Iron‐Catalyzed Direct C3‐H Trifluoromethylthiolation of Quinoxalin‐2(1H)‐ones

An iron‐catalyzed direct C3‐H radical trifluoromethylthiolation of quinoxalin‐2(1H)‐ones has been developed. This protocol use earth‐abundant FeSO4·7H2O as the catalyst, and AgSCF3 as the trifluoromethylthiolating reagent to provide various SCF3‐containing quinoxalin‐2(1H)‐one derivatives in 26‐88% yields. Preliminary mechanistic investigations indicate that the reaction proceeds through a radical pathway.