1
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Maas LM, Fasting C, Voßnacker P, Limberg N, Golz P, Müller C, Riedel S, Hopkinson MN. Catalyst-Free Trifluoromethoxylation of Silyl Enol Ethers and Allyl Silanes with Bis(trifluoromethyl)peroxide. Angew Chem Int Ed Engl 2024; 63:e202317770. [PMID: 38131450 DOI: 10.1002/anie.202317770] [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: 11/21/2023] [Revised: 12/19/2023] [Accepted: 12/21/2023] [Indexed: 12/23/2023]
Abstract
Radical trifluoromethoxylation is an attractive approach to prepare compounds featuring the important OCF3 group, however most existing methods have focused on aromatic substrates. Here, we report novel methodologies with alkenyl substrates employing bis(trifluoromethyl)peroxide (BTMP) as a practical and comparatively atom economical trifluoromethoxylating reagent. With silyl enol ether substrates, switching reaction solvent allows for the synthesis of either α-(trifluoromethoxy)ketone products or unprecedented alkenyl-OCF3 species. Furthermore, allyl silanes have been employed as substrates for the first time, affording allyl(trifluoromethyl)ether products in good yields. In each case, the methods operate at room temperature without large excesses of the alkene substrate while, in contrast to previous radical trifluoromethoxylation reactions, no catalyst, light or other activators are required.
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Affiliation(s)
- Lilian M Maas
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
- School of Natural and Environmental Sciences, Newcastle University Bedson Building, Newcastle upon Tyne, NE1 7RU, UK
| | - Carlo Fasting
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
| | - Patrick Voßnacker
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
| | - Niklas Limberg
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
| | - Paul Golz
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
| | - Carsten Müller
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
| | - Sebastian Riedel
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
| | - Matthew N Hopkinson
- Institut für Chemie und Biochemie-Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34/36, 14195, Berlin, Germany
- School of Natural and Environmental Sciences, Newcastle University Bedson Building, Newcastle upon Tyne, NE1 7RU, UK
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2
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Deng Z, Meng L, Bing X, Niu S, Zhang X, Peng J, Luan YX, Chen L, Tang P. Silver-Enabled Dearomative Trifluoromethoxylation of Indoles. J Am Chem Soc 2024; 146:2325-2332. [PMID: 38232384 DOI: 10.1021/jacs.3c11653] [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
The only known method for the dearomative trifluoromethoxylation of indoles is preliminary, with only one substrate successfully undergoing the reaction. In this study, we not only developed a broadly applicable method for indole dearomative trifluoromethoxylation but also achieved divergent trifluoromethoxylation by fine-tuning the reaction conditions. Under optimized conditions, with a silver salt and an easily handled OCF3 reagent, various indoles smoothly underwent dearomatization to afford a diverse array of ditrifluoromethoxylated indolines in 50-84% isolated yields with up to 37:1 diastereoselectivity, and fluorinated trifluoromethoxylated indolines were obtained with exclusive trans selectivity. In addition, the reaction conditions were compatible with other heteroaromatic rings as well as styrene moieties.
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Affiliation(s)
- Zhijie Deng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Lingduan Meng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiao Bing
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shaoxiong Niu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiaofeng Zhang
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, China
| | - Junqin Peng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yu-Xin Luan
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Li Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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3
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Hernández-Ruiz R, Gómez-Gil S, Pedrosa MR, Suárez-Pantiga S, Sanz R. Direct synthesis of haloaromatics from nitroarenes via a sequential one-pot Mo-catalyzed reduction/Sandmeyer reaction. Org Biomol Chem 2023; 21:7791-7798. [PMID: 37706648 DOI: 10.1039/d3ob01187a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
Herein, we report the direct synthesis of a wide variety of functionalized aromatic bromides, chlorides, iodides, and fluorides from nitroarenes in a sequential one-pot operation. This protocol is based on an air- and moisture-tolerant dioxomolybdenum-catalyzed reduction of nitroaromatics, employing pinacol as a reducing agent, which enables subsequent diazotization and halogenation steps. This methodology represents a step-economical, practical, and alternative procedure for synthesizing haloaromatics directly from nitroaromatics.
