Copper-catalyzed trifluoromethylation of styrene derivatives with CF₃SO₂Na

An efficient copper(i)-catalyzed trifluoromethylation of styrene derivatives using CF₃SO₂Na as a trifluoromethylating source in the presence of ^tBuOO^tBu has been developed. Mechanistic studies show that the reaction likely proceeds via a radical pathway, providing a general and straightforward access to trifluoromethylated styrene derivatives. Advantageously, excellent stereoselectivity is obtained with styrene derivatives in this transformation.