett.3c04082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
A new, stable and scalable reagent based on a sulfoxide skeleton for direct deuteriodifluoromethylthiolation has been developed. The reagent displays excellent reactivities toward Tf2O promoted C-H deuteriodifluoromethylthiolation of electron-rich arenes, indoles, alkenes, and intramolecular lactonization of 2-alkynylbenzoates. Moreover, high deuteration rates and good to excellent yields were achieved under metal-free reaction conditions. As a result, a wide range of deuteriodifluoromethylthilolated compounds were prepared, enabling further applications in drug discovery.
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Affiliation(s)
- Wen Liu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Huilin Lan
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Jia-Bo Huang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province, Shantou University, Shantou 515063, P. R. China
| | - Wenting Liu
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Ke-Zhi Jiang
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Xuqiong Xiao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Shao-Fei Ni
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province, Shantou University, Shantou 515063, P. R. China
| | - Jingsong Liu
- Zhejiang Key Laboratory of Ecological and Environmental Monitoring, Forewarning and Quality Control, Zhejiang Ecological and Environmental Monitoring Center, Hangzhou, 310015, P. R. China
| | - Ying Bai
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Xinxin Shao
- College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, P. R. China
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5
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Liu A, Zhang X, Zhao F, Ni C, Hu J. Controllable Fluorocarbon Chain Elongation: TMSCF 2Br-Enabled Trifluorovinylation and Pentafluorocyclopropylation of Aldehydes. J Am Chem Soc 2024; 146:1806-1812. [PMID: 38193677 DOI: 10.1021/jacs.3c12919] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Controllable fluorocarbon chain elongation (CFCE) is a promising yet underdeveloped strategy for the well-defined synthesis of structurally novel polyfluorinated compounds. Herein, the direct and efficient trifluorovinylation and pentafluorocyclopropylation of aldehydes are described by using TMSCF2Br (TMS = trimethylsilyl) as the sole fluorocarbon source, accomplishing the goals of CFCE from C1 to C2 and from C1 to C3, respectively. The key to the success of these CFCE processes lies in the unique and diversified chemical reactivity of TMSCF2Br, which can serve as two different precursors, namely, a TMSCF2 radical precursor and a difluorocarbene precursor. Various functional groups are amenable to this new synthetic protocol, providing streamlined access to a broad range of alcohols containing trifluorovinyl or pentafluorocyclopropyl moieties from abundantly available aldehydes. The potential utility of these methods is further demonstrated by the gram-scale synthesis, derivatization, and measurement of log P values of the products.
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Affiliation(s)
- An Liu
- 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 Ling-Ling Road, Shanghai 200032, China
| | - Xianghong Zhang
- 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 Ling-Ling Road, Shanghai 200032, China
| | - Feng 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 Ling-Ling Road, Shanghai 200032, China
| | - Chuanfa Ni
- 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 Ling-Ling Road, Shanghai 200032, China
| | - Jinbo Hu
- 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 Ling-Ling Road, Shanghai 200032, China
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6
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Sheng H, Chen Z, Song Q. Palladium-Catalyzed Difluorocarbene Transfer Enabled Divergent Synthesis of γ-Butenolides and Ynones from Iodobenzene and Terminal Alkynes. J Am Chem Soc 2024; 146:1722-1731. [PMID: 38173091 DOI: 10.1021/jacs.3c13044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Herein, we report a ligand-controlled palladium-catalyzed method that enables the synthesis of ynones and γ-butenolides with excellent regioselectivity from the same set of readily available aryl iodides, aryl acetylenes, and BrCF2CO2K. In this reaction, the [PdII]═CF2 does demonstrate electrophilicity and can generate CO readily when reacting with H2O. It is environmentally friendly and safe compared to traditional methods, and the current protocol enables us to afford ynones and γ-butenolides in high yields with excellent functionality tolerance. Moreover, esters can also be obtained with corresponding phenols and alcohols utilizing this strategy. The success of late-stage functionalization of bioactive compounds further illustrates the synthetic utility of this protocol in material development and drug discovery.
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Affiliation(s)
- Heyun Sheng
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
| | - Zhiwei Chen
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
| | - Qiuling Song
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
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7
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Hu C, Wang L, Wu Y, Zheng Y, Fu Y, Du Z. Synthesis of N-substituted phthalimides via Pd-catalyzed [4+1] cycloaddition reaction. Chem Commun (Camb) 2023. [PMID: 38014497 DOI: 10.1039/d3cc04534j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
A novel Pd-catalyzed assembly of N-substituted phthalimides by merging of [4+1] cycloaddition and difluorocarbene transfer carbonylation from 2-iodo-N-phenylbenzamides and difluorocarbene precursors is disclosed. Difluorocarbene acts as a carbonyl source and simultaneously forms one C-C bond, one C-N bond and one CO bond to produce N-substituted phthalimides in high yields.
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Affiliation(s)
- Chengxian Hu
- Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China.
| | - Lu Wang
- Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China.
| | - Yuanyuan Wu
- Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China.
| | - Yonglong Zheng
- Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China.
| | - Ying Fu
- Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China.
| | - Zhengyin Du
- Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. China.
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8
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Han X, Liu X, Len C, Liu L, Wang D, Zhang Y, Duan XH, Hu M. Photoredox-Catalyzed gem-Difluoromethylenation of Aliphatic Alcohols with 1,1-Difluoroalkenes to Access α,α-Difluoromethylene Ethers. J Org Chem 2023; 88:12744-12754. [PMID: 37610918 DOI: 10.1021/acs.joc.3c01428] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
A switchable synthesis of alcohols and ketones bearing a CF2-OR scaffold using visible-light promotion is described. The method of PDI catalysis is characterized by its ease of operation, broad substrate scopes, and the ability to switch between desired products without the need for transition metal catalysts. The addition or absence of a base plays a key role in controlling the synthesis of the major desired products.
