An Efficient and Environmentally Friendly Method for Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Catalyzed by Bi(NO3)3 · 5H2O.

Bismuth nitrate pentahydrate catalyzes the three component condensation reaction of an aromatic aldehyde, urea and a β-ketoester or a β-diketone under solvent-free conditions to afford the corresponding dihydropyrimidinones (DHPMs) in high yields. The present method is also effective for the selective condensation of aryl aldehydes in the presence of aliphatic aldehydes. [ABSTRACT FROM AUTHOR]