Transition-Metal-Free Photoinduced Intramolecular Annulation of 2,3-Di(hetero)arylchromen-4-one

Abstract

An efficient transition-metal-free photoinduced intracyclization of 4H-chromen-4-ones in EtOH-H₂O (7:1, v/v) at ambient temperature for the construction of complicated fused-ring heteroaromatics is established. The reaction proceeds smoothly without requiring any catalysts/additives.