Diisopropyl azodicarboxylate mediated selective dehydrogenation of 2-amino-3-cyano 4H-chromenes

Abstract Selective dehydrogenation of 2-amino-3-cyano 4 H -chromenes to the corresponding 2-iminochromenes mediated by diisopropyl azodicarboxylate under neutral conditions is reported. The dehydrogenation reaction is compatible with phenolic hydroxyl group and generates iminochromene in high yields. The methodology provides an easy access to coumarin and N -tosyl 2-amino-3-cyano-4-aryl 4 H -chromenes.