Ethyl 6-methyl-4-[2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)thiophen-3-yl]-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate

Abstract

A new Biginelli compound, C18H25BN2O4S2, containing a boronate ester group was synthesized from a lithium bromide-catalysed reaction. The compound crystallizes with two independent molecules in the asymmetric unit that differ mainly in the conformation of the ester functionality. The crystal structure is stabilized by intermolecular N—H...O and N—H...S hydrogen bonds involving the 3,4-dihydropyrimidine-2(1H)-thione NH groups as donors and the carbonyl O and thiophene S atoms as acceptors.