Organic Photoredox-Catalyzed S -Trifluoromethylation of Aromatic and Heteroaromatic Thiols.

A visible-light-mediated trifluoromethylation protocol was developed for the conversion of (hetero)aromatic thiols to their respective S -trifluoromethylated derivatives employing trifluoromethanesulfonyl chloride (CF 3 SO 2 Cl) as a cost-effective source of trifluoromethyl radical (CF 3 ·) and a highly reducing organophotocatalyst, 3DPA2FBN. The developed methodology is operationally simple, providing access to a diverse range of products in up to 92% yield. A plausible mechanism has been postulated based on preliminary mechanistic studies, including irradiation on/off, UV-vis studies, and radical trapping experiments.