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Affiliation(s)
- Xinxin Han
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xin Liu
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
| | - Christophe Len
- CNRS, Institute of Chemistry for Life and Health Sciences, Chimie ParisTech, PSL University, 11 rue Pierre et Marie Curie, F-75005 Paris, France
- Université de Technologie de Compiègne, Sorbonne Université, F-60203 Compiègne, France
| | - Le Liu
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
| | - Dongdong Wang
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yinbin Zhang
- Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710049, China
| | - Xin-Hua Duan
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
| | - Mingyou Hu
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
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9
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Ishu K, Prabhakar NS, Singh KN. A regioselective synthesis of β-difluoromethoxy vinyl sulfones via O-difluoromethylation of β-ketosulfones using sodium chlorodifluoroacetate. Org Biomol Chem 2023; 21:6588-6594. [PMID: 37528684 DOI: 10.1039/d3ob01142a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
A practical synthesis of new β-difluoromethoxy vinyl sulfones has been explored by O-difluoromethylation of β-ketosulfones using the inexpensive and easily workable sodium chlorodifluoroacetate as a difluorocarbene precursor. The strategy is convenient and regioselective, and features an adequate substrate scope and functional group tolerance.
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Affiliation(s)
- Km Ishu
- Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
| | - Neha Sharma Prabhakar
- Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
| | - Krishna Nand Singh
- Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
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10
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Zhou H, Pan R, Xu M, Ma J, Lin A, Yao H. Construction of oxygenated 2-azabicyclo[2.2.1]heptanes via palladium-catalyzed 1,2-aminoacyloxylation of cyclopentenes. Chem Commun (Camb) 2023; 59:3574-3577. [PMID: 36880405 DOI: 10.1039/d2cc06581a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
Herein, we describe a palladium-catalyzed 1,2-aminoacyloxylation of cyclopentenes to synthesize oxygenated 2-azabicyclo[2.2.1]heptanes. This reaction proceeds efficiently with a broad array of substrates. The products could be further functionalized to build up a library of bridged aza-bicyclic structures.
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Affiliation(s)
- Haipin Zhou
- College of Materials & Chemical Engineering, Chuzhou University, 1 West Huifeng Road, Chuzhou, 239000, P. R. China
- State Key Laboratory of Natural Medicines (SKLNM) and Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P. R. China.
| | - Rui Pan
- State Key Laboratory of Natural Medicines (SKLNM) and Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P. R. China.
| | - Menghua Xu
- State Key Laboratory of Natural Medicines (SKLNM) and Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P. R. China.
| | - Jiao Ma
- State Key Laboratory of Natural Medicines (SKLNM) and Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P. R. China.
| | - Aijun Lin
- State Key Laboratory of Natural Medicines (SKLNM) and Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P. R. China.
| | - Hequan Yao
- State Key Laboratory of Natural Medicines (SKLNM) and Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P. R. China.
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11
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Zhao YR, Ma ZY, Liu L, Gao P, Duan XH, Hu M. Synthesis of α-Difluoromethylene Ethers via Photoredox-Induced Hyperconjugative Ring Opening of gem-Difluorocyclopropanes. J Org Chem 2023; 88:3787-3793. [PMID: 36827360 DOI: 10.1021/acs.joc.2c03062] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
Fluorinated compounds have found widespread applications in pharmaceuticals, agrochemicals, and materials science. Precise construction of α-difluoromethylene ether (CF2-O) moiety in organic molecules is of high demand. Herein, a visible light-promoted reaction protocol for the synthesis of α-difluoromethylene ether from gem-difluorocyclopropane is described. The key ring-opening step is induced by hyperconjugative interaction of cyclopropane with photo-oxidized aromatic rings. This reaction is easy scale-up, and the products bearing a synthetic handle enable their further manipulation.
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Affiliation(s)
- Yu-Rou Zhao
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, China
| | - Zhi-Yong Ma
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, China
| | - Le Liu
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, China
| | - Pin Gao
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xin-Hua Duan
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, China
| | - Mingyou Hu
- School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University, Xi'an 710049, China.,Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
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12
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Liu A, Ni C, Xie Q, Hu J. Transition-Metal-Free Controllable Single and Double Difluoromethylene Formal Insertions into C-H Bonds of Aldehydes with TMSCF 2 Br. Angew Chem Int Ed Engl 2023; 62:e202217088. [PMID: 36517973 DOI: 10.1002/anie.202217088] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
We have developed a new strategy for controllable single and double difluoromethylene (CF2 ) formal insertions into C-H bonds of aldehydes with nearly full selectivity under transition-metal-free conditions. The key to the success of controllable CF2 insertions lies in the well-defined formation of 2,2-difluoroenolsilyl ether and 2,2,3,3-tetrafluorocyclopropanolsilyl ether intermediates using difluorocarbene reagent TMSCF2 Br (TMS=trimethylsilyl). These two intermediates can react with various electrophiles including proton sources and various halogenation reagents, allowing for the access to diverse arrays of ketones containing difluoromethylene (CF2 ) and tetrafluoroethylene (CF2 CF2 ) units. The first synthesis of relatively stable 2,2,3,3-tetrafluorocyclopropanolsilyl ethers has been achieved, which offers a new platform to explore other unknown chemical space.
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Affiliation(s)
- An Liu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Chuanfa Ni
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Qiqiang Xie
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
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13
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Li SW, Wang G, Ye ZS. Difluorocarbene Enabled Ester Insertion/1,4-Acyl Rearrangement of 2-Acetoxylpyridines: Modular Access to gem-Difluoromethylenated 2-Pyridones. Tetrahedron Lett 2023. [DOI: 10.1016/j.tetlet.2023.154413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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14
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Feng CC, Zhang SL. Direct formylation of phenols using difluorocarbene as a safe CO surrogate. Org Biomol Chem 2023; 21:728-731. [PMID: 36601719 DOI: 10.1039/d2ob02128e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A convenient method to prepare aryl formates is reported herein that exploits difluorocarbene to serve as a CO surrogate. This reaction is proposed to occur through a sequential O-difluoromethylation of phenol, followed by α-C-F bond functionalization of the resulting aryl difluoromethyl ether intermediate by phenol or moisture through fluorosemiacetal or orthoformate intermediates. Late-stage modification of biologically and materially active compounds is demonstrated.
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Affiliation(s)
- Cong-Cong Feng
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu Province, China.
| | - Song-Lin Zhang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu Province, China.
