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Chinese Chemical Letters 2023年第6期34卷 336-340页

作者： Fang Yuan Hongbao Sun Cheng Yang Haojie Yang Lili Pan Xiaoyang Zhang Rong Tian Lingjun Li Wei Chen Xiaoai Wu Haoxing Wu Huaxi MR Research Center Department of RadiologyFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceFrontiers Science Center for Disease-Related Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China Department of Nuclear Medicine Laboratory of Clinical Nuclear MedicineWest China HospitalSichuan UniversityChengdu 610041China School of Chemistry and Chemical Engineering Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsState Key Laboratory of Cell Differentiation Regulation and Target DrugHenan Normal UniversityXinxiang 453007China

Difluorocarbene has emerged as a valuable intermediate to synthesize fluorides.However,difluorocarbene-derived synthesis of^(19)F/^(18)F-trifluoromethyl triazoles has not been explored.Herein,we reported the Cu(I)-promoted difluorocarbene-derived^(19)F/^(18)F-Trifluoromethylation of iodotriazoles using KF/K^(18)F as the fluorine source.This approach rapidly generated a wide range of 5-trifluoromethyl-1,2,3-triazoles in good yields showing high functional group compatibility.The reaction was effective for late-stage functionalization of bioactive molecules and^(18)F-Trifluoromethylation of iodotriazoles.This work provides a practical synthetic methodology for the development of triazole drugs and^(18)F-radiotracers for positron emission tomography.

关键词： Difluorocarbene Trifluoromethylation Triazole Late-stage functionalization ^(18)F-Labeled radiotracer

Iodomethane as an organocatalyst for the aerobic ortho-selective Trifluoromethylation of pyridines

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Science China Chemistry 2023年第1期66卷 133-138页

作者： Jianjin Yu Renqin Zhan Chao-Jun Li Huiying Zeng State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University.Lanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGll UniversityMontrealOuebec H3A OB8Canada

Iodomethane is usually used as an electrophilic methylation reagent.Herein,we report its use as a C1 organocatalyst for the aerobic ortho-selective Trifluoromethylation of pyridines in the absence of a transition metal.Trifluoroacetic acid(TFA)was employed as an inexpensive,readily available trifluoromethyl source.The reaction efficiently produced a variety of Trifluoromethylation products,with good functional group compatibility.Pyridine-containing drug molecules could also be selectively trifluoromethylated for late-stage functionalizations.Mechanistic studies showed that iodomethane selectively reacted with the pyridine starting material,rather than the pyridine product,to generate the corresponding N-methylpyridinium iodide.The decarboxylation of trifluoroacetic acid produced a trifluoromethyl anion,which added to the methylpyridinium iodide,and the subsequent aerobic rearomatization led to the generation of the ortho-trifluoromethylated product.

关键词： iodomethane-catalysis Trifluoromethylation pyridines transition-metal-free trifluoroacetic acid

Catalyst-free,direct electrochemical Trifluoromethylation/cyclization of N-arylacrylamides using TfNHNHBoc as a CF_(3) source

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Chinese Chemical Letters 2022年第1期33卷 221-224页

作者： Han Wang Yongbin Xie Yicheng Zhou Nannan Cen Wenbo Chen Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China CAS Key Laboratory of Energy Regulation Materials Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A new electrochemical strategy for Trifluoromethylation/cyclization using TfNHNHBoc as a CF_(3)source was established.This approach was realized by the direct electrolysis of Tf NHNHBoc under external oxidantfree and catalyst-free conditions,and afforded various trifluoromethylated oxindoles with good functional group compatibility and broad substrate scope.Preliminary mechanistic studies show that the reaction proceeds by a radical process.

关键词： Electrolysis Trifluoromethylation Cyclization TfNHNHBoc Radical process

Advances in the Transition Metal-Free C—H Trifluoromethylation

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Chinese Journal of Chemistry 2022年第21期40卷 2582-2594页

作者： Demao Chen Jianwen Jiang Jie-Ping Wan Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchangJiangxi 330022China.

Trifluoromethyl group is one of the most frequently available and promising functional groups in pharmaceutical,agrochemical as well as material molecules.Developing synthetic methods for the synthesis of trifluoromethyl functionalized compounds by Trifluoromethylation reactions occupies significant position in modern organic chemistry.On the other hand,as a typical tool of sustainable synthesis,transition metal-free synthesis possesses unique advantages in atom economy,easy product purification as well as excellent eco-tolerance.Consequently,transition metal-free Trifluoromethylation reactions constitute the most important approaches for accessing trifluoromethylated molecules.Herein,the advances in the transition metal-free C—H Trifluoromethylation reactions are reviewed for the first time.According to the updated state-of-art,both the catalytic reactions by conventional heating chemistry and the more sustainable photocatalysis are included,covering the Trifluoromethylation reactions of C(sp^(3))–H bond,aromatic C(sp^(2))–H bond as well as the non-aromatic C(sp^(2))–H bond in different substrates over the last five years(2017—2021).

关键词： C-H bond Trifluoromethylation Transition metal-free Thermochemistry Photocatalysis

External-Oxidant-Free Electrochemical Oxidative Trifluoromethylation of Arenes Using CF3SO2Na as the CF3 Source

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Chinese Journal of Chemistry 2019年第8期37卷 817-820页

作者： Yong Deng Fangling Lu Siqi You Tianrui Xia Yifan Zheng Cuifen Lu Guichun Yang Zuxing Chen Meng Gao Aiwen Lei Ministry-of-Educotion Key Laboratory for the Synthesis and Application of Organic Functional Molecule & School of Chemistry and Chemical Engineering Hubei UniversityWuhanHubei 430072China National Research Center for Carbohydrate Synthesis Jiangxi Normal UniversityNanchangJiangxi 330022China College of Chemistry and Molecular Sciences the Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China

Summary of main observation and conclusion An efficient and environmentally benign electrochemical oxidative radical C-H Trifluoromethylation of arenes by employing Langlois reagent as the CF3 source was developed in this work.Neither transition metal catalysts nor external chemical oxidants were required in this Trifluoromethylation process.The reaction could be conducted in gram scale with high reaction efficiency.

