Cocrystals of 2,4-Diamino-6-phenyl-1,3,5-triazine with Dicarboxylic Acids

Abstract

Structural studies on the cocrystals of 2,4-diamino-6-phenyl-1,3,5-triazine (dpt) with oxalic acid (Oxa), succinic acid (Suc), adipic acid (Adp), fumaric acid (Fum) and maleic acid (Mal) abbreviated as Oxa·2dpt (1), Suc·2dpt (2), Adp·2dpt (3), Fum·2dpt (4) and Mal·2dpt (5) have been carried out. The packing patterns of 1–4 are assembling of end capped dicarboxylic acids with lengths varying from 23 to 28 A. In the cocrystal 1 the oxalic acid molecules are involved in R 2 2 (9) and R 2 2 (6) type hydrogen bonds. The oxalic acid molecules have lateral orientation with respect to dpt, which reduces the length of the end-capped structure from a possible longitudinal orientation. It also makes difference from the longitudinal orientations of the dicarboxylic acids observed in the cocrystals 2–4. The structures of the cocrystals 2–4 are guided by conventional R 2 2 (8) type of interactions between a nitrogen and amine group of heterocycle with carboxylic acid groups. The cocrystal 5 has dimeric assemblies of dpt bridged by maleic acid molecules to form infinite zipper like structure. The structure of the cocrystals of 2,4-diamino-6-phenyl-1,3,5-triazine (dpt) with oxalic acid, succinic acid, adipic acid, fumaric acid are comprised of end capped subunits of length in the range of 23–28 A, which are comprised of one acid and two dpt molecules whereas cocrystal of dpt with maleic acid has assemblies of infinite zipper like structure.