The Biginelli reaction (Kappe, 1993) is a well-known, simple and straightforward procedure for the synthesis of 3,4-dihydropyrimidinones (3,4-DHPMs) by the three-component condensation of an aliphatic or aromatic aldehyde, b-ketoester and an urea. The original reaction was first reported by Biginelli (1893) and was catalyzed by mineral acids. This simple procedure has been successful in a number of Biginelli reactions involving substrates lacking sterically demanded groups