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15
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Newton JJ, Engüdar G, Brooke AJ, Nodwell MB, Horngren-Rhodes H, Martin RE, Schaffer P, Britton R, Friesen CM. Rapid 18 F- and 19 F-Difluoromethylation through Desulfurative Fluorination of Transient N-, O-, and C-Linked Dithioles. Chemistry 2023; 29:e202202862. [PMID: 36318597 DOI: 10.1002/chem.202202862] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/26/2022] [Accepted: 10/27/2022] [Indexed: 12/14/2022]
Abstract
The difluoromethyl group plays an important role in modern medicinal and agrochemistry. While several difluoromethylation reagents have been reported, these typically rely on difluoromethyl carbenes or anions, or target specific processes. Here, we describe a conceptually unique and general process for O-H, N-H and C-H difluoromethylation that involves the formation of a transient dithiole followed by facile desulfurative fluorination using silver(I) fluoride. We also introduce the 5,6-dimethoxy-1,3-benzodithiole (DMBDT) function, which undergoes sufficiently rapid desulfurative fluorination to additionally support 18 F-difluoromethylation. This new process is compatible with the wide range of functional groups typically encountered in medicinal chemistry campaigns, and the use of Ag18 F is demonstrated in the production of 18 F-labeled derivatives of testosterone, perphenazine, and melatonin, 58.0±2.2, 20.4±0.3 and 32.2±3.6 MBq μmol-1 , respectively. We expect that the DMBDT group and this 18 F/19 F-difluoromethylation process will inspire and support new efforts in medicinal chemistry, agrochemistry and radiotracer production.
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Affiliation(s)
- Josiah J Newton
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada.,Neufeld Science Centre, Department of Chemistry, Trinity Western University, 22500 University Drive, Langley, British Columbia, V2Y 1Y1, Canada
| | - Gökçe Engüdar
- Life Sciences Division, TRIUMF Vancouver, British Columbia, V6T 2A3(Canada), Department of Radiology, 775 Laurel Street, 11th floor, Vancouver, BC V5Z 1M9, Canada
| | - Alan J Brooke
- Neufeld Science Centre, Department of Chemistry, Trinity Western University, 22500 University Drive, Langley, British Columbia, V2Y 1Y1, Canada
| | - Matthew B Nodwell
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada
| | - Holly Horngren-Rhodes
- Neufeld Science Centre, Department of Chemistry, Trinity Western University, 22500 University Drive, Langley, British Columbia, V2Y 1Y1, Canada
| | - Rainer E Martin
- Medicinal Chemistry, Roche Pharma Research and Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Paul Schaffer
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada.,Life Sciences Division, TRIUMF Vancouver, British Columbia, V6T 2A3(Canada), Department of Radiology, 775 Laurel Street, 11th floor, Vancouver, BC V5Z 1M9, Canada
| | - Robert Britton
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada
| | - Chadron M Friesen
- Neufeld Science Centre, Department of Chemistry, Trinity Western University, 22500 University Drive, Langley, British Columbia, V2Y 1Y1, Canada
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16
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Luque-Navarro PM, Carrasco-Jiménez MP, Goracci L, Paredes JM, Espinar-Barranco L, Valverde-Pozo J, Torretta A, Parisini E, Mariotto E, Marchioro C, Laso A, Marco C, Viola G, Lanari D, López Cara LC. New bioisosteric sulphur-containing choline kinase inhibitors with a tracked mode of action. Eur J Med Chem 2023; 246:115003. [PMID: 36493617 DOI: 10.1016/j.ejmech.2022.115003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/28/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022]
Abstract
Since the identification of human choline kinase as a protein target against cancer progression, many compounds have been designed to inhibit its function and reduce the biosynthesis of phosphatidylcholine. Herein, we propose a series of bioisosteric inhibitors that are based on the introduction of sulphur and feature improved activity and lipophilic/hydrophilic balance. The evaluation of the inhibitory and of the antiproliferative properties of the PL (dithioethane) and FP (disulphide) libraries led to the identification of PL 48, PL 55 and PL 69 as the most active compounds of the series. Docking analysis using FLAP suggests that for hits to leads, binding mostly involves an interaction with the Mg2+ cofactor, or its destabilization. The most active compounds of the two series are capable of inducing apoptosis following the mitochondrial pathway and to significantly reduce the expression of anti-apoptotic proteins such as the Mcl-1. The fluorescence properties of the compounds of the PL library allowed the tracking of their mode of action, while PAINS (Pan Assays Interference Structures) filtration databases suggest the lack of any unspecific biological response.
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Affiliation(s)
- Pilar M Luque-Navarro
- Department of Pharmaceutical and Organic Chemistry, Faculty of Pharmacy, University of Granada, Campus of Cartuja s/n, Granada, 18071, Spain; Department of Pharmaceutical Sciences, University of Perugia, Perugia, 06123 Italy
| | - M Paz Carrasco-Jiménez
- Department of Biochemistry and Molecular Biology I, University of Granada, Campus of Fuentenueva s/n, Granada, 18071, Spain.
| | - Laura Goracci
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, 06123, Italy
| | - Jose M Paredes
- Department of Physical-Chemistry, Faculty of Pharmacy, University of Granada, Campus of Cartuja s/n, Granada, 18071, Spain
| | - Laura Espinar-Barranco
- Department of Physical-Chemistry, Faculty of Pharmacy, University of Granada, Campus of Cartuja s/n, Granada, 18071, Spain
| | - Javier Valverde-Pozo
- Department of Physical-Chemistry, Faculty of Pharmacy, University of Granada, Campus of Cartuja s/n, Granada, 18071, Spain
| | - Archimede Torretta
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy
| | - Emilio Parisini
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milano, 20133, Italy; Department of Biotechnology, Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, LV, 1006, Latvia; Department of Chemistry "G. Ciamician", University of Bologna, Via Selmi 2, Bologna, 40126, Italy
| | - Elena Mariotto
- Department of Woman's and Child's Health, Laboratory of Oncohematology, University of Padova, Padova, 35128, Italy
| | - Chiara Marchioro
- Department of Woman's and Child's Health, Laboratory of Oncohematology, University of Padova, Padova, 35128, Italy
| | - Alejandro Laso
- Department of Biochemistry and Molecular Biology I, University of Granada, Campus of Fuentenueva s/n, Granada, 18071, Spain
| | - Carmen Marco
- Department of Biochemistry and Molecular Biology I, University of Granada, Campus of Fuentenueva s/n, Granada, 18071, Spain
| | - Giampietro Viola
- Department of Woman's and Child's Health, Laboratory of Oncohematology, University of Padova, Padova, 35128, Italy; Istituto di Ricerca Pediatrica (IRP) Fondazione Città della Speranza, Corso Stati Uniti 4, Padova, 35128, Italy.
| | - Daniela Lanari
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, 06123 Italy.
| | - Luisa Carlota López Cara
- Department of Pharmaceutical and Organic Chemistry, Faculty of Pharmacy, University of Granada, Campus of Cartuja s/n, Granada, 18071, Spain.