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Affiliation(s)
- Raquel Hernández-Ruiz
- Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001 Burgos, Spain.
| | - Sara Gómez-Gil
- Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001 Burgos, Spain.
| | - María R Pedrosa
- Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001 Burgos, Spain.
| | - Samuel Suárez-Pantiga
- Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001 Burgos, Spain.
| | - Roberto Sanz
- Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001 Burgos, Spain.
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4
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Winter M, Ellwanger MA, Limberg N, Pérez-Bitrián A, Voßnacker P, Steinhauer S, Riedel S. Reactivity of [AuF 3 (SIMes)]: Pathway to Unprecedented Structural Motifs. Chemistry 2023; 29:e202301684. [PMID: 37340637 DOI: 10.1002/chem.202301684] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/20/2023] [Accepted: 06/20/2023] [Indexed: 06/22/2023]
Abstract
We report on a comprehensive reactivity study starting from [AuF3 (SIMes)] to synthesize different motifs of monomeric gold(III) fluorides. A plethora of different ligands has been introduced in a mono-substitution yielding trans-[AuF2 X(SIMes)] including alkynido, cyanido, azido, and a set of perfluoroalkoxido complexes. The latter were better accomplished via use of perfluorinated carbonyl-bearing molecules, which is unprecedented in gold chemistry. In case of the cyanide and azide, triple substitution gave rise to the corresponding [AuX3 (SIMes)] complexes. Comparison of the chemical shift of the carbene carbon atom in the 13 C{1 H} NMR spectrum, the calculated SIMes affinity and the Au-C bond length in the solid state with related literature-known complexes yields a classification of trans-influences for a variety of ligands attached to the gold center. Therein, the mixed fluorido perfluoroalkoxido complexes have a similar SIMes affinity to AuF3 with a very low Gibbs energy of formation when using the perfluoro carbonyl route.
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Affiliation(s)
- Marlon Winter
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
| | - Mathias A Ellwanger
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, OX1 3QR, Oxford, UK
| | - Niklas Limberg
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
| | - Alberto Pérez-Bitrián
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
| | - Patrick Voßnacker
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
| | - Simon Steinhauer
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
| | - Sebastian Riedel
- Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195, Berlin, Germany
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5
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Chen LY, Pan PF, Lin JH, Jin CM, Xiao JC. Tf 2O as a CF 3 Source for the Synthesis of Trifluoromethoxylation Reagent nC 4F 9SO 3CF 3. J Org Chem 2023. [PMID: 36763542 DOI: 10.1021/acs.joc.2c03018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Described herein is the convenient synthesis of an efficient trifluoromethoxylation reagent, nC4F9SO3CF3, by using cheap and widely available reagents and without the need of any tedious column chromatography purification procedure.
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Affiliation(s)
- Ling-Ying Chen
- Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 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
| | - Peng-Fei Pan
- 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.,Department of Chemistry, Innovative Drug Research Center, Shanghai University, Shanghai 200444, China
| | - Chuan-Ming Jin
- Hubei Key Laboratory of Pollutant Analysis and Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 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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6
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Ran LY, Ding X, Yan XP, Zhang CP. Divergent dehydroxyfluorination and carbonation of alcohols with trifluoromethyl trifluoromethanesulfonate. Org Biomol Chem 2023; 21:1235-1241. [PMID: 36633208 DOI: 10.1039/d2ob02028a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Preparation of alkyl fluorides and carbonates via divergent dehydroxyfluorination and carbonation of alcohols with trifluoromethyl trifluoromethanesulfonate (CF3SO2OCF3) is described. The reactions performed with BTMG in THF provided alkyl fluorides in good yields, whereas those of two different alcohols with Et3N in DCM formed asymmetric carbonates in moderate to excellent yields. CF3SO2OCF3 was demonstrated to be either a "F" or a "CO" reagent in the reactions by changing the base, allowing the selective construction of alkyl fluorides and carbonates from the corresponding alcohols with high efficiency. Notably, the fluorine-containing asymmetric carbonates that are difficult to synthesize by other methods were comprehensively prepared by this method, which would have great application potential in both academic and industrial fields.
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Affiliation(s)
- Long-Yu Ran
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China.
| | - Xue Ding
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China.
| | - Xue-Ping Yan
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China.
| | - Cheng-Pan Zhang
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China.
