Ma Qiao, Wang Yanhui, Tsui Gavin Chit
Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, Hong Kong.
Angew Chem Int Ed Engl. 2020 Jul 6;59(28):11293-11297. doi: 10.1002/anie.202002219. Epub 2020 May 8.
A stereoselective Pd(PPh ) -catalyzed C-F bond alkynylation of tetrasubstituted gem-difluoroalkenes with terminal alkynes has been developed. This method gives access to a great variety of conjugated monofluoroenynes bearing a tetrasubstituted alkene moiety with well-defined stereochemistry. Chelation-assisted oxidative addition of Pd to the C-F bond is proposed to account for the high level of stereocontrol. An X-ray crystal structure of a key monofluorovinyl Pd intermediate has been obtained for the first time as evidence for the proposed mechanism.
已开发出一种立体选择性的钯（PPh ）催化的四取代偕二氟烯烃与末端炔烃的C-F键炔基化反应。该方法能够合成多种具有明确立体化学的带有四取代烯烃部分的共轭单氟烯炔。据推测，钯对C-F键的螯合辅助氧化加成是实现高立体控制水平的原因。首次获得了关键的单氟乙烯基钯中间体的X射线晶体结构，作为所提出机理的证据。