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17
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Loison A, Hanquet G, Toulgoat F, Billard T, Panossian A, Leroux FR. Ketenimines as Intermediates To Access Difluoromethoxylated Scaffolds. Org Lett 2022; 24:8316-8321. [DOI: 10.1021/acs.orglett.2c03283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Anaïs Loison
- Université de Strasbourg, Université de Haute-Alsace, CNRS, ECPM, UMR 7042-LIMA, 67000, Strasbourg, France
| | - Gilles Hanquet
- Université de Strasbourg, Université de Haute-Alsace, CNRS, ECPM, UMR 7042-LIMA, 67000, Strasbourg, France
| | - Fabien Toulgoat
- Université Lyon 1, CNRS, Institute of Chemistry and Biochemistry (ICBMS-UMR CNRS 5246), 43 Bd du 11 Novembre 1918, 69622, Villeurbanne, France
- CPE Lyon, 43 Boulevard du 11 Novembre 1918, 69616, Villeurbanne, France
| | - Thierry Billard
- Université Lyon 1, CNRS, Institute of Chemistry and Biochemistry (ICBMS-UMR CNRS 5246), 43 Bd du 11 Novembre 1918, 69622, Villeurbanne, France
| | - Armen Panossian
- Université de Strasbourg, Université de Haute-Alsace, CNRS, ECPM, UMR 7042-LIMA, 67000, Strasbourg, France
| | - Frédéric R. Leroux
- Université de Strasbourg, Université de Haute-Alsace, CNRS, ECPM, UMR 7042-LIMA, 67000, Strasbourg, France
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18
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Difluorocarbene-derived rapid late-stage trifluoromethylation of 5-iodotriazoles for the synthesis of 18F-labeled radiotracers. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.107960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Zhu Z, Xu Y, Krishnamurti V, Koch CJ, Ispizua-Rodriguez X, Barrett C, Prakash GS. Synthesis of difluoromethylated formimidamides from primary aryl amines using TMSCF2Br as a dual C1 synthon. J Fluor Chem 2022. [DOI: 10.1016/j.jfluchem.2022.110023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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20
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Wang X, Pan S, Luo Q, Wang Q, Ni C, Hu J. Controllable Single and Double Difluoromethylene Insertions into C-Cu Bonds: Copper-Mediated Tetrafluoroethylation and Hexafluoropropylation of Aryl Iodides with TMSCF 2H and TMSCF 2Br. J Am Chem Soc 2022; 144:12202-12211. [PMID: 35786906 DOI: 10.1021/jacs.2c03104] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The selective difluoromethylene insertion into a C-Cu bond is a challenging task and is currently limited to either a single CF2 insertion into CuCF3 or double CF2 insertions into CuC6F5 (or (Z)-CF3CF = CFCu). Achieving both selective single and double CF2 insertions into the same C-Cu bond is even more difficult. Herein, highly controllable single and double CF2 insertions into CuCF2H species with a TMSCF2Br reagent have been described, affording two previously unknown fluoroalkylcopper species "Cu(CF2)nCF2H" (n = 1 and 2) independently under different reaction conditions. This work represents the first example of both single and double CF2 insertions into the same C-Cu bond in a highly selective manner. The synthetic value of the obtained "Cu(CF2)nCF2H" (n = 1 and 2) species is demonstrated by their reactions with aryl iodides, halogenation agents, and cinnamyl chloride, which enables the direct transfer of HCF2CF2 and HCF2CF2CF2 moieties into organic molecules. The key to controllable fluorocarbon chain elongation from C1 to C2 and from C1 to C3 is presumably attributed to the different reactivities of "Cu(CF2)nCF2H" species (n = 0, 1, 2 and 3) and the loading of the TMSCF2Br reagent.
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Affiliation(s)
- Xiu Wang
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Shitao Pan
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Qinyu Luo
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Qian Wang
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Chuanfa Ni
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
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21
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Zhu X, Wei J, Hu C, Xiao Q, Cai L, Wang H, Xie Y, Sheng R. Difluorocarbene‐Induced Ring‐Opening of Tetrahydrofuran with TMSCF2Br for Difluoromethoxybutylation of N‐aryl‐N‐hydroxylamines. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xinjie Zhu
- Zhejiang University College of Pharmaceutical Sciences CHINA
| | - Jun Wei
- Zhejiang University College of Pharmaceutical Sciences CHINA
| | - Chenxian Hu
- Zhejiang University College of Pharmaceutical Sciences CHINA
| | - Qitao Xiao
- Zhejiang University College of Pharmaceutical Sciences CHINA
| | - Lvtao Cai
- Zhejiang University College of Pharmaceutical Sciences CHINA
| | - Hao Wang
- Zhejiang University College of Pharmaceutical Sciences CHINA
| | - Yuanyuan Xie
- Zhejiang University of Technology Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals CHINA
| | - Rong Sheng
- Zhejiang University College of Pharmaceutical Science Zijingang CampusRoom 552,College of pharmaceutical science 310058 Hangzhou CHINA
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22
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Sap JBI, Meyer CF, Ford J, Straathof NJW, Dürr AB, Lelos MJ, Paisey SJ, Mollner TA, Hell SM, Trabanco AA, Genicot C, Am Ende CW, Paton RS, Tredwell M, Gouverneur V. [ 18F]Difluorocarbene for positron emission tomography. Nature 2022; 606:102-108. [PMID: 35344982 DOI: 10.1038/s41586-022-04669-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 03/21/2022] [Indexed: 11/09/2022]
Abstract
The advent of total-body positron emission tomography (PET) has vastly broadened the range of research and clinical applications of this powerful molecular imaging technology1. Such possibilities have accelerated progress in fluorine-18 (18F) radiochemistry with numerous methods available to 18F-label (hetero)arenes and alkanes2. However, access to 18F-difluoromethylated molecules in high molar activity is mostly an unsolved problem, despite the indispensability of the difluoromethyl group for pharmaceutical drug discovery3. Here we report a general solution by introducing carbene chemistry to the field of nuclear imaging with a [18F]difluorocarbene reagent capable of a myriad of 18F-difluoromethylation processes. In contrast to the tens of known difluorocarbene reagents, this 18F-reagent is carefully designed for facile accessibility, high molar activity and versatility. The issue of molar activity is solved using an assay examining the likelihood of isotopic dilution on variation of the electronics of the difluorocarbene precursor. Versatility is demonstrated with multiple [18F]difluorocarbene-based reactions including O-H, S-H and N-H insertions, and cross-couplings that harness the reactivity of ubiquitous functional groups such as (thio)phenols, N-heteroarenes and aryl boronic acids that are easy to install. The impact is illustrated with the labelling of highly complex and functionalized biologically relevant molecules and radiotracers.
