NOVEL [DBN][HSO4] MEDIATED FACILE AND EFFICIENT SYNTHESIS OF DIHYDROPYRIMIDO [4, 5-D]PYRIMIDINE DERIVATIVES

Abstract

A [DBN][HSO4] bronsted acidic ionic liquid promoted condensation followed by cyclization protocol has been developed for the first time by a successive reaction of aldehydes, barbituric acid and urea to afford dihydropyrimido [4,5-d] pyrimidine derivatives in high to excellent yields under microwave irradiation (MW=240W). The ionic liquid provided the capability to allow a variability of functional groups, easy workup, short reaction times, and recyclability of the catalyst, high yields and solvent-free conditions, thus providing economic and environmental advantages.