Crystal structures of salts and cocrystal of 1,3,5-triazine derivatives with thiophene carboxylic acid derivatives: an investigation on supramolecular interactions

Abstract

Present work gives an account of different types of non covalent interactions encountered in the supramolecular architectures of new salts and cocrystal formed between derivatives of 1,3,5-triazine and thiophene carboxylic acid. The novel salts formed between derivatives of thiophene carboxylic acid and 1,3,5-triazine are 2, 4-diamino-6-methyl-1,3,5-triazin-1-ium 5-carboxythiophene-2-carboxylate monohydrate, C4H8N5+·C6H3O4S1−·H2O (I) and 2,4-diamino-6-methyl-1,3,5-triazin-1-ium 3-bromothiophene-2-carboxylate monohydrate, C4H8N5+·C5H2O2S1Br 1 − ·H2O (II). The new cocrystal is a 1:1 cocrystal formed between 2,4-diamine-6-phenyl-1,3,5-triazine and 2,5-dichlorothiophene-3-carboxylic acid, C9H9N5·C5H2O2S1Cl2 (III). The newly synthesized salts (I and II) and cocrystal (III) have been characterized by single-crystal X-ray diffraction. Supramolecular heterosynthons, homosynthons observed via N–H···O, N–H···N and O–H···N hydrogen bonds are also discussed. Anion···π interaction between carboxylate oxygen and aromatic rings of thiophene and triazine are observed in salt (I). π···π interaction is present between thiophene and triazine rings in salt (II). R 2 2 (8) ring motif is formed in cocrystal (III) via N–H···O and O–H···N hydrogen bonds. Further stabilisation of cocrystal (III) via Cl···O, Cl···Cl interactions as well as π···π interactions (triazine···triazine rings and triazine···phenyl rings) are also investigated.