Syntheses, Structures And Properties Study On Complexes Based On Ligand Having Benzimidazole /amide Groups

Recent years,the metal organic coordination polymers have been attracted great attentions. It is not only the novel topology structures of the coordination polymers but also the potential application in many fields such as gas adsorption, ion adsorption and recognition, nonlinear optical materials, magnetic functional materials and drug carrier, photocatalysis, photoelectric conversion, catalytic asymmetric synthesis and so on. But, how to control the structure of metal organic coordination polymer with expected properties and the application value of complex, it is still a great challenge.Because, as we all know, through the hydrothermal method to synthesis the single crystal, the growth of single crystal influenced by various factors and ultimately get complexes with different structures, such as, temperature, solvent, PH value, as well as the counter ion and metal ions, coordination ability of organic ligand and so on.With these factors, however, many chemists found different strategies to obtain compounds with the expected structure. Through the methods and experiences of the previous reports, for our thesis research and obtain a series of valuable experimental data and results.In this paper, we had synthesized six organic ligands: first system: including hydroquinone as link unit containing phenol ether groups of semi-rigid neutral ligands L¹, L² and binary carboxylic acid ligands H₂L³.The other system, containing amide groups with piperazine as the links obtained flexible neutral ligand L⁴ and a tribasic-carboxylic acid ligand H_L and a ligand H_L with four carboxylic groups.By using the six organic ligands and transition metal ions of common nitrate, such as Co（NO₃）₂?6H₂O, Ni（NO₃）_?6H₂O, Zn（NO_）?6H2O, Cd（NO_）?4H₂O are introduced and different kinds of acid and neutral nitrogen auxiliary ligand by solvent hot method for the cultivation of the single crystal, finally we obtained 10complexes:[Cd（IPA）L²]_n?2H₂O（1）,[Co（IPA）L²]_n?2H₂O（2）,[Cd₂（OB）₂（L²）2]_n（3）,[Zn（PMDA）L²]_n（4）,[Zn（L³）]_n（5）,[Ni（L³）]_n（6）,[Co（L³）]_n（7）,[Cd₂（IPA）₂L⁴]_n?2CH₃CN（8）,[Cd₂（IPA）₂L⁴]_n?H₂O（9）,[ZnL⁴4（H₂O）?2NO₃]_n?2H₂O（10）（L²=1,4-bis（（1-（pyridin-3-ylmethyl）-1H-benzo[d]imidazol-2-yl）methoxy）benzene）,L³=,2’-（2,2’-（（1,4-phenylenebis（oxy））bis（methylene））bis（1H-benzo[d]imidazole-2,1-diyl））diacetic acid,L⁴=piperazine-1,4-diylbis（（4-（1H-imidazol-1yl）phenyl）methanone）,H₂IPA=isophthalic acid, H2 OB = 2,5-dihydrothiophene-2,5-dicarboxylic acid, PMDA =benzene-1,2,4,5-tetracarboxylic acid),Measured by X-ray single crystal diffraction respectively. There are different structures such as one dimension chain, the 2D network, 3D framework. The topology analysis for the structures shows that they have different topology structure. Characterized by the Fourier transformation infrared,X-ray powder diffraction and thermogravimetric analysis, at the same time also studied their solid ultraviolet absorption spectrum, solid fluorescence spectrum.