Radical C−H Bond Trifluoromethylation of Alkenes by High‐Valent Copper(III) Trifluoromethyl Compounds

A general and selective method is developed that allows direct vinylic C−H bond trifluoromethylation of 1,1‐diarylalkenes by a high‐valent copper(III) trifluoromethyl complex, producing biologically active trifluoromethylated alkenes (as well as trifluoromethylated carbocyclic compounds). This fundamental reactivity of Cu(III)−CF3 compounds has thus far been unknown. The presence of a tertiary amine is crucial to this reaction, acting as both a weak base and a single electron transfer (SET) promoter to the vinylic hydrogen. This method starts from bulk olefins under cost‐effective conditions (without the need for external noble metal photocatalyst or stoichiometric amounts of oxidant), and thus is valuable for practical and sustainable applications.