Nickel-Catalyzed anti-Markovnikov Hydrodifluoroalkylation of Unactivated Alkenes
Li-Ming Yin1, Meng-Chan Sun1, Xiao-Ju Si1
1Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, PR China.
Abstract:
An efficient Ni-catalyzed hydrodifluoroalkylation of unactivated alkenes with bromodifluoroacetate by using PhSiH3 as hydride source was developed. The transformation affords aliphatic difluorides with anti-Markovnikov regioselectivity. A wide range of highly remote alkenes, simple alkenes, drug molecules, commercially available CF2 precursors, and even nonfluorinated substrates are competent in this reaction under mild conditions, demonstrating the practicability of the strategy. Moreover, mechanistic studies indicated that the difluoroalkyl radical might be a key intermediate to this transformation.
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