Cheng Ran, Sang Yueqian, Gao Xing, Zhang Shu, Xue Xiao-Song, Zhang Xingang
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 Lingling Lu, Shanghai, 200032, China.
College of Chemistry, Nankai University, Tianjin, 300071, P. R. China.
Angew Chem Int Ed Engl. 2021 May 25;60(22):12386-12391. doi: 10.1002/anie.202015921. Epub 2021 Apr 20.
A nickel-catalyzed highly γ-regioselective arylation and carbonylative arylation of 3-bromo-3,3-difluoropropene has been developed. The reaction proceeds under mild reaction conditions, providing the gem-difluoroalkenes with high efficiency and good functional group tolerance. The resulting gem-difluoroalkenes can serve as versatile building blocks for diversified synthesis. Preliminary mechanistic studies and density functional theory calculations reveal that both non-radical and radical pathways are possible for the reaction, and the radical pathway is more likely. The high γ-regioselectivity results from the β-bromide elimination of alkylnickel(II) species or from the reductive elimination of nickel(III) species [(aryl)(CF =CHCH )Ni (L )X]. The γ-selective carbonylation of 3-bromo-3,3-difluoropropene under 1 atm CO gas also provides a new way for nickel-catalyzed carbonylation.
已开发出一种镍催化的3-溴-3,3-二氟丙烯的高度γ-区域选择性芳基化和羰基化芳基化反应。该反应在温和的反应条件下进行，能高效地提供偕二氟烯烃，且具有良好的官能团耐受性。所得的偕二氟烯烃可作为多样化合成的通用结构单元。初步的机理研究和密度泛函理论计算表明，该反应的非自由基和自由基途径均有可能，且自由基途径更有可能。高γ-区域选择性源于烷基镍（II）物种的β-溴消除或镍（III）物种[(芳基)(CF =CHCH )Ni (L )X]的还原消除。在1 atm CO气体下3-溴-3,3-二氟丙烯的γ-选择性羰基化反应也为镍催化的羰基化反应提供了一种新方法。
