CALCIUM BROMIDE: AN EFFICIENT CATALYST FOR SYNTHESIS OF DIHYDROPYRIMIDONE DERIVATIVES UNDER MICROWAVE CONDITION

An efficient and ecofriendly method was developed for synthesis of a series ofdihydropyrimidinone derivatives through three-component one-pot cyclocondensationbetween substituted benzaldehydes, beta ketoester and urea/thiourea using calcium bromide asa catalyst under microwave irradiation in a solvent-free condition. The merits of this methodis solvent free approach, low catalyst loading, shorter reaction time, simple workupprocedure, catalyst is easily available, inexpensive and easy to handling. Using this procedure,we synthesized 25 different biologically active dihydropyrimidines