Europium-Catalyzed Intramolecular Oxazole Diels-Alder Reactions for the Synthesis of Benzopyrano(4,3-b)pyridines and Benzo(h)-1,6-naphthyridines.

Intramolecular oxazole-olefin Diels-Alder reactions proceed, in the presence of the Lewis acid europium(fod)3, to provide substituted 5H-[1]-benzopyrano[4,3-b]pyridines and benzo[h]-1,6 naphthyridines in moderate yields.