Studies On The Synthesis, Crystal Structures And Characterization Of Complexes Of 1,4,5,6-Tetrahydro-6-oxo-3-pyridazine Carboxylic Acid

In this dissertation, twenty new coordination complexes of 1,4,5,6-Tetrahydro-6-oxo-3- pyridazine carboxylic acid have been synthesized by the liquid method or hydrothermal method. They were studied by IR and single crystal X-ray diffraction methods. The thermogravimetric analyses of complexes (1), (2), (3), (7) and (8) were studied, and the magnetic analyses of complex (15), (16) and (17) was also studied.The ligand we used is 1,4,5,6-Tetrahydro-6-oxo-3-pyridazine carboxylic acid (Htopca), and it has several coordination modes in this dissertation, as follows:There are three chapters in this dissertation:Chapter one: The complexes of [Zn(topca)₂(H₂O)₂] (1), [Zn(topca)₂(H₂O)₂]·2H2O (2), [Cd(topca)₂(H₂O)₂] (4), [Co(topca)₂(H₂O)₂]·2H2O (5) and [Ni(topca)₂(H₂O)₂]·2H2O (6) were obtained by the reaction of Htopca and corresponding metallic salts. [Zn(topca)(2,2'-bipy)] (NO3) (3) was obtained by the reaction of Htopca, Zn(NO3)₂·6H2O and 2,2'-bipy. The complexes of {[Mn(topca)(H2O)₃](topca)·2H2O}n (7) and {[Mn(topca)(H2O)₃](ClO4)}n (8) were obtained by reaction of Htopca and different manganic salts. [Cu(topca)₂]·2H2O (9) and [Cu(topca)₂]·4H2O (10) were obtained by the reaction of Htopca and CuCl2·2H2O, while in different pH values. Complex (8) belongs to Orthorhombic, while others belong to monoclinic system, and space groups are P2(1)/n, P2(1)/n, P2(1)/c, P2(1)/n, P2(1)/c, P2(1)/c, Pc, Pna2(1), P2(1)/c, P2(1)/n, respectively.In complex (1), (2), (4), (5) and (6), M(II) ion is six-coordinated and then formed a distorted octahedron geometry, and ligands coordinate with M(II) ion via (a) in these complexes. In complex (3), Zn(II) is six-coordinated with N3O3 environment, one oxygen atom and one nitrogen atom from the ligand, two nitrogen atoms from 2,2'-bipy, and two oxygen atoms from water molecules. In complex (7) and (8), the ligands coordinate with Mn(II) ions via (b), and Mn(II) ions are connected to 1-D chain structure by bidentate bridging carboxyl O atoms. In complex (9) and (10), Cu(II) ion is four-coordinated and then formed a rectangle geometry. The complex (1)～(9) are assembled to 2-D network structure and (10) is assembled to 3-D network structure by hydrogen bonds. We also have studied thermogravimetric analyses of complex (1), (2), (3), (7) and (8).Chapter two: Complex [Ca(topca)₂(H₂O)₂]n (11) and [Pb(topca)₂(H₂O)₂]n (12) were obtained by the reaction of Htopca and corresponding metallic chlorides, while {[Bi(topca)₃(H₂O)]·H₂O}n (13) was obtained by the reaction of Htopca and Bi2O3. All the complexes belong to monoclinic system, and space groups are P2(1)/c.In complex (11), the ligand exists in the form of (c), and Ca(II) ion is eight-coordinated, and then formed a distorted square antiprismatic coordination polyhedron. In complex (12), the ligand exists in the form of (d), and Pb(II) ion is six-coordinated, and then formed a distorted octahedron geometry. Both in complex (11) and (12), each ligand links two metal centers and each metal center coordinates four ligands to form a 2-D network. In complex (13), the ligand exists in the forms of (a) and (b), and Bi(III) ion is eight-coordinated, and then formed a distorted square antiprism. The ligand is bridging and chelating tridentate mode in which the coordinated atoms are two carboxyl O atoms and one pyridazinly N atom. By bridging carboxyl O atoms, the complex (13) is connected to 1-D chain structure. Chapter three: Complex {[La(topca)₃(H₂O)₃]·2H₂O}n (14), {[Pr(topca)₃(H₂O)₃]·2H₂O}n (15), [Nd(topca)₃(H₂O)₂]n (16), [Sm(topca)₃(H₂O)₂]n (17), [Eu(topca)₃(H₂O)₃]·3H₂O (18) and [Gd(topca)₃(H₂O)₃]·3H₂O (19) were obtained by the reaction of Htopca and corresponding metallic chlorides. The pH values of the reaction systems of (14)～(17) are 5.5, while (18) and (19) are 3.5. Complex [Dy(topca)