Visible-Light-Driven\nIron-Catalyzed 1,2-Difluoroalkylthiolation\nof Alkenes

The synthesis of medicinally interesting aryldifluoromethylated\ncompounds has drawn significant research attention in recent years.\nHerein, we report an unprecedented iron-mediated process for the selective\ndefluorination of trifluoromethylarenes to achieve the 1,2-difluoroalkylthiolation\nof alkenes. Preliminary mechanistic studies revealed that thiolate\nanion, trifluoromethylarene, and iron cation could form an electron\ndonor–acceptor (EDA) complex, which induced selective defluorination\nand then difunctionalization of alkenes to obtain aryldifluoromethylated\nproducts. The generated aryldifluoromethylated compounds make it difficult\nto form an EDA complex again, thus avoiding excessive defluorination.\nThis conversion has concise and ambient reaction conditions and provides\nan alternative solution for obtaining difluorobenzylic intermediates.