关键词： External-Oxidant-Free Electrochemical Oxidative Trifluoromethylation CF3SO2Na CF3

Copper-catalyzed α-selective C–H Trifluoromethylation of acrylamides with TMSCF3

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Chinese Chemical Letters 2019年第5期30卷 969-972页

作者： Shang-Zheng Sun Hui Xu Hui-Xiong Dai Department of Medicinal Chemistry Shanghai Institute of Materia MedicaUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 201203China Department of Chemistry Innovative Drug Research CenterShanghai UniversityShanghai 200444China

A copper-catalyzedα-selective C–H Trifluoromethylation of acrylamides with TMSCF3 is described.A wide range of arenes and heteroarenes at theβ-position of acrylamides are compatible with the reaction,affording the corresponding(E)-trifluoromethylated products in moderate to good yields.The reaction proceeded fast and can be completed within 30 min.

关键词： a-Selectivity C-H Trifluoromethylation Copper Acrylamides Heterocycle

DBU-Promoted Trifluoromethylation of Aryl Iodides with Difluoromethyltriphenylphosphonium Bromide

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Chinese Journal of Chemistry 2016年第5期34卷 481-484页

作者： Yun Wei Liuying Yu Jinhong Lin Xing Zheng Jichang Xiao Institute of Pharmacy and Pharmacology University of South China 28 Western Changsheng Road Hengyang Hunan 421001 China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study Institute of Pharmacy and Pharmacology University of South China 28 Western Changsheng Road Hengyang Hunan 421001 China

DBU-promoted Trifluoromethylation of aryl iodides with difluoromethyltriphenylphosphonium bromide （DFPB） in the presence of copper source is described. In this transformation, DBU not only acts as base to deprotonate the difluoromethyl group in DFPB to generate difluoromethylene phosphonium ylide Ph3P＋CF2 , but also converts the difluorocarbene generated from ylide Ph3P＋CF2- into trifiuoromethyl anion, finally resulting in the trifluoromethy- lation of aryl iodides. The reactions proceeded smoothly to afford expected products in moderate to good yields.

关键词： difluorocarbene Trifluoromethylation difluoromethyltriphenylphosphonium bromide copper

Copper-Catalysed Decarboxylative Trifluoromethylation of β-Ketoacids

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Chinese Journal of Chemistry 2017年第11期35卷 1665-1668页

作者： Xiaolan Xu Huanhuan Chen Jianbo He Huajian Xu School of Chemistry and Chemical Engineering Hefei University of Technology Hefei Anhui 230009 China School of Medical Science Anhui Medical University Hefei Anhui 230009 China

An efficient method for Cu-catalyzed decarboxylative Trifluoromethylation offl-ketoacids to achieve a-trifluoro- methyl ketones was developed. A wide variety of synthetically useful α-trifluoromethyl ketones were obtained in modest to good yields under mild reaction conditions. The present method also exhibits good functional-group compatibility.

关键词： β-ketoacids decarboxylative Trifluoromethylation α-trifluoromethyl ketones

Activation of Trifluoromethylthio Moiety by Appending Iodonium Ylide under Copper Catalysis for Electrophilic Trifluoromethylation Reaction

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Chinese Journal of Chemistry 2016年第5期34卷 485-489页

作者： Ibrayim Saidalimu Shugo Suzuki Etsuko Tokunaga Norio Shibata Department of Frontier Materials Nagoya Institute of Technology Gokiso Showa-ku Nagoya 466-8555 Japan Department of Nanopharmaceutical Sciences Nagoya Institute oF Technology Gokiso Showa-ku Nagoya 466-8555 Japan

A novel iodonium-ylide compound 2 that appends a trifluoromethylthio （SCF3） group is disclosed as a new, shelf-stable electrophilic Trifluoromethylation reagent. Unlike known shelf-stable electrophilic Trifluoromethylation reagents, 2 has a stable SCF3 group which is activated by appending iodonium ylide under copper catalysis via sul- fonium ylide to generate a cationic trifluoromethyl （CF3） species. Reagent 2 was found to be an efficient electro- philic Trifluoromethylation reagent for a wide range of silyl enol ethers 3 under copper catalysis. Cyclic and acyclic a-trifiuoromethyl ketones 4 were obtained by reagent 2 in moderate to good yields. On the other hand, a difluoro- methylthio analogue 5 did not affect intermolecular transfer difluoromethylation to substrates. Instead, intramolecu- lar 1,4-migration proceeded similar to the Stevens rearrangement to provide 6 in 21% yield, independent of the presence of nucleophiles 3.

关键词： Trifluoromethylation difluoromethylation iodine sulfur ylide

Trifluoromethyl Radical Addition versus Radical Trifluoromethylation:Reversed Regioselectivity in CarboTrifluoromethylation of Alkenes

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Chinese Journal of Chemistry 2019年第6期37卷 630-631页

作者： Zhenzhen Zhang Lin Zhu Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Professor Chaozhong Li's research group has long been interested in radicals in organic synthesis. They have developed a series of silver-catalyzed radical fluorination reactions since the year 2012.[1] In 2015, the research group joined the Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences. I joined the Li group in the same year.

关键词： alkenes radical reactions Trifluoromethylation regioselectivity