Metal-organic coordination polymers based on imidazolyl- and benzimidazolyl-containing 4,4′-bipy type ligands

Two new semirigid ligands 2,2'-bis(imidazol-1-ylmethyl)-4,4'-bis(4-pyridyl)biphenyl(L1) and 2,2'-bis(benzimidazol-1-ylmethyl)-4,4'-bis(4-pyridyl)biphenyl(L2) were designed and synthesized. Six new coordination compounds, (Cd(L1)Br-2)(n) (1), [Cd(L1)(1,2-bdc)(H2O)H2O}, (2), (Zn(L1) (1,3-bdc).2.7H(2)O} (3), [Co(L1)(1,3-bdc).H2O),, (4), (1,2-bdc = 1,2-benzenedicarboxylate, 1,3-bdc = 1,3-benzenedicarboxylate, {Cd(L2)(2)(NO3)(2)center dot 2H(2)O) (5) and, [Ni(L2)(2)(H2O)(2)1(ClO4)(2)-3H(2)O (6) based on them were obtained and characterized by single-crystal X-ray diffraction methods. I is a 2D infinite spongy cushion-like network. In 2, two bridging 1,2-bdc anions chelate two neighboring Cd(II) atoms with their carboxylate groups to form a 1D double chain. 3 displays a 2D network in which the wavelike (Zn(1,3-bdc(2-))) chains are linked to each other by bidentate L1. 4 adopts a unique 3D framework, in which the coplanar (Co(1,3-bdc2-)) chains are connected to each other through tridentate Ll. 5 features a 1D double chain motif composed of a square bimetallic ring as the building block. 6 is mononuclear nickel complex. The photoluminescence properties of L1-L2, 1-3 and 5 were investigated, and all of them exhibit intense fluorescent emissions in the solid state at room temperature. (C) 2013 Elsevier B.V. All rights reserved.