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7
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Barata‐Vallejo S, Bonesi SM, Postigo A. Trifluoromethoxylation Reactions of (Hetero) arenes, Olefinic Systems and Aliphatic Saturated Substrates. Chemistry 2022; 28:e202201776. [DOI: 10.1002/chem.202201776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Sebastian Barata‐Vallejo
- Departamento de Ciencias Químicas Facultad de Farmacia y Bioquímica Universidad de Buenos Aires Junin 954 CP 1113 Buenos Aires Argentina
- Istituto per la Sintesi Organica e la Fotoreattività ISOF Consiglio Nazionale delle Ricerche Via P. Gobetti 101 40129 Bologna Italy
| | - Sergio M. Bonesi
- Departamento de Química Orgánica Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Ciudad Universitaria C1428EGA Buenos Aires Argentina
| | - Al Postigo
- Departamento de Ciencias Químicas Facultad de Farmacia y Bioquímica Universidad de Buenos Aires Junin 954 CP 1113 Buenos Aires Argentina
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8
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Jakubczyk M, Mkrtchyan S, Shkoor M, Lanka S, Budzák Š, Iliaš M, Skoršepa M, Iaroshenko VO. Mechanochemical Conversion of Aromatic Amines to Aryl Trifluoromethyl Ethers. J Am Chem Soc 2022; 144:10438-10445. [PMID: 35652785 PMCID: PMC9204773 DOI: 10.1021/jacs.2c02611] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
![]()
Increased interest
in the trifluoromethoxy group in organic synthesis
and medicinal chemistry has induced a demand for new, selective, general,
and faster methods applicable to natural products and highly functionalized
compounds at a later stage of hit-to-lead campaigns. Applying pyrylium
tetrafluoroborate, we have developed a mechanochemical protocol to
selectively substitute the aromatic amino group with the OCF3 functionality. The scope of our method includes 31 examples of ring-substituted
anilines, including amides and sulfonamides. Expected SNAr products were obtained in excellent yields. The presented concise
method opens a pathway to new chemical spaces for the pharmaceutical
industry.
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Affiliation(s)
- Michał Jakubczyk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznań 61-704, Poland
| | - Satenik Mkrtchyan
- Laboratory of Homogeneous Catalysis and Molecular Design at the Center of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, Łodź PL-90-363, Poland
| | - Mohanad Shkoor
- Department of Chemistry and Earth Sciences, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Suneel Lanka
- Lodz University of Technology, Stefana Żeromskiego 116, Lodz 90-924, Poland
| | - Šimon Budzák
- Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, Banská Bystrica 97401, Slovakia
| | - Miroslav Iliaš
- Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, Banská Bystrica 97401, Slovakia
| | - Marek Skoršepa
- Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, Banská Bystrica 97401, Slovakia
| | - Viktor O Iaroshenko
- Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, Banská Bystrica 97401, Slovakia.,Department of Chemistry, University of Helsinki, A.I. Virtasen aukio 1, Helsinki 00014, Finland
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9
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Ouyang Y, Xu X, Qing F. Electrochemical Trifluoromethoxylation of (Hetero)aromatics with a Trifluoromethyl Source and Oxygen. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114048] [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)
- Yao Ouyang
- 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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10
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Abstract
We disclose a silver-catalyzed trifluoromethoxylation of N-tosyl aziridines with trifluoromethyl arylsulfonate. The protocol is characterized by its mild conditions, simple operations, and good chemo- and regioselectivity. In addition, the trifluoromethoxylation of trisubstituted aziridines could construct C-OCF3 quaternary centers exclusively, which is quite rare. This method unlocks a new catalytic blueprint for accessing β-trifluoromethoxylated amines, which could be important building blocks in synthetic chemistry.
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Affiliation(s)
- Jingrui Xin
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiangyu Deng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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11
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Tang Y, Yu B. A Mild Heteroatom (O-, N-, and S-) Methylation Protocol Using Trimethyl Phosphate (TMP)–Ca(OH)2Combination. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/a-1731-3852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractA mild heteroatom methylation protocol using trimethyl phosphate (TMP)–Ca(OH)2 combination has been developed, which proceeds in DMF, or water, or under neat conditions, at 80 °C or at room temperature. A series of O-, N-, and S-nucleophiles, including phenols, sulfonamides, N-heterocycles, such as 9H-carbazole, indole derivatives, and 1,8-naphthalimide, and aryl/alkyl thiols, are suitable substrates for this protocol. The high efficiency, operational simplicity, scalability, cost-efficiency, and environmentally friendly nature of this protocol make it an attractive alternative to the conventional base-promoted heteroatom methylation procedures.
