Visible light-induced synthesis of benzofuro[3,2-b]pyridines from aurone-derived azadienes

Abstract

The visible light-induced regioselective synthesis of benzofuro[3,2-b]pyridines from aurone-derived azadienes is achieved through a radical dimerization/aromatization mechanism under catalyst-free conditions. In specific instances, spiro[benzofuran-2,2′-benzofuro[3,2-b]pyridines] are formed as intermediates, which can then be converted into the target benzofuro[3,2-b]pyridines by treatment with a base under heating conditions.