Zinc–Brønsted acid mediated practical hydrotrifluoromethylation of alkenes with CF3Br

Abstract

We report a mild and efficient hydrotrifluoromethylation of alkenes with bromotrifluoromethane (CF₃Br) mediated by zinc and a Brønsted acid. This reaction proceeds well with good functional group compatibility and broad substrate scope. Mechanistic studies indicate that the reaction proceeds through a radical pathway, facilitated through the combination of the zinc metal and a Brønsted acid for the single electron reduction of CF₃Br to the CF₃ radical. Furthermore, the method readily allows the incorporation of deuterium using deuterated carboxylic acid and D₂O.