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12
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Abstract
This review provides a short summary of the traditional methods for synthesis of CF3-O-containing compounds, followed by a critical overview of known trifluoromethoxylating reagents, focusing on their preparation, synthetic generality and limitations.
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13
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Ouyang Y, Xu XH, Qing FL. Electrochemical Trifluoromethoxylation of (Hetero)aromatics with a Trifluoromethyl Source and Oxygen. Angew Chem Int Ed Engl 2021; 61:e202114048. [PMID: 34755434 DOI: 10.1002/anie.202114048] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/08/2021] [Indexed: 11/08/2022]
Abstract
Trifluoromethoxylated aromatics (ArOCF3 ) are valuable structural motifs in the area of drug discovery due to the enhancement of their desired physicochemical properties upon the introduction of the trifluoromethoxy group (CF3 O). Although significant progress has been made recently in the introduction of CF3 O group into aromatics, current methods either require the use of expensive trifluoromethoxylation reagents or require harsh reaction conditions. We present a conceptually new and operationally simple protocol for the direct C-H trifluoromethoxylation of (hetero)aromatics by the combination of the readily available trifluoromethylating reagent and oxygen under electrochemical reaction conditions. This reaction proceeds through the initial generation of CF3 radical followed by conversion to CF3 O radical, addition to (hetero)aromatics and rearomatization. The utility of this electrochemical trifluoromethoxylation is illustrated by the direct incorporation of CF3 O group into a variety of (hetero)aromatics as well as bio-relevant molecules.
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Affiliation(s)
- Yao Ouyang
- 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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14
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Yang YM, Yan W, Hu HW, Luo Y, Tang ZY, Luo Z. Photoinduced Acetylation of Anilines under Aqueous and Catalyst-Free Conditions. J Org Chem 2021; 86:12344-12353. [PMID: 34370464 DOI: 10.1021/acs.joc.1c01290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A green and efficient visible-light induced functionalization of anilines under mild conditions has been reported. Utilizing nontoxic, cost-effective, and water-soluble diacetyl as photosensitizer and acetylating reagent, and water as the solvent, a variety of anilines were converted into the corresponding aryl ketones, iodides, and bromides. With advantages of environmentally friendly conditions, simple operation, broad substrate scope, and functional group tolerance, this reaction represents a valuable method in organic synthesis.
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Affiliation(s)
- Yu-Ming Yang
- School of Pharmaceutical Science (Shenzhen), Sun Yat-sen University, Guangzhou 510275, China.,College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
| | - Wei Yan
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
| | - Han-Wei Hu
- School of Pharmaceutical Science (Shenzhen), Sun Yat-sen University, Guangzhou 510275, China
| | - Yimin Luo
- School of Material, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhen-Yu Tang
- School of Pharmaceutical Science (Shenzhen), Sun Yat-sen University, Guangzhou 510275, China.,College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
| | - Zhuangzhu Luo
- School of Material, Sun Yat-sen University, Guangzhou 510275, China
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15
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Lu Z, Kumon T, Hammond GB, Umemoto T. Trifluoromethyl Nonaflate: A Practical Trifluoromethoxylating Reagent and its Application to the Regio‐ and Stereoselective Synthesis of Trifluoromethoxylated Alkenes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202104975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zhichao Lu
- Department of Chemistry University of Louisville Louisville KY 40292 USA
| | - Tatsuya Kumon
- Faculty of Molecular Chemistry and Engineering Kyoto Institute of Technology Matsugasaki, Sakyo-ku Kyoto 606-8585 Japan
| | - Gerald B. Hammond
- Department of Chemistry University of Louisville Louisville KY 40292 USA
| | - Teruo Umemoto
- Department of Chemistry University of Louisville Louisville KY 40292 USA
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16
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Lu Z, Kumon T, Hammond GB, Umemoto T. Trifluoromethyl Nonaflate: A Practical Trifluoromethoxylating Reagent and its Application to the Regio- and Stereoselective Synthesis of Trifluoromethoxylated Alkenes. Angew Chem Int Ed Engl 2021; 60:16171-16177. [PMID: 34010513 PMCID: PMC8260458 DOI: 10.1002/anie.202104975] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Indexed: 01/18/2023]
Abstract
The trifluoromethoxy group has elicited much interest among drug and agrochemical discovery teams because of its unique properties. We developed trifluoromethyl nonafluorobutanesulfonate (nonaflate), TFNf, an easy-to-handle, bench-stable, reactive, and scalable trifluoromethoxylating reagent. TFNf is easily and safely prepared in a simple process in large scale and the nonaflyl part of TFNf can easily be recovered as nonaflyl fluoride after usage and recycled. The synthetic potency of TFNf was showcased with the underexplored synthesis of various trifluoromethoxylated alkenes, through a high regio- and stereoselective hydro(halo)trifluoromethoxylation of alkyne derivatives such as haloalkynes, alkynyl esters, and alkynyl sulfones. The synthetic merits of TFNf were further underscored with a high-yielding and smooth nucleophilic trifluoromethoxylation of alkyl triflates/bromides and primary/secondary alcohols.
