Visible-light-induced dehydrogenative β-trifluoromethylthiolation of tertiary amines and direct β-trifluoromethylthiolation of enamides†

Facilitated by electron donor–acceptor complexes, an efficient dehydrogenative β-trifluoromethylthiolation of tertiary amines with N-trifluoromethylthiophthalimide is presented under transition-metal-free, external oxidant-free, photocatalyst-free and mild reaction conditions. This protocol accommodates a range of substituted piperidines, as well as seven- and eight-membered saturated heterocycles. Additionally, employing this photocatalyst-free approach, direct β-trifluoromethylthiolation of electron-rich enamides was also achieved through the involvement of a photoactive electron donor–acceptor (EDA) complex.