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.