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Affiliation(s)
- Zhichao Lu
- Department of Chemistry, University of Louisville, Louisville, KY, 40292, USA
| | - Tatsuya Kumon
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Gerald B Hammond
- Department of Chemistry, University of Louisville, Louisville, KY, 40292, USA
| | - Teruo Umemoto
- Department of Chemistry, University of Louisville, Louisville, KY, 40292, USA
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17
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Mo F, Qiu D, Zhang L, Wang J. Recent Development of Aryl Diazonium Chemistry for the Derivatization of Aromatic Compounds. Chem Rev 2021; 121:5741-5829. [DOI: 10.1021/acs.chemrev.0c01030] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Fanyang Mo
- Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China
- School of Materials Science and Engineering, Peking University, Beijing 100871, China
| | - Di Qiu
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, College of Chemistry, Tianjin Normal University, Tianjin 300387, China
| | - Lei Zhang
- Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China
| | - Jianbo Wang
- Beijing National Laboratory of Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
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18
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Lu K, Xi X, Zhou T, Lei L, Li Q, Zhao X. Copper-catalysed direct difluoromethylselenolation of aryl boronic acids with Se-(difluoromethyl) 4-methylbenzenesulfonoselenoate. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.152897] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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19
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Wang F, Guo Y, Zhang Y, Tang P. Silver-Catalyzed Dibromotrifluoromethoxylation of Terminal Alkynes. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00090] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | | | | | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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20
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Jiang X, Tang P. Recent Advances of Trifluoromethoxylation Reactions Using
TFMS
and
TFBO. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202000465] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Xiaohuan Jiang
- State Key Laboratory and Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
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21
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Liu S, Huang Y, Xu XH, Qing FL. Fluorosulfonylation of arenediazonium tetrafluoroborates with Na2S2O5 and N-fluorobenzenesulfonimide. J Fluor Chem 2020. [DOI: 10.1016/j.jfluchem.2020.109653] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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22
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Lee JW, Lim S, Maienshein DN, Liu P, Ngai MY. Redox-Neutral TEMPO Catalysis: Direct Radical (Hetero)Aryl C-H Di- and Trifluoromethoxylation. Angew Chem Int Ed Engl 2020; 59:21475-21480. [PMID: 32830430 PMCID: PMC7720849 DOI: 10.1002/anie.202009490] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/12/2020] [Indexed: 12/15/2022]
Abstract
Applications of TEMPO. catalysis for the development of redox-neutral transformations are rare. Reported here is the first TEMPO. -catalyzed, redox-neutral C-H di- and trifluoromethoxylation of (hetero)arenes. The reaction exhibits a broad substrate scope, has high functional-group tolerance, and can be employed for the late-stage functionalization of complex druglike molecules. Kinetic measurements, isolation and resubjection of catalytic intermediates, UV/Vis studies, and DFT calculations support the proposed oxidative TEMPO. /TEMPO+ redox catalytic cycle. Mechanistic studies also suggest that Li2 CO3 plays an important role in preventing catalyst deactivation. These findings will provide new insights into the design and development of novel reactions through redox-neutral TEMPO. catalysis.
