H2SO4-Silica Catalyzed One-Pot and Efficient Synthesis of Dihydropyrimidinones Under Solvent-Free Conditions

Abstract

H2SO4-Silica efficiently catalyzes the three-component condensation reaction of aldehydes, 1,3-dicarbonyl compounds and urea/thiourea under solvent free conditions to afford the corresponding dihydropyrimidinones and thio-derivatives in high yields. Compared to the classical Biginelli reaction conditions, this new method consistently has the advantage of giving good yields and requiring short reaction times.