Metal-organic open frameworks with one-dimension channels assembled with pyridine 2,6-dicarboxylic acid and N-containing auxiliary ligands: Syntheses, crystal structures, and physical characterization

摘要

Four new complexes, {[Mn(imH)(2)(pdc)]center dot H2O}(n) (1), [Zn-2(pdc)(2)(H2O)(5)]center dot 2H(2)O (2), [Zn(imH)(2)(pdc)]center dot H2O (3), {[Zn-2(pdc)(2)(bpy)(H2O)(2)]center dot 5H(2)O}(n) (4) [imH = imidazole pdc = pyridine 2,6-dicarboxylate, bpy = 4,4'-bipyridine] have been synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR, PXRD, single-crystal X-ray diffraction and thermogravimetric analyses. All the four complexes display a three-dimensional (3D) open framework with one-dimensional (1D) channels that are filled with lattice water molecules. Particularly, in 4, the lattice water molecules form an infinite water chain. Both 1 and 4 consist of 1D polymeric chains. While 2 contains a dinuclear Zn(II) unit, and 3 is a mononuclear complex. Further, the result of thermal analysis of 1 and 2 shows the robustness of the overall supramolecular three-dimensional architecture. Complexes 1, 3, and 4 exhibit strong fluorescent emissions in the solid state at room temperature and could be significant in the field of photoactive materials.