Multi-component preparation of diethyl/methyl 1,3-diaryl-1,2,3,6-tetrahydro pyrimidine-4,5-dicarboxylates using hydrated phosphomolybdic acid as an efficient catalyst

The synthesis of diethyl/methyl 1,3-diaryl-1,2,3,6-tetrahydropyrimidine-4,5-dicarboxylates can be achieved using one-pot reaction from dialkylacetylene dicarboxylate, amines, and formaldehyde by employing hydrated phosphomolybdic acid (H3[P(Mo3O10)4].xH2O) as catalyst at room temperature. The effect of various solvent and catalyst amount was investigated. The salient features of the present method are: simple and straightforward work-up, cost-effective and environmentally benign procedure.