Nickel-Catalyzed Markovnikov-Selective Hydrodifluoromethylation of Alkynes Using BrCF
Shiwei Pan1, Fan Chen1, Yanyan Zhang1
1State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Center for Advanced Low-dimension Materials, Donghua University, Shanghai, 201620, China.
Abstract:
A Markovnikov-selective hydrodifluoromethylation of alkynes with BrCF2 H via nickel catalysis is described. This protocol proceeds via a migratory insertion of nickel hydride to alkyne followed by a CF2 H-coupling, enabling straightforward access to diverse branched CF2 H-alkenes with high efficiency and exclusive regioselectivity. The mild condition applies to a wide array of aliphatic and aryl alkynes with good functional group compatibility. Mechanistic studies are presented to support the proposed pathway.
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