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Affiliation(s)
- Johnny W Lee
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery, State University of New York, Stony Brook, NY, 11794, USA
| | - Sanghyun Lim
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery, State University of New York, Stony Brook, NY, 11794, USA
| | - Daniel N Maienshein
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Peng Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Ming-Yu Ngai
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery, State University of New York, Stony Brook, NY, 11794, USA
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23
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Song HX, Tian ZY, Xiao JC, Zhang CP. Tertiary-Amine-Initiated Synthesis of Acyl Fluorides from Carboxylic Acids and CF 3 SO 2 OCF 3. Chemistry 2020; 26:16261-16265. [PMID: 32954583 DOI: 10.1002/chem.202003756] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/16/2020] [Indexed: 01/18/2023]
Abstract
A convenient method for deoxyfluorination of aromatic and aliphatic carboxylic acids with CF3 SO2 OCF3 in the presence of a suitable base at room temperature has been developed. The reaction allows a straightforward access to a variety of acyl fluorides and proves that CF3 SO2 OCF3 is an effective deoxyfluorination reagent for carboxylic acids. The method features simplicity, expeditiousness, high efficiency, ease of handling, good functional group tolerance, a wide range of substrates, excellent yields of products, compatibility of many amine initiators, use of environmentally friendly reagents, and effortless removal of byproducts. This reaction represents the first utilization of trifluoromethyl trifluoromethanesulfonate as a fluorination reagent.
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Affiliation(s)
- Hai-Xia Song
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan, 430070, P. R. China
| | - Ze-Yu Tian
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan, 430070, P. R. China
| | - Ji-Chang Xiao
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Cheng-Pan Zhang
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan, 430070, P. R. China
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24
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Lee JW, Lim S, Maienshein DN, Liu P, Ngai M. Redox‐Neutral TEMPO Catalysis: Direct Radical (Hetero)Aryl C−H Di‐ and Trifluoromethoxylation. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009490] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Johnny W. Lee
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery State University of New York Stony Brook NY 11794 USA
| | - Sanghyun Lim
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery State University of New York Stony Brook NY 11794 USA
| | | | - Peng Liu
- Department of Chemistry University of Pittsburgh Pittsburgh PA 15260 USA
| | - Ming‐Yu Ngai
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery State University of New York Stony Brook NY 11794 USA
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25
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Abstract
A silver-catalyzed trifluoromethoxylation of alkyl trifluoroborates with trifluoromethyl arylsulfonate as the trifluoromethoxylation reagent has been reported for the first time. This reaction is performed under mild reaction conditions and has wide functional group compatibility. In addition, the mechanism of this site-specific trifluoromethoxylation is proposed as a radical pathway.
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Affiliation(s)
- Xiaohuan Jiang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China
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26
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Nyuchev AV, Wan T, Cendón B, Sambiagio C, Struijs JJC, Ho M, Gulías M, Wang Y, Noël T. Photocatalytic trifluoromethoxylation of arenes and heteroarenes in continuous-flow. Beilstein J Org Chem 2020; 16:1305-1312. [PMID: 32595778 PMCID: PMC7308607 DOI: 10.3762/bjoc.16.111] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 05/24/2020] [Indexed: 01/20/2023] Open
Abstract
The first example of photocatalytic trifluoromethoxylation of arenes and heteroarenes under continuous-flow conditions is described. Application of continuous-flow microreactor technology allowed to reduce the residence time up to 16 times in comparison to the batch procedure, while achieving similar or higher yields. In addition, the use of inorganic bases was demonstrated to increase the reaction yield under batch conditions.
