Lanthanum–Catalyzed One–Pot Synthesis of Chromeno–Fused Pyridine/Quinolinone Derivatives

Abstract

AbstractA novel one‐pot approach has been developed for the preparation of 5‐oxo‐5H‐chromeno[4,3‐b] pyridine‐3‐carboxylates and 6H‐chromeno[4,3‐b] quinolin‐6‐ones by reacting 2‐((benzylimino/phenylimino)‐methyl) phenols with ethyl/methyl propiolate in presence of La(OTf)3 under thermal conditions. The reactions proceeded through the formation C−O, C−N and C−C bonds to form the title compounds. The bio–active compound 6H‐chromeno[4,3‐b] quinolin‐6‐one has been prepared by this protocol.