Selective Fluoromethyl Couplings of Alkynes via Nickel Catalysis
Huan Li1, Fang Wang1, Shengqing Zhu1
1State Key Laboratory for Modification of Chemical Fibers Sand Polymer Materials, Center for Advanced Low-Dimension Materials, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China.
Abstract:
We describe here a Ni-catalyzed intermolecular carbo-fluoromethylation of alkynes with aliphatic halides and fluoromethyl halides (BrCF2 H and ICH2 F) in the presence of zinc, enabling the facile and selective access to a diverse range of biologically valuable CF2 H/CH2 F-incorporated alkenes with excellent regio- and stereoselectivity. Notably, merging intramolecular radical cyclization with fluoromethyl coupling enables the expedient constructions of CF2 H/CH2 F-incorporated lactones and lactams with high efficiency and selectivity. Mechanistic studies disclose that this catalytic protocol proceeds via a radical addition to an alkyne followed by selective coupling with the fluoromethyl unit.
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