A four-component radical cascade trifluoromethylation reaction of alkenes enabled by an electron-donor–acceptor complex

An efficient four-component radical cascade reaction of alkenes, enabled by an EDA complex between Togni's reagent and Hantzsch ester, has been reported. This operationally simple protocol demonstrates excellent selectivity, which is dominated by the innate polar effect, providing facile access to important δ-CF3 carbonyls under mild conditions. To further demonstrate the wide synthetic utility of this method, a three-step synthesis of CF3-naftidrofuryl has been successfully conducted.