Phosphine-Mediated Photocatalytic Defluorinative Reductive Coupling of Alkynes and Trifluoromethyl Alkenes
Linqing Ding1, Yihong Li1, Dong-Fang Jiang2
1Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan411105, China.
Abstract:
The reductive coupling of alkynes and alkenes has emerged as a straightforward protocol for C-C bond formation from readily available feedstocks. Herein, we report a phosphine-mediated photocatalytic defluorinative reductive coupling of alkynes and trifluoromethyl alkenes with water as the hydrogen source, delivering a range of valuable gem-difluoroalkenes with excellent chemoselectivity under mild conditions. This strategy is gram-scale and can be applied for several pharmaceutical and natural product derivatives. Control experiments and spectroscopic analyses were conducted to probe the underpinning mechanism.
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