Synthesis and Characterization of Metal Complexes with Mixed 4-Imidazole-Containing Tripodal Ligand and Varied Dicarboxylic Acid

Six new metal-organic coordination polymers [Mn(H3L)(ox)]center dot H2O (1), [Zn-2(H2L)(pbdc)(mu(2)-OH)]center dot 2H(2)O (2), [Co(H3L)(obea)]center dot 3H(2)O (3), [Ni(H3L)(pbea)] (4), [Co(H3L)(pbea)(H2O)(2)] (5), and [Co-4(H2L)(2)(pbea)(3)] (6) were synthesized by reactions of the corresponding metal salt with rigid tripodal ligand 1,3,5-tri(1H-imidazol-4-yl)benzene (H3L) and different dicarboxylic acid of oxalic acid (H(2)ox), 1,4-benzenedicarboxylic acid (H(2)pbdc), 1,2-phenylenediacetic acid (H(2)obea), 1,4-phenylenediacetic acid (H(2)pbea), respectively. The results of X-ray crystallographic analysis indicate that 1 and 3 are two-dimensional (2D) networks with 6(3)-hcb topology, while 2 is (4,5)-connected three-dimensional (3D) net with Point (Schlafli) symbol of (4(2).5(2).7(2))(4(2).5(3).7(4).8). Complex 4 is a binodal (3,4)-connected 2D network with V2O5-type topology. Complexes 5 and 6 were obtained through controlling reaction temperature, 5 features a one-dimensional (1D) chain, whereas 6 is an unprecedented tetra-nodal (3,4)-connected 3D net with Point (Schlafli) symbol of (4.6(2).10(3))(4.6(2))(4.6(4).8)(2) attributable to the rich coordination modes of the ligands. The results of magnetic measurements showed that there are antiferromagnetic interactions in 1. Complex 2 exhibits intense light blue emission in the solid state at room temperature, while 3 shows water vapor adsorption property.