Syntheses, Structures And Properties Of A Series Of Metal Tetrazole Coordination Ploymers By Hydro(solvo)thermal Syntheses

The high-connected metal-organic frameworks based on metal clusters are of great current interest because of intriguing topologies and possible applications in gas storage, catalysis and nonlinear optical materials. Recently, metal clusters in place of single metal centers have served as nodes in the construction of high-connected metal-organic frameworks. Compared with metal ions, metal clusters generally have larger sizes and more coordination sites but smaller steric hindrance when coordinated by organic ligands. On the other hand, metal-organic frameworks based on polynitrogen heterocycle linkers have attracted much attention. Among them, tetrazolates and their derivatives draw particular attention due to their rich coordination modes and interesting structures. Here we report the metal clusters based high-connected metal-organic frameworks constructed by 1H-tetrazole and three coordination polymers with tetrazolyi ligangs generated via in situ reaction. The dissertation is composed of three chapters. Chapter one is introduction. There are three parts. One is a brief introduction to metal clusters based high-connected metal-organic framework. The second briefly introduces the backgroud and recent progress of metal-tetrazole coordination polymers. In the third part, the significance and new results of the dissertation are outlined.In chapter two, five tetrazole-based (Htta) complexes, named {[Cu8O(tta)12](ClO4)2·2H2O) (1), [Cu6(tta)6Cl2(OH)4] (2), [Cu5Cl(tta)9] (3), [Cu4(tta)2Cl2] (4) and [Co(tta)(OH)] (5), were obtained by direct reaction of tetrazole with CuCl2/Co(OAc)2 under hydrothermal reaction conditions. Compound 1 has a perfect square planar-tetracoordinate oxygen in a tetracopper cluster based an eight-connected body-centered cubic coordination polymer. Compound 2 shows a 3-D network connected byμ3-tta ligands, in which each copper center adopts tetragonal pyramid coordination geometry. Compound 3 shows an interesting six-connected acs topological network constructed by{Cu8(tta)9} cluster units. Compound 4 contains 2-D layer which is composed of tetranuclear clusters{Cu4Cl2} connected by theμ4-tta. Compound 5 is a 3-D metal-organic framework with eight-connected body-centered cubic structure, in which the cobalt(Ⅱ) clusters and tta ligands act as nodes and lingks. Magnetic measurement conform that complexes 1,2 and 3 show antiferromagnetic behavior while compound 5 is characteristic of canted antiferromagnet.In chapter three, we describe three tetrazole coordination polymers [Zn2(4,5-Dtim)2·2H2O] (6), [Cd3(ox)2(atta)·H2O] (7), [Cu5Cl(Hbeta)(tta)2(ctta)] (8), synthesized by in situ cycloaddition reaction of 4,5-dicyanoimidazole, cyanoacetic acid, iminodiacetonitrile with sodium azide in the presence of ZnCl2, CdCl2 and CuCl2 as Lewis acid under hydro(solvo) reaction conditions. Photoluminescence studies reveal that the three coordination polymers exhibit strong blue fluorescent emissions in the solid state at room temperature.