Synthesis of 2-Methyl-3-acetyl-5-oxo-5H-[1]benzopyrano[2,3-b]pyridine

Abstract

For our synthetic work we needed the title compound. Literature survey revealed that 2-amino-4-oxo-4H-[1] benzopyran-3-carboxaldehyde (2-amino-3-formylchro-mone) can undergo condensation with diethyl malonate (or ethyl cyanoacetate) forming ethyl 2-hydroxy(or amino)-5-oxo-5H-[1]benzopyrano[2,3-b]pyridine-3-carboxylate¹.