%0 Journal Article
%T Crystal Structure and Thermal Behavior of Two New Supramolecular Complexes Templated with 1,2,4,5-Benzenetetracarboxylic Acid
%A Ling-Ling Gao
%A Yan Liu
%A Xu-Yan Lv
%A Jian-Feng Liu
%A Tuo-Ping Hu
%J International Journal of Inorganic Chemistry
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/291682
%X Templated coordination polymers [Ni(H2O)4(bipy)](BTA)0.5¡¤H2O (1) and [Co(H2O)4(bipy)](BTA)0.5¡¤H2O (2) (bipy£¿=£¿4,4¡ä-Bipyridine, H4BTA£¿=£¿1,2,4,5-Benzenetetracarboxylic Acid) were synthesized and characterized by single-crystal X-ray diffraction, powder diffraction, elemental analysis, IR, and thermogravimetric analysis. Both of complexes 1 and 2 are monoclinic crystal system, C2/c space group, and isostructural. The unit of the structure, the metal ion is coordinated by four water molecules and two bipy molecules, is a slightly distorted octahedral configuration, and the carboxyl group from BTA4- ion doesn't coordinate with the metal ion, the H-bonding interactions further connect the mononuclear molecules to generate a 3D supramolecular complex. 1. Introduction Coordination polymers are currently of considerable interest and importance because of the scope they offer for the generation by design of new materials with a range of potentially useful properties, such as magnetism, adsorption, ion exchange, and catalysis [1]. Self-assembly by intermolecular H-bonding and/or aromatic stacking interactions is an effective way on constructing functional supramolecular complex [2, 3]. Therefore, we have constructed coordination polymers based on the H4BTA ligand and transition metal ions by self-assembly method. So far, a mass of coordination polymers constructed by 1,2,4,5-benzenetetracarboxylic acid (H4BTA) have been reported, but studies on H4BTA as a guest molecule are less reported [4]. The results of previous research show that auxiliary ligands such as 4,4¡ä-bipyridine, 2,2¡ä-bipyridine play important role in constructing the complexes with unexpected architectures [5¨C12]. So, in this paper, we have constructed two supramolecular complexes with H4BTA as a templating agent and bipy as the auxiliary ligand: [Ni(H2O)4(bipy)](BTA)0.5¡¤H2O (1) and [Co(H2O)4(bipy)](BTA)0.5¡¤H2O (2), and the phase purity of the crystalline products was confirmed by powder X-ray diffraction (PXRD, shown in£¿£¿Figures 5s and 6s Supplementary Material available online at http://dx.doi.org/10.1155/2012/291682). 2. Experimental 2.1. Materials and General Methods All the reagents were commercially available and used without further purification. Distilled water was used throughout. Elemental (C, H, and N) analyses were performed on a CE-440 (Leeman labs) analyzer. Thermal gravimetric analysis (TGA) was performed on a PerkinElmer TGA 7 instrument in the temperature range of 25¨C700¡ãC at a heating rate of 10¡ãC/min under air atmosphere. IR spectra were recorded as KBr pellets on a FTIR-8400
%U http://www.hindawi.com/journals/ijic/2012/291682/