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Chinese Journal of Chemistry 2018年第3期36卷 206-212页

作者： Bo Xing Chuanfa Ni 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 345Lingling Lu Shanghai 200032 China

A copper-mediated di- and monoffuoromethanesulfonylation of arenediazonium tetrafluoroborates using di- and monofluoromethanesul- finate reagents provides aryl difluoromethyl （or monofluoromethyl） sulfones in 8ood yields. It was found that the relative reactivity of these sodium fluoroalkanesulfinates in the present reactions decreases in the followin8 order： CH2FSO2Na 〉 CF2HSO2Na 〉 CF3SO2Na.

关键词： difluoromethanesulfonylation fluoromethanesulfonylation arenediazonlum sodium sulfinate fluorine effect

Enantioselectivity Tunable Gold-Catalyzed Intermolecular[3+2]Cycloaddition of N-Allenamides with Nitrones

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Chinese Journal of Chemistry 2022年第12期40卷 1407-1412,I0002页

作者： Bing Xu Zhan-Ming Zhang Jie Han Guangxin Gu Junliang Zhang Department of Chemistry Fudan University2005 Songhu RoadShanghai 200438China Department of Materials Science Fudan University2005 Songhu RoadShanghai 200438China Zhuhai Fudan Innovation Institute ZhuhaiGuangdong 519000China

A highly enantioselective gold-catalyzed intermolecular[3+2]cycloaddition of N-allenamides with nitrones was realized by the application of Ming-Phos M6 as a chiral ligand.Both enantiomers of the cycloadducts with opposite configuration could be obtained in high yields with high regio-and enantioselectivity by the employment of either diastereomer of the chiral ligand.The acidic N—H bond(hydrogen bonding)of sulfinamide moiety of Ming-Phos and pentaflurophenyl substituent(fluorine effect)may play important roles in enhancement of enantioselectivity,that is,Ming-Phos is a multifunctional ligand in this transformation.

关键词： Gold Asymmetric catalysis fluorine effect Cycloaddition Multifunctional ligand

Diastereoselective Construction of α-Fluoroalkyl Cycloalkanols via Radical Alkylation of α-Fluoroalkyl Ketones

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Chinese Journal of Chemistry 2023年第23期41卷 3275-3280页

作者： Yi Liu Ji Li Yulu Zhou Hanliang Zheng Zhenlu Shen Gangguo Zhu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of ChemistryZhejiang Normal University688 Yingbin RoadJinhuaZhejiang321004 China College of Chemical Engineering Zhejiang University of TechnologyHangzhouZhejiang310032 China

α-Fluoroalkyl (Rf) alcohols are privileged motifs in drugs and pharmaceutically active compounds.As such,it is highly desirable to develop efficient methods for assembling these scaffolds.Herein,a visible-light-induced cascade radical cyclization of alkenyl fluoroalkyl ketones is developed,producing a variety of decorate α-Rf cycloalkanols in promising yields with up to >20 : 1 dr selectivity.A radical chain mechanism involving an intramolecular radical addition to the α-Rf carbonyl group and a subsequent intermolecular hydrogen atom transfer (HAT) has been proposed.Density functional theory (DFT) calculations indicate that a fluorine effect contributes to the radical addition to carbonyls by lowering the π* (C=O) orbital energy of CORf and energy barrier of the HAT between alkoxy radicals and THF,which may be valuable for controllable transformations of fluorinated molecules.

关键词： Radical reactions Cyclization Alkylation α-Fluoroalkyl ketones fluorine effect Alcohols

fluorine effects for Tunable C-C and C-S Bond Cleavage in Fluoro-Julia-Kocienski Intermediates

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CCS Chemistry 2021年第6期3卷 1678-1689页

作者： Lei Kang Yongjia Lin Zeng Gao Jinlong Zhang Huameng Yang Jinlong Qian Qian Peng Gaoxi Jiang State Key Laboratory for Oxo Synthesis and Selective Oxidation Center for Excellence in Molecular SynthesisSuzhou Research Institute of LICPLanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhou 730000 State Key Laboratory of Element-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071 University of Chinese Academy of Sciences Beijing 100049

Classical Julia-Kocienski fluoroolefination represents an indispensable platform for the construction of monofluoroalkenes.Nevertheless,its complex multistep mechanistic manifold along with the unrevealed intrinsic“fluorine effect”in nucleophilic reactions might be responsible for the difficult control of the original stereoselectivity and is thus often ambiguous to predict.Herein,a novel strategy involving the defined fluorine effect and new reaction mechanism was developed for tunable C-C and C-S bond cleavage,providing a versatile avenue for highly stereoselective and easily scalable construction of diverse monofluoroalkenes.Density functional theory(DFT)investigations indicate the fluorine substituents can activate the C-C and C-S bond leading toα-elimination by antiphase orbital interaction.The rate-limiting step were calculated via fourmembered transition states with ring strain.Both the sterically eclipsed repulsion and secondary orbital interaction affect the stereoselectivity.

关键词： fluorine effect monofluoroalkene Julia-Kocienski fluoroolefination DFT calculation frontier molecular orbital