A facile one step synthesis of 3-(2-oxo-2H-chromen-3-yl)-indeno- [2,1-c]pyridazin-9-one

Abstract

3-Acetylcoumarins (1) on reaction with ninhydrin (2) in acetic acid followed by treatment of in situ formed 2-hydroxy-2-[2-oxo-2-(2-oxo-2H-chromen-3-yl)-ethyl]indan-1,3-diones (3) with hydrazine hydrate resulted in the formation of corresponding 3-(2-oxo-2H-chromen-3-yl)-indeno[2,1-c]pyridazin-9-ones (4) in a single step with an excellent yields. The structures of newly synthesised compounds (4) were confirmed by unambiguous synthesis involving a two step process from 3-acetylcoumarins.