Biginelli three-component condensation of an aldehyde, β-keto ester, and urea proceeds smoothly on the surface of the silver salt of heteropolyacid (HPA), i.e. Ag 3 PW 12 O 40 , in water to afford the corresponding 3,4-dihydropyrimidinones in high-to-quantitative yields under mild conditions. The heterogeneous solid acid provides ease of separation of the catalyst and isolation of the products. The recovered catalyst can be recycled in subsequent reactions with consistent activity.

Synthesis of 3,4-Dihydropyrimidinones. -The use of Ag3PW12O40 allows simple, general, efficient, economic, and environmentally friendly formation of 3,4-dihydropyrimidinones which are of biological interest. The yields are only slightly increased in EtOH. The catalyst can be easily removed and reused in subsequent reactions with consistent activity. -(YADAV*, J. S.; REDDY, B. V. S.; SRIDHAR, P.; REDDY, J. S. S.; NAGAIAH, K.; LINGAIAH, N.; SAIPRASAD, P. S.; Eur.