Crystal structure of 1,3-bi(4-pyridyl)propane — 5-methyl-benzene- 1,3-dicarboxylic acid (1:1), C13H14N2 ·C9H8O4

Abstract

Source of materialAn ethanol solution of 1,3-bi(4-pyridyl)propane (bpp, 0.2 mmol) was added dropwise to astirred aqueous solution (12 ml) of 5-methyl-benzene-1,3-dicarboxylic acid (0.2 mmol) at atemperature of 333 K. The reaction mixture was then filtered and the filtrate allowed to stand for about two weeks until colorless single crystals were obtained. Chemical analysis -found: C, 69.88 %; H, 5.92 %; N, 7.30 %; calculated for C 22 H 22 N 2 O 14 :C,69.83 %; H, 5.86 %; N7.40 %. DiscussionIn the field of supramolecular chemistry, great interest has been focused on the crystal engineering of coordination frameworks due to their new topologies, intriguing architectures, intertwining phenomena, and potential applications [1][2][3][4][5][6][7][8][9][10]. Studies in this field have been focused on the design and construction of novel coordination frameworks and the relationships between their structures and properties. In this context, benzenedicarboxylic acid and its derivatives (such as 1,3-benzenedicarboxylic acid, 1,4-benzenedicarboxylic acid, 5-hydroxyisophthalic acid) are widely used as building blocks to link metal ions to produce metal-organic frameworks with interesting structures and properties. Furthermore, these ligands can act as both hydrogen-bond acceptors and hydrogen-bond donors to generate supramolecular topologies. In view of this, we report the molecular assembly of 1,3-bi(4-pyridyl)propane and 5-methylisophthalic acid in order to further understand the coordination chemistry of 1,3-benzenedicarboxylic acid and its derivatives. The title crystal structure comprises a1,3-bi(4-pyridyl)propane molecule and a5 -methyl-benzene-1,3-dicarboxylic acid molecule per asymmetric unit ( figure, top). Both of the carboxylate groups of the acid are protonated. There exist intermolecular hydrogen bonds between carboxylate oxygen atoms and nitrogen atoms of bpp (d(O···N) distances: 2.6298 and 2.618(2) Å,and bond angles of ∠O−H···N are 177.9°and 175.6°, respectively). Then, an extended one-dimensional chain along [010] is formed (figure, bottom).