Metal-free di- and tri-fluoromethylation of alkenes realized by visible-light-induced perylene photoredox catalysis.

Regioselective amino-difluoromethylation of aromatic alkenes C(sp)-CFH and C(sp)-N bond formation with the C[double bond, length as m-dash]C moiety has been achieved in a single operation by visible-light photoredox catalysis. The combination of a shelf-stable and easy-to-handle sulfonium salt, -difluoromethyl--di(-xylyl)sulfonium tetrafluoroborate, and perylene catalysis is the key to the successful transformation. Furthermore, this noble metal-free protocol allows for the photocatalytic trifluoromethylation of alkenes.