Visible-Light-Induced Phosphorylation of Imidazo-Fused Heterocycles under Metal-Free Conditions.

A metal-free and base-free procedure for the phosphorylation of imidazo[1,2-a]pyridines with phosphine oxides under the irradiation of visible light at room temperature in green solvent was reported, featuring mild and sustainable conditions, convenient operation, as well as good functional group compatibility.