AN EFFICIENT SYNTHESIS OF BENZOPYRANOPYRIMIDINES USING INORGANIC SOLID SUPPORT

Abstract

ABSTRACT 4-Hydroxycoumarin on reaction with aldehydes in the presence of urea/thiourea using solid inorganic support under microwave irradiation (MWI) afforded 4-substituted benzopyrano [4,3-d]- pyrimidine derivatives in a few seconds with improved yield as compared to conventional heating. This efficient, facile and ecofriendly technique avoids the use of excess solvent and toxic acids usually employed in the process.