Vanillic aldehydes for the one-pot synthesis of novel 2-oxo-1,2,3,4-tetrahydropyrimidines

A small library of novel 2-oxo-1,2,3,4-tetrahydropyrimidines was synthesized via a one-pot multicomponent Biginelli reaction. Copper complex which was used for the first time as a homogeneous and heterogeneous catalyst, makes this a facile and efficient reaction at room temperature. All the obtained products fall out of the solution in pure form and are easily isolated via filtration in good-to-excellent yields. The molecular structure of one of the products, ethyl 6-methyl-2-oxo-4-(4-isopropoxy-3-methoxyphenyl) - 1,2,3,4 - tetrahydropyrimidine-5- carboxylate, has been determined by X-ray crystallography. All non-hydrogen atoms in the heterocyclic, six-membered ring are determined to be approximately coplanar.