Photocatalytic Trifluoromethylthiolation of Aromatic Alkenes Associated with Hydroxylation and Alkoxylation

A photoredox‐catalyzed trifluoromethylthiolation process of aromatic alkenes has been developed. A strongly reducing photocatalyst, fac ‐[Ir(4‐MeO‐ppy) 3 ] (4‐MeO‐ppy=2‐pyridyl‐5‐methoxyphenyl), and an electrophilic trifluoromethylthiolating reagent, 1‐(trifluoromethylthio)pyrrolidine‐2,5‐dione ( 1 a ), play key roles in the efficient generation of a trifluoromethansulfenyl radical ( . SCF 3 ). The well‐designed photoredox system induces a single‐step, regioselective installation of a CF 3 S and a hydroxy or an alkoxy group onto vicinal carbon atoms through redox‐neutral processes. The present oxytrifluoromethylthiolation features mild reaction conditions without extra additives for the activation of the CF 3 S reagent, making the present protocol applicable to a wide variety of functionalized aromatic alkenes.