Design and construction of six coordination polymers with imidazole-4,5-dicarboxylate ligand

Abstract

Six new metal-organic frameworks based on a rigid multifunctional ligand imidazole 4,5-dicarboxylic acid (H(3)idc), namely, [Zn-3(mu(3)-idc)(mu(5)-idc)](n) (1), {[Zn-3(mu(3)-idc)(2)(H2O)(dpeten)](n)center dot 2H(2)O}(n) (2), [Zn(mu-Hidc)-( mu-obix)(0.5)](n) (3), [Zn-4(mu-Hidc)(4)(mu-mbix)(2)](n) (4), {[Cd-5(mu(5)-idc)(2)(mu(4)-Hidc)(2)(H2O)(2)]center dot 2H(2)O}(n) (5) and [Cd-2(mu(3)-Hidc)(2)(mu-obix)](n) (6) (H(3)idc = imidazole-4,5-dicarboxylic acid, obix = 1,2-bis(imidazol-1-yl-methyl)-benzene, mbix = 1,3-bis(imidazol-1-yl-methyl)-benzene and dpeten = 1,2-di(pyridin-4-yl)ethene), have been constructed under hydro(solvo)thermal conditions and structurally characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD) and thermal analyses (TG, DTA, DSC) techniques. In these compounds, the ligand, H(3)idc, exhibits different coordination modes, constructing various architectures by bridging a variety of metal ions or polynuclear clusters. All of these coordination polymers exhibited intense fluorescent emissions in the solid state at room temperature. Furthermore, topological properties were studied. (C) 2015 Elsevier B.V. All rights reserved.