Silicagel supported sodium bisulfate catalyzes efficiently the three component condensation reaction of aldehyde, beta-ketoester and urea in refluxing acetonitrile to afford the corresponding dihydropyrimidinones. Compared to the classical Biginelli reaction conditions, this new approach consistently has the advantage of excellent yields (84-93%) and short reaction times 1-2.5 h. (C) 2004 Elsevier B.V. All rights reserved.