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Affiliation(s)
- Alexander V Nyuchev
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands
| | - Ting Wan
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands
| | - Borja Cendón
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands.,Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Carlo Sambiagio
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands
| | - Job J C Struijs
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands
| | - Michelle Ho
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands
| | - Moisés Gulías
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Ying Wang
- Discovery Chemistry and Technologies, AbbVie Inc., 1 North Waukegan, Road, North Chicago, Illinois 60064, United States of America
| | - Timothy Noël
- Micro Flow Chemistry and Synthetic Methodology, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Het Kranenveld, Bldg 14 - Helix, 5600 MB Eindhoven, The Netherlands
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27
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Selective C-H trifluoromethoxylation of (hetero)arenes as limiting reagent. Nat Commun 2020; 11:2569. [PMID: 32444828 PMCID: PMC7244481 DOI: 10.1038/s41467-020-16451-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 05/04/2020] [Indexed: 02/01/2023] Open
Abstract
Methods for direct C-H trifluoromethoxylation of arenes and heteroarenes are rare, despite the importance of trifluoromethoxylated compounds for pharmaceuticals, agrochemicals, and material sciences. Especially selective C-H trifluoromethoxylation of pyridines remains a formidable challenge. Here we show a general late-stage C-H trifluoromethoxylation of arenes and heteroarenes as limiting reagent with trifluoromethoxide anion. The reaction is mediated by silver salts under mild reaction conditions, exhibiting broad substrate scope and wide functional-group compatibility. In addition, ortho-position selective C-H trifluoromethoxylation of pyridines is observed. The method is not only applicable to the gram-scale synthesis of trifluoromethoxylated products but also allows efficient late-stage C-H trifluoromethoxylation of marketed small-molecule drugs, common pharmacophores and natural products. Selective C-H trifluoromethoxylation of pyridines remains a formidable synthetic challenge. Here, the authors report a silver-mediated late-stage C-H trifluoromethoxylation of arenes and heteroarenes as limiting reagents with trifluoromethoxide anion.
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28
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Newton JJ, Jelier BJ, Meanwell M, Martin RE, Britton R, Friesen CM. Quaternary Ammonium Trifluoromethoxide Salts as Stable Sources of Nucleophilic OCF 3. Org Lett 2020; 22:1785-1790. [PMID: 32053386 DOI: 10.1021/acs.orglett.0c00099] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of nucleophilic tertiary amines with trifluoromethyl and pentafluoroethyl methyl ethers provides quaternary ammonium trifluoromethoxide (NR4OCF3) and pentafluoroethoxide (NR4OCF2CF3) salts, respectively, in good yields. The new trifluoromethoxide salts disclosed herein are uniquely stable for extended periods of time in both the solid state and in solution, which complements contemporary reagents. Here we describe the preparation of a range of NR4OCF3 salts, their long-term stability, and utility in substitution reactions.
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Affiliation(s)
- Josiah J Newton
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5A 1S6.,Department of Chemistry, Trinity Western University, Langley, British Columbia Canada, V2Y 1Y1
| | - Benson J Jelier
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5A 1S6
| | - Michael Meanwell
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5A 1S6
| | - Rainer E Martin
- Medicinal Chemistry, Roche Pharma Research and Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, CH-4070 Basel, Switzerland
| | - Robert Britton
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5A 1S6
| | - Chadron M Friesen
- Department of Chemistry, Trinity Western University, Langley, British Columbia Canada, V2Y 1Y1
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29
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Yoritate M, Londregan AT, Lian Y, Hartwig JF. Sequential Xanthalation and O-Trifluoromethylation of Phenols: A Procedure for the Synthesis of Aryl Trifluoromethyl Ethers. J Org Chem 2019; 84:15767-15776. [PMID: 31738556 PMCID: PMC7660230 DOI: 10.1021/acs.joc.9b02717] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecules containing trifluoromethoxyaryl groups are of interest in pharmaceutical, agrochemical, and materials science research, due to their unique physical and electronic properties. Many of the known methods to synthesize aryl trifluoromethyl ethers require harsh reagents and highly controlled reaction conditions and rarely occur when heteroaromatic units are present. The two-step O-trifluoromethylation of phenols via aryl xanthates is one such method that suffers from these drawbacks. Herein, we report a method for the synthesis of aryl trifluoromethyl ethers from phenols by the facile conversion of the phenol to the corresponding aryl and heteroaryl xanthates with newly synthesized imidazolium methylthiocarbonothioyl salts and conversion of these xanthates to the trifluoromethyl ethers under mild reaction conditions.
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Affiliation(s)
- Makoto Yoritate
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | | | - Yajing Lian
- Medicine Design, Pfizer Inc., Groton, Connecticut 06340, United States
| | - John F. Hartwig
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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