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Affiliation(s)
- Jeroen B I Sap
- University of Oxford, Chemistry Research Laboratory, Oxford, UK
| | - Claudio F Meyer
- University of Oxford, Chemistry Research Laboratory, Oxford, UK
- Discovery Chemistry Janssen Research and Development, Toledo, Spain
| | - Joseph Ford
- University of Oxford, Chemistry Research Laboratory, Oxford, UK
| | | | | | | | - Stephen J Paisey
- Wales Research and Diagnostic PET Imaging Centre (PETIC), School of Medicine, Cardiff University, Cardiff, UK
| | - Tim A Mollner
- University of Oxford, Chemistry Research Laboratory, Oxford, UK
| | - Sandrine M Hell
- University of Oxford, Chemistry Research Laboratory, Oxford, UK
| | | | | | | | - Robert S Paton
- Department of Chemistry, Colorado State University, Fort Collins, CO, USA
| | - Matthew Tredwell
- Wales Research and Diagnostic PET Imaging Centre (PETIC), School of Medicine, Cardiff University, Cardiff, UK
- School of Chemistry, Cardiff University, Cardiff, UK
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23
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Liu R, Hu J. Synthesis of Aryl Perfluorocyclopropyl Ethers via [2 + 1] Cyclopropanation Using TMSCF 2Br Reagent. Org Lett 2022; 24:3589-3593. [PMID: 35467891 DOI: 10.1021/acs.orglett.2c00958] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aryl perfluorocyclopropyl ethers have been synthesized for the first time by [2 + 1] cyclopropanation between aryl trifluorovinyl ethers and a commercially available TMSCF2Br reagent. This cycloaddition reaction between two fluorine-containing reactants proceeds smoothly in toluene at 120 °C in the presence of a catalytic amount of n-Bu4NBr, and the reaction tolerates a variety of functional groups. A wide range of aryl trifluorovinyl ethers, easily accessible from phenols, were successfully transformed to aryl perfluorocyclopropyl ethers.
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Affiliation(s)
- Ran Liu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
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24
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Liang J, Dong L, Qian F, Kong Y, Wang M, Xu X, Shao X, Li Z. A bench-stable reagent for C-4 selective deuteriodifluoromethylation of azines. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.01.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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25
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Li J, Ye J, Zhou J, Li J, Liu D, Zhang W. RuPHOX-Ru Catalyzed Asymmetric Hydrogenation of α-Substituted Tetralones via a Dynamic Kinetic Resolution. Chem Commun (Camb) 2022; 58:4905-4908. [DOI: 10.1039/d2cc01193j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The efficient RuPHOX-Ru catalyzed asymmetric hydrogenation of α-substituted tetralones via a dynamic kinetic resolution has been achieved for the synthesis of chiral tetrahydronaphthols. The mechanism study indicated that the hydrogenation...
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26
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Sheng H, Chen Z, Li X, Su J, Song Q. Construction and transformations of 2,2-difluoro-2,3-dihydrofurans from enaminones and diflurocarbene. Org Chem Front 2022. [DOI: 10.1039/d2qo00468b] [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
A simple and efficient construction of 2-difluoro-2,3-dihydrofurans was reported, which features metal-free, additive-free, broad functional group tolerance and readily accessible starting materials. It is worth mentioning that this type of...
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27
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Liu A, Ni C, Xie Q, Hu J. TMSCF
2
Br‐Enabled Fluorination–Aminocarbonylation of Aldehydes: Modular Access to α‐Fluoroamides. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202115467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- An Liu
- Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Ling-Ling Road Shanghai 200032 China
| | - Chuanfa Ni
- Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Ling-Ling Road Shanghai 200032 China
| | - Qiqiang Xie
- Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Ling-Ling Road Shanghai 200032 China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Ling-Ling Road Shanghai 200032 China
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28
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Liu A, Ni C, Xie Q, Hu J. TMSCF 2 Br-Enabled Fluorination-Aminocarbonylation of Aldehydes: Modular Access to α-Fluoroamides. Angew Chem Int Ed Engl 2021; 61:e202115467. [PMID: 34919312 DOI: 10.1002/anie.202115467] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Indexed: 01/03/2023]
Abstract
A protocol for the modular assembly of the α-fluoroamide motif has been developed, which provides a practical method for the efficient synthesis of structurally diverse α-fluoroamides from easily available aldehydes and tertiary amines through a three-component fluorination-aminocarbonylation process. The key to the success of this process is taking advantage of the multiple roles of the unique difluorocarbene reagent TMSCF2 Br (TMS=trimethylsilyl). The mechanism of the process involves the 1,2-fluorine and oxygen migrations of the in situ formed TMS-protected α-aminodifluoromethyl carbinol intermediates, which represents a new type of deoxyfluorination reaction.
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Affiliation(s)
- An Liu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Chuanfa Ni
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Qiqiang Xie
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, China
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29
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Sheng H, Su J, Li X, Li X, Song Q. Double Capture of Difluorocarbene by 2-Aminostyrenes Enables the Construction of 3-(2,2-Difluoroethyl)-2-fluoroindoles. Org Lett 2021; 23:7781-7786. [PMID: 34617770 DOI: 10.1021/acs.orglett.1c02816] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report herein an efficient strategy to construct 3-(2,2-difluoroethyl)-2-fluoroindoles from activated o-aminostyrenes with ethyl bromodi-fluoroacetate as a difluorocarbene source. Through double capture of a difluorocarbene, two different types of fluorine motifs are incorporated into the products with simultaneous construction of one C-N and two C-C bonds, without the need for transition metals. This reaction features high efficiency and excellent functional group compatibility and has great potential in the late-stage modifications of pharmaceutical molecules and natural products.
