Cocrystallisation of succinic and fumaric acids with lutidines: a systematic study

Abstract

A series of cocrystals and salts of succinic and fumaric acids and the isomers of lutidine have been prepared. The crystal structures of six lutidine–succinic acid cocrystals, four lutidine fumarate salts, and two lutidine–fumaric acid cocrystals have been determined. The crystal structures are compared and discussed in the light of similar features, particularly the formation of three-molecule base–acid–base units, which appears to be important for the stability of the crystal. The packing of these units is found to be very sensitive to methyl group position.