A visible-light-induced bromine radical initiates direct C-H alkylation of heteroaromatics.

Herein, a photoinduced direct C(sp 2 )-H alkylation of N -heteroaromatics by using commercially available tetrabutylammonium tribromide (TBATB) as a HAT reagent is described. The method uses O 2 as the oxidant, and features metal-free, mild reaction conditions and good functional group compatibility.