Metal-free C-3 selective C(sp 2 )-C(sp 3 ) heteroarylation of anilines with imidazo[1,2- a ]pyridine derivatives via cross-dehydrogenative coupling.

A general and straightforward method for the regioselective construction of C-3 heteroaryl-containing imidazo[1,2- a ]pyridines via cross-dehydrogenative coupling under transition-metal-free conditions has been reported, utilizing N , N -dimethylaniline as the methylenation source and furnishing the C(sp 2 )-C(sp 3 ) functionalized products in good to excellent yields. Mechanism studies indicate that a radical pathway is responsible for this transformation.