Binary Hydroxy Acid Constructs Of Transition Metal Complexes Synthesis, Crystal Structure And Properties Of The Research

The design, assembly, structural characterization and properties of the coordination polymerbecome one of the hot research spots. Because the carboxyl groups of the carboxylic acids havemany kinds of coordination modes, a series of novel coordination polymers are formed throughthe reaction of the different types of carboxylic acid with transition metal ions. Thesecoordination polymers have displayed the attractive prospects in the field of catalysis, adsorption,optical, electromagnetic, ion exchange, and biological activity.The synthesis, structural characterization and properties of the transition metal complexeswith the dicarboxylic acid have been studied in the thesis. Thirteen new transition metalcomplexes have been synthesized by using3,4,5,6-tetrafluoro-phthalic acid and9,10-dihydroanthracene-9,10-endo-α, β-succinic acid as the primary ligands and the heterocyclic bases asauxiliary ligands through a liquid layer diffusion method at room temperature, the solventevaporation method and solvothermal synthesis method, and characterized by X-ray singlecrystal diffraction, infrared spectroscopy and elemental analysis. The crystal structures of13compounds have been resolved. The electrochemical properties of the representative complexeshave been studied.1. Ten novel transition metal complexes,[Co(tfpa)(pyra)2](1A),[Cd(tfpa)(im)2](2A),[Ni(tfpa)(1,10-phen)2](3A),[Ni(tfpa)(pyra)2](4A),[Cd(tfpa)(1,10-phen)2](5A),[Cd(tfpa)(2,2’-bipy)2](6A),[Cd(tfpa)(4,4’-bipy)2](7A),[Mn(tfpa)(4,4’-bipy)2](8A),[Cu(tfpa)(meim)2](9A), and [Cu(tfpa)(benzimi)2](10A), have been prepared by usingtetrafluorophthalic acid as the first ligand and heterocyclic base containing nitrogen atoms suchas pyrazole,2,2’-bipyridine, imidazole, benzimidazole,2-aimidazole,4,4’-bipyridine, and1,10-phenanthroline as the second ligand. Their single crystals are obtained by using the roomtemperature evaporation method or the liquid layer diffusion method. Their structures aredetermined by the X-ray single crystal diffraction. The Metal atoms in the complexes1A,2A,and4A are six-coordinated and have the distorted octahedral geometry; and one-dimensionalchain structure is formed through carboxylic acid ligand bridging metal ions.3A and5A aremononuclear metal complexes in which metal ions possess the distorted octahedral structureswith the monodentate-coordinated carboxylate and each structural unit connected into atwo-dimensional supramolecular structure through intermolecular hydrogen bonds.6A is adinuclear macro-cyclic complex in which the Cd is seven-coordinated distorted and has thepentagonal bipyramidal geometry. Carboxylic acids in7A and8A adopt monodentatecoordination mode. They formed two-dimensional lattice structure through the phthalate and4,4’-bipy bridges to metal ions.9A has a distorted tetrahedral configuration in which the carboxlate bridges the central copper ion and forms a one-dimensional chain.9A is furtherconnected into the three-dimensional supramolecule through the intermolecular hydrogen bonds.10A is the complex ion formed by the coordination of N atom of benzimidazole to copper ion.The electrochemical property of9A was determined by the cyclic voltammetry method.2.9,10-dihydro anthracene-9,10-endo-ɑ,-succinic acid was selected as the first ligandand2-methylimidazole and imidazole as the second ligand to synthesize3new coordinationcompounds,[Co(dasa-Me)(meim)2](1B),[Cd(dasa-Me)(meim)2](2B), and [Cd(dasa-Me)(im)2](3B), by solvothermal and liquid layer diffusion method. X-ray diffraction analysis showed thatone carboxyl of carboxylate ligand forms ester with methanol and the other carboxylate formscomplex with metal ion.1B is a tetrahedron structure and is connected into a two-dimensionalsupramolecular structure through the intermolecular hydrogen bonds.2B is a distortedoctahedron structure in which the coordination mode of the carboxyl group is bidentate chelatingand is connected into a two-dimensional supramolecular structure through the intermolecularhydrogen bonds.3B is a complex ion formed by the coordination of imidazole N to Cd. In3Bthe carboxylate anion as the balance ion is not coordinated to Cd.The synthesis, structural characterization and properties of the thirteen new transition metalcomplexes have been studied in the thesis.