Three new 3D coordination polymers constructed by biphenyl-2,2′,4,4′-tetracarboxylic acid: Effect of metal ions and the second ligands

Three new coordination polymers with different architectures, {[Zn-2(bta)(2,2'-bipy)(2)]center dot H2O}(n) (1), {[Cd-2(bta)(2,2'-bipy)(2)(H2O)]center dot H2O}(n) (2) and [Cd-3(bta)(Hbiim)(2)(H(2)biim)](n) (3), where H(4)bta = biphenyl-2,2',4,4'-tetracarboxylic acid, 2,2'-bipy = 2,2'-bipyridine and H(2)biim = 1H,1'H-2,2'-biimidazole, have been obtained by the reactions of metal nitrates, H(4)bta, the second ligands and H2O under similar hydrothermal conditions. All the polymers are three-dimensional (3D) constructions with different networks, in which 1, 2 and 3 exhibit a (4(2).8(4))-pts, (4(2).6(3).8) sra and (4(16).6(5)) topology, respectively. The bta ligands in 1-3 adopt eta(6),mu(6)-hexadentate, eta(8),mu(5)-tetradentate and eta(10),mu(7)-decadaldentate coordination modes, respectively, and the corresponding angles of two benzene rings in the ligand of each compound are 45.96 degrees, 54.93 degrees and 52.50 degrees, respectively. This study indicates that the natures of metal ions and the second ligands are crucial factors for self-assemble of coordination polymers. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.