Metal-Free Thiocyanation of Imidazoheterocycles through Visible Light Photoredox Catalysis

A visible
light mediated, metal-free process for the thiocyanation
of imidazoheterocycles has been developed using eosin Y as a photoredox
catalyst under ambient air at room temperature. A library of 3-(thiocyanato)­imidazo­[1,2-a]­pyridines with broad functionalities have been synthesized
in high yields. This methodology is also applicable for the selenocyanation
of imidazo­[1,2-a]­pyridine.