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Affiliation(s)
- Heyun Sheng
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
| | - Jianke Su
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
| | - Xin Li
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
| | - Xue Li
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
| | - Qiuling Song
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China.,Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China.,State Key Laboratory of Organometallic Chemistry and Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
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30
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Zhang R, Li Q, Xie Q, Ni C, Hu J. Difluorocarbene-Induced Ring-Opening Difluoromethylation-Halogenation of Cyclic (Thio)Ethers with TMSCF 2 X (X=Br, Cl)*. Chemistry 2021; 27:17773-17779. [PMID: 34648215 DOI: 10.1002/chem.202103428] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Indexed: 01/14/2023]
Abstract
The ring-opening difluoromethylation-halogenation of cyclic (thio)ethers is reported through a simple strategy relying on carbon-chalcogen bond activation with difluorocarbene. The reaction proceeds through in situ protonation of the previously little-known difluoromethylene oxonium or sulfonium ylide intermediate followed by ring-opening with halide ion to afford halogenated acyclic difluoromethyl (thio)ethers that can then be employed for further elaboration. TMSCF2 X (X=Br, Cl) are unique reagents to achieve this synthetic purpose, which serve as both the difluorocarbene source and the halide ion source.
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Affiliation(s)
- Rongyi Zhang
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, P. R. China.,School of Physical Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai, 201210, P. R. China
| | - Qigang Li
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, P. R. China
| | - Qiqiang Xie
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, P. R. China
| | - Chuanfa Ni
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, P. R. China
| | - Jinbo Hu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai, 200032, P. R. China.,School of Physical Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai, 201210, P. R. China
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31
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Tong C, Xu X, Qing F. Nucleophilic and Radical Heptafluoroisopropoxylation with Redox‐Active Reagents. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Chao‐Lai Tong
- Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Science 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 Science Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China
| | - Feng‐Ling Qing
- Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Science Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China
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32
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Tong CL, Xu XH, Qing FL. Nucleophilic and Radical Heptafluoroisopropoxylation with Redox-Active Reagents. Angew Chem Int Ed Engl 2021; 60:22915-22924. [PMID: 34414643 DOI: 10.1002/anie.202109572] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 08/12/2021] [Indexed: 11/05/2022]
Abstract
The heptafluoroisopropyl group (CF(CF3 )2 ) is prevalent in pharmaceuticals and agrichemicals. However, heptafluoroisopropoxylated (OCF(CF3 )2 ) compounds remain largely underexplored, presumably due to the lack of efficient access to these compounds. Herein, we disclose the practical and efficient heptafluoroisopropoxylation reactions through the invention of a series of redox-active N-OCF(CF3 )2 reagents. These reagents were readily prepared from the oxidative heptafluoroisopropylation of hydroxylamines with AgCF(CF3 )2 . The substitutions on the nitrogen atom significantly affected the properties and reactivities of N-OCF(CF3 )2 reagents. Accordingly, two types of N-OCF(CF3 )2 reagents including N-OCF(CF3 )2 phthalimide A and N-OCF(CF3 )2 benzotriazolium salt O' were used as OCF(CF3 )2 anion and radical precursors, respectively. This protocol enables the direct heptafluoroisopropoxylation of a range of substrates, delivering the corresponding products in moderate to excellent yields.
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Affiliation(s)
- Chao-Lai Tong
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Science, 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 Science, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, China
| | - Feng-Ling Qing
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Science, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, China
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33
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Loison A, Toulgoat F, Billard T, Hanquet G, Panossian A, Leroux FR. Recent synthetic methods towards the –OCHF2 moiety. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132458] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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34
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Regio- and chemoselectivity in S- and O- difluoromethylation reactions using diethyl (bromodifluoromethyl)phosphonate. J Fluor Chem 2021. [DOI: 10.1016/j.jfluchem.2021.109867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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35
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Zhu Z, Krishnamurti V, Ispizua-Rodriguez X, Barrett C, Prakash GKS. Chemoselective N- and O-Difluoromethylation of 2-Pyridones, Isoquinolinones, and Quinolinones with TMSCF 2Br. Org Lett 2021; 23:6494-6498. [PMID: 34344153 DOI: 10.1021/acs.orglett.1c02305] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An operationally simple protocol for direct N- and O-difluoromethylation of 2-pyridones, quinolinones, and isoquinolinones using commercially available TMSCF2Br is disclosed. The chemoselectivity is modulated by simple variations in temperature, solvent, and strength of the base. Diverse, synthetically relevant functional groups are tolerated, including functional groups that have reported reactivity with TMSCF2Br. Gram-scale reactions to prepare both N- and O-difluoromethyl compounds are included.
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Affiliation(s)
- Ziyue Zhu
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Vinayak Krishnamurti
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Xanath Ispizua-Rodriguez
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - Colby Barrett
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
| | - G K Surya Prakash
- Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661, United States
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36
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Liang J, Wang G, Dong L, Pang X, Qin J, Xu X, Shao X, Li Z. CF 2DSO 2Na: An Effective Precursor Reagent for Deuteriodifluoromethylthiolation and Deuteriodifluoromethylation. Org Lett 2021; 23:5545-5548. [PMID: 34231355 DOI: 10.1021/acs.orglett.1c01882] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Deuteriodifluoromethythio (SCF2D) and deuteriodifluoromethyl (CF2D) are important functional groups in pharmaceutical and agrochemical compounds, and the introduction of these functional groups remains a challenging. We herein report a robust reagent for deuteriodifluoromethylthiolation and deuteriodifluoromethylation. Its potentials were successfully showcased by deuteriodifluoromethylation and deuteriodifluoromethylthiolation of indoles with high-level deuterium incorporation. The reagent also has potential for deuteriodifluoromethylation and deuteriodifluoromethylthiolation of wide range of other natural or synthetic bioactive molecules.
