Transition‐Metal‐Free Three‐Component Chalcogen‐Trifluoromethylation of Alkenes Enabled by a Catalytic Electron Donor‐Acceptor Complex†

Comprehensive Summary The transition metal‐free chalcogen trifluoromethylation of alkenes represents a highly efficient transformation for the rapid generation of C(sp 3 )‐rich aliphatic trifluoromethyl compounds. However, a unified methodology to achieve oxy‐, thio‐, and seleno‐trifluoromethylation remains elusive yet highly desirable. In this study, we report a triarylamine‐catalyzed three‐component vicinal chalcogen‐trifluoromethylation of alkenes under blue light irradiation without the need of transition metal catalyst. This reaction is broadly applicable to oxy, thio, and seleno nucleophiles, facilitating modular access to a diverse array of β‐trifluoromethyl alcohols, ethers, thioethers, thiocyanates, and selenocyanates with good yields and predictable regioselectivities (61 examples). Additionally, we demonstrate its application in the late‐stage modification of natural products and pharmaceutical compounds. Preliminary mechanistic studies suggest that a catalytic electron donor‐acceptor (EDA) complex between triarylamine and the Umemoto reagent is key to enabling the radical/polar crossover process.