EtAlCl2-promoted defluorinative thiolation of α-trifluoromethyl alkenes

Abstract

Here, we report a EtAlCl₂-promoted thiolation of trifluoromethyl alkenes, which leads to the complete substitution of all three fluorine atoms and affords trisubstituted products. Although the transformation proceeds through a three-step sequence, it maintains high efficiency and delivers the target product in good to excellent yields. Mechanistic studies indicate that the reaction initially forms a gem-difluoroalkene intermediate. The newly introduced thioether group then activates the remaining C–F bonds, thereby facilitating subsequent substitution to afford the trisubstituted products.