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Affiliation(s)
- Junqing Liang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Gangao Wang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Lefeng Dong
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Xiwen Pang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Jiawei Qin
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaoyong Xu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Xusheng Shao
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Zhong Li
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
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37
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Britton R, Gouverneur V, Lin JH, Meanwell M, Ni C, Pupo G, Xiao JC, Hu J. Contemporary synthetic strategies in organofluorine chemistry. ACTA ACUST UNITED AC 2021. [DOI: 10.1038/s43586-021-00042-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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38
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Fu WC, MacQueen PM, Jamison TF. Continuous flow strategies for using fluorinated greenhouse gases in fluoroalkylations. Chem Soc Rev 2021; 50:7378-7394. [PMID: 34018500 DOI: 10.1039/d0cs00670j] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Large quantities of fluorinated gases are generated as intermediates or byproducts from fluorinated polymer production annually, and they are effective ozone depleting substances or greenhouse gases. On the other hand, the incorporation of fluoroalkyl groups into drug molecules or bioactive compounds has been shown to enhance biological properties such as the bioavailability, binding selectivity, and metabolic stability. Extraction of fluoroalkyl sources, including trifluoromethyl and difluoromethyl groups, from the fluorinated gases is highly desirable, yet challenging under regular batch reaction conditions. Flow chemistry is an emerging and promising technique to address long-standing challenges in gas-liquid batch reactions such as insufficient interfacial contact and scalability issues. In this review, we highlight recent advances in continuous flow strategies toward enabling the use of fluorinated greenhouse gases in organic synthesis.
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Affiliation(s)
- Wai Chung Fu
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Preston M MacQueen
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. and Department of Research and Development, MilliporeSigma (a division of Merck KGaA), 6000 N. Teutonia Avenue, Milwaukee, WI 53209, USA
| | - Timothy F Jamison
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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39
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Wang Y, Wang S, Zhang C, Zhao T, Hu Y, Zhang M, Chen P, Fu Y. Highly Selective Difluoromethylations of β-Keto Amides with TMSCF2Br under Mild Conditions. Synlett 2021. [DOI: 10.1055/a-1507-5878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractWithout employing any transition metal and other additives, efficient methods for selective difluoromethylations of β-keto amides with TMSCF2Br reagent have been developed under mild conditions. This protocol allows a convenient access to various α-difluoromethyl β-keto amides with excellent yields (up to 93%) and high carbon/oxygen (C/O) regioselectivities (up to 99:1). The C/O selectivity of β-keto amides could be easily reversed and controlled by simply changing the base. This protocol can be easily scaled-up and the C-difluoromethylation product could be reduced into CF2H-containing amino alcohol derivatives. Moreover, the first enantioselective electrophilic difluoromethylation of β-keto amides has been achieved by phase-transfer catalysis.
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40
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Wang Y, Wang S, Qiu P, Fang L, Wang K, Zhang Y, Zhang C, Zhao T. Asymmetric α-electrophilic difluoromethylation of β-keto esters by phase transfer catalysis. Org Biomol Chem 2021; 19:4788-4795. [PMID: 33982742 DOI: 10.1039/d1ob00511a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
An efficient and enantioselective α-electrophilic difluoromethylation of β-keto esters has been achieved by phase-transfer catalysis. This procedure is applicable to different kinds of β-keto esters with a series of cinchona-derived C-2' aryl-substituted phase-transfer catalysts. The reaction gives the corresponding products in good enantioselectivities (up to 83% ee) and yields (up to 92%) with high C/O regioselectivities (up to 98 : 2). Moreover, the C/O selectivity of β-keto esters could be easily reversed and controlled. This asymmetric difluoromethylation provided a novel and efficient way for introducing chiral C-CF2H groups.
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Affiliation(s)
- Yakun Wang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Shuaifei Wang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Peiyong Qiu
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Lizhen Fang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Ke Wang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Yawei Zhang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Conghui Zhang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
| | - Ting Zhao
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China.
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41
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Peng L, Wang H, Guo C. Copper-Catalyzed Enantioselective Difluoromethylation of Amino Acids via Difluorocarbene. J Am Chem Soc 2021; 143:6376-6381. [PMID: 33900748 DOI: 10.1021/jacs.1c02697] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Difluoromethyl amino acids (DFAA) exhibit intriguing biological properties, making them highly desirable motifs in agrochemical and pharmaceutical science. However, stereochemical control of direct difluoromethyl transformation via the difluorocarbene species has not been demonstrated. Here we describe an efficient copper-catalyzed asymmetric difluoromethylation reaction that systematically delivers chiral DFAA as rationally designed mechanism-based inhibitors of PLP-dependent amino acid decarboxylases. The reaction employs difluoromonochloromethane, an abundant raw material, as the direct precursor of difluorocarbene species, enabling the unprecedentedly direct conversion of amino esters into corresponding valuable DFAA products in good yields with excellent enantioselectivities. This de novo synthesis creates opportunities to integrate an asymmetric catalytic platform for the preparation of diverse libraries of biologically important DFAA derivatives and will support efforts in both drug discovery and development.
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Affiliation(s)
- Lingzi Peng
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Hongyi Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Chang Guo
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China
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42
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Jia Y, Yuan Y, Huang J, Jiang ZX, Yang Z. Synthesis of Difluorinated Heterocyclics through Metal-Free [8+1] and [4+1] Cycloaddition of Difluorocarbene. Org Lett 2021; 23:2670-2675. [PMID: 33724045 DOI: 10.1021/acs.orglett.1c00577] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
With Ph3P+CF2COO- or TMSCF2Br as the difluorocarbene sources, a facile metal-free cycloaddition between heteroconjugated alkenes and difluorocarbene was developed for the highly convergent synthesis of novel difluorinated heterocyclics, including gem-difluorinated azetidines and 2,3-dihydrobenzofurans. The cycloaddition features high reactivity and regioselectivity, as well as good tolerance of various electron-donating or electron-withdrawing substituents on azaheptafulvenes and o-quinone methides.
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Affiliation(s)
- Yimin Jia
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Yuan Yuan
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Jinfeng Huang
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Zhong-Xing Jiang
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Zhigang Yang
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
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43
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Okamura T, Koyamada K, Kanazawa J, Miyamoto K, Iwabuchi Y, Uchiyama M, Kanoh N. Synthetic Access to gem-Difluoropropargyl Vinyl Ethers and Their Application to Propargyl Claisen Rearrangement. J Org Chem 2021; 86:1911-1924. [PMID: 33284629 DOI: 10.1021/acs.joc.0c01777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
With the increasing importance of fluorine to medicinal chemistry and other areas, methods to access various fluorinated compounds are needed. Herein, we report the synthesis of difluoropropargyl vinyl ethers from ketones and aldehydes using difluoropropargyl bromide dicobalt complexes. We applied difluoropropargyl vinyl ethers to the synthesis of difluorodienone or difluoroallene under thermal conditions and trifluoro-pyran under acid-catalyzed conditions.
