Organic salts formed by 2,4,6-triaminopyrimidine and selected carboxylic acids via a variety of hydrogen bonds: Synthons cooperation, and crystal structures

• Key Words:2,4,6-triaminopyrimidine; Supramolecule; Self-assembly; Synthon
• Abstract:By using solvent evaporation method, 2,4,6-triaminopyrimidine (TAPI) is employed to crystallize with a variety of acids, including 3,5-dihydroxybenzoic acid (HDHBA), 3-nitrophthalic acid (H(2)NPA), 5-amino-2,4,6-triiodoisophthalic acid (H(2)ATIPIA), 2,5-dibromoterephthalic acid (H(2)DBTPA), 1,5-naphthalenedisulfonic acid (H(2)NDSA), sebacic acid (H(2)SA), 1,2,4-benzenetricarboxylic acid (H(3)BTA), and biphenyl-2,2',5,5'-tetracarboxylic acid (H(4)BPTA). In all eight complexes, protons are completely exchanged from 0 atom of acid to nitrogen of TAPI in 1, 3, 4, and, 5, partly transferred in 2, 6, 7, and 8. The crystal structure of all eight complexes exhibit that classical robust hydrogen bonds X-H...X (X = O/N) direct the molecular crystals to bind together in a stacking modes. Classical hydrogen bond N-H...O is participated in forming all eight organic salts, while hydrogen bonding O-H...O are found in constructing the diversity structures in salts 1, 2, 3, 4, 6, and 7. The analysis shows that some classical su-pramolecular synthons, such as I R-2(2)(8), V R-4(2)(12), and VI S(6), are observed again in the construction of hydrogen-bonding networks. In the formation of layered and reticular structure, strong hydrogen bonds between water molecules and ligands having well-refined hydrogen atoms have been considered. Water molecules play an important role in building supramolecular structures of 1, 2, 3, 4, 7, and 8. Moreover, salts 1-8 are further characterized and analyzed by element analysis, infrared radiation, thermogravi-metric analysis, proton nuclear magnetic resonance spectra, and mass spectra. (C) 2017 Elsevier B.V. All rights reserved.
• Volume:1136
• Issue:
• Translation or Not:no