New two-dimensional metal-organic networks constructed from 1,2,4,5-benzenetetracarboxylate and chelate ligands

Two novel nickel coordination polymers [Ni-2(2,2'-bipy)(2)(OH)(2)(H(2)bteC)(3n) (1) and [Ni-2(1,10'-phen)(2)(H2O)(2)(btec)](n) (2) (btec = 1,2,4,5-benzenetetracarboxylate) have been hydrothermally synthesized and characterized by elemental analyses, IR and XPS spectra, TG analysis, X-ray powder diffraction, and single crystal X-ray diffraction. Crystal data for 1: C90H66N12O30Ni6, monoclinic P2(1/c), a = 10.905(2) Angstrom, b = 18.006(4) Angstrom, c = 20.551(4) Angstrom, beta = 94.91(3)degrees, Z = 2. Crystal data for 2: C34H22N4O10Ni2, monoclinic P2(1/n), a = 10. 122(2) Angstrom, b = 9.3106(19) Angstrom, c = 15.690(3) Angstrom, = 92.03(3)degrees, Z = 2. Compound 1 exhibits a novel one-dimensional chainlike structure, in which the dinuclear Ni centers are linked by the btec ligands. Furthermore, the adjacent chains are linked into a 2-D wavelike layer via the strong OH...O hydrogen bonding interactions. Compound 2 possesses an unusual two-dimensional steplike network with interesting rhombic grids. Both compounds exhibit unprecedented metal-organic ligand construction modes in {M/btec/L} (M = transition metal; L = chelate ligands) systems. The magnetic behaviors of compounds 1 and 2 have been studied.