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Affiliation(s)
- Toshitaka Okamura
- School of Pharmacy and Pharmaceutical Sciences, and Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
| | - Kenta Koyamada
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Junichiro Kanazawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazunori Miyamoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoshiharu Iwabuchi
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Masanobu Uchiyama
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan, Cluster of Pioneering Research (CPR), Advanced Elements Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan, and Research Initiative for Supra-Materials (RISM), Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan
| | - Naoki Kanoh
- School of Pharmacy and Pharmaceutical Sciences, and Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
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44
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Chen D, Fan Z, Huang L, Gao K, Xiao P, Ni C, Hu J. TMSCFX 2 (X = Cl, Br) as halofluorocarbene sources for the synthesis of halofluorocyclopropanes. Chem Commun (Camb) 2021; 57:319-322. [PMID: 33326515 DOI: 10.1039/d0cc06004f] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
TMSCFX2 (X = Cl, Br; TMS = trimethylsilyl) have been developed as halofluorocarbene (CFX, X = Cl, Br) precursors for [2+1] cyclopropanation with alkenes. Structurally diverse halofluorocyclopropanes were obtained in good to excellent yields. It was found that the reactivity order of the three halofluorocarbene reagents (TMSCF2Br, TMSCFCl2, and TMSCFBr2) in halofluorocyclopropanation with 1,1-diphenylethylene can be very different under different reaction conditions.
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Affiliation(s)
- Dingben Chen
- Key Laboratory of Organofluorine 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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45
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Sap JBI, Meyer CF, Straathof NJW, Iwumene N, am Ende CW, Trabanco AA, Gouverneur V. Late-stage difluoromethylation: concepts, developments and perspective. Chem Soc Rev 2021; 50:8214-8247. [DOI: 10.1039/d1cs00360g] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review describes the conceptual advances that have led to the multiple difluoromethylation processes making use of well-defined CF2H sources.
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Affiliation(s)
- Jeroen B. I. Sap
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Claudio F. Meyer
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Natan J. W. Straathof
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Ndidi Iwumene
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
| | - Christopher W. am Ende
- Pfizer Inc
- Medicine Design, Eastern Point Road, Groton, Connecticut 06340, and 1 Portland Street
- Cambridge
- USA
| | | | - Véronique Gouverneur
- Chemistry Research Laboratory
- Department of Chemistry
- Oxford University
- OX1 3TA Oxford
- UK
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46
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Difluoromethylation of alcohols with TMSCF2Br in water: A new insight into the generation and reactions of difluorocarbene in a two-phase system. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131676] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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47
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Hou X, Zhou S, Li Y, Guo M, Zhao W, Tang X, Wang G. Synthesis of Indolizines from Pyridinium Salts and Ethyl Bromodifluoroacetate. Org Lett 2020; 22:9313-9318. [DOI: 10.1021/acs.orglett.0c03540] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Xiaoya Hou
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Sen Zhou
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Yuli Li
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Minjie Guo
- Institute for Molecular Design and Synthesis, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, P. R. China
| | - Wentao Zhao
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Xiangyang Tang
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Guangwei Wang
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
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48
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Su J, Ma X, Ou Z, Song Q. Deconstructive Functionalizations of Unstrained Carbon-Nitrogen Cleavage Enabled by Difluorocarbene. ACS CENTRAL SCIENCE 2020; 6:1819-1826. [PMID: 33145418 PMCID: PMC7596867 DOI: 10.1021/acscentsci.0c00779] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Indexed: 05/03/2023]
Abstract
Transition-metal- or oxidant-promoted deconstructive functionalizations of noncyclic carbon-nitrogen bonds are well established, usually only leaving one moiety functionalized toward the final product. In contrast, concomitant C- and N-functionalizations via the unstrained C(sp3)-N bond under metal- and oxidant-free conditions are very rare, which would favorably confer versatility and product diversity. Disclosed herein is the first difluorocarbene-induced deconstructive functionalizations embodying successive C(sp3)-N bond cleavage of cyclic amines and synchronous functionalization of both constituent atoms which would be preserved in the eventual molecular outputs under transition-metal-free and oxidant-free conditions. Correspondent access to deuterated formamides with ample isotopic incorporation was demonstrated by a switch to heavy water which is conceivably useful in pharmaceutical sciences. The current strategy remarkably administers a very convenient, operationally simple and novel method toward molecular diversity from readily available starting materials. Therefore, we project that these findings would be of broad interest to research endeavors encompassing fluorine chemistry, carbene chemistry, C-N bond activation, as well as medicinal chemistry.
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Affiliation(s)
- Jianke Su
- Institute of Next
Generation Matter Transformation, College of Material Sciences &
Engineering at Huaqiao University, 668 Jimei Boulevard, Xiamen, Fujian 361021, China
| | - Xingxing Ma
- Institute of Next
Generation Matter Transformation, College of Material Sciences &
Engineering at Huaqiao University, 668 Jimei Boulevard, Xiamen, Fujian 361021, China
| | - Zongliang Ou
- Institute of Next
Generation Matter Transformation, College of Material Sciences &
Engineering at Huaqiao University, 668 Jimei Boulevard, Xiamen, Fujian 361021, China
| | - Qiuling Song
- Institute of Next
Generation Matter Transformation, College of Material Sciences &
Engineering at Huaqiao University, 668 Jimei Boulevard, Xiamen, Fujian 361021, China
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at
Fuzhou University, Fuzhou, Fujian 350108, China
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49
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Huang H, Li H, Cordier M, Soulé J, Doucet H. Pd‐Catalyzed Direct Arylations of Heteroarenes with Polyfluoroalkoxy‐Substituted Bromobenzenes. European J Org Chem 2020. [DOI: 10.1002/ejoc.202001028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | - Haoran Li
- CNRS, ISCR‐UMR 6226 Univ Rennes 35000 Rennes France
| | | | | | - Henri Doucet
- CNRS, ISCR‐UMR 6226 Univ Rennes 35000 Rennes France
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50
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Xu Z, Zhang W, Lin J, Jin C, Xiao J. Pd‐Catalyzed
Transfer of Difluorocarbene for Three Component
Cross‐Coupling
†. CHINESE J CHEM 2020. [DOI: 10.1002/cjoc.202000297] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Zhi‐Wei Xu
- Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi Hubei 435002 China
- 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 China
| | - Wei Zhang
- 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 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 Shanghai 200032 China
| | - Chuan‐Ming Jin
- Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi Hubei 435002 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 Shanghai 200032 China
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