Synthesis of 4-OXO-4H-Chromene Derivative with Fused Benzodiazepine Ring

Abstract

6-Acetylbenzo[b]chromeno[2,3-e][1,4]diazepin-13(6H)-one 6 was synthesized by reaction of 4- oxo-4H-chromene-3-carboxaldehyde 1 with 1,2-diaminobenzene 2 followed by cyclisation of formed Schiff base 3 and spontaneous oxidation of dihydrodiazepine 4 by air oxygen. Finally, diazepine 5 was acetylated at N(6) by reaction with acetic anhydride.

Keywords

• 4-oxo-4H-chromene
• 1,2-diaminobenzene
• diazepine
• fused heterocycles