Ion exchange resins as recyclable and heterogeneous solid acid catalysts for the Biginelli condensation:An improved protocol for the synthesis of 3,4-dihydropyrimidin-2-ones

A simple and efficient protocol has been developed for the synthesis of 3,4-dihydropyrimidin-2-ones using ion exchange resins as recyclable, heterogeneous, environmentally benign catalysts under mild reaction conditions. Among the various solid acid catalysts Nafion NR-50 was found to be most efficient catalyst. Keywords: Biginelli condensation; 3,4-Dihydropyrimidin-2-ones; Ion-exchange resin; Heterogeneous catalysi