Synthesis and characterization of metal complexes with mixed 4-imidazole-containing tripodal ligand and varied dicarboxylic acid

摘要

Six new metal-organic coordination polymers [Mn(H _3L)(ox)] ?H _2O (1), [Zn _2(H _2L)(pbdc) (μ _2-OH)]?2H _2O (2), [Co(H _3L)(obea)] ?3H _2O (3), [Ni(H _3L)(pbea)] (4), [Co(H _3L)(pbea)(H _2O) _2] (5), and [Co _4(H _2L) _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 (H _3L) and different dicarboxylic acid of oxalic acid (H _2ox), 1,4-benzenedicarboxylic acid (H _2pbdc), 1,2-phenylenediacetic acid (H _2obea), 1,4-phenylenediacetic acid (H _2pbea), 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 (Schl?fli) 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 V _2O _5-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 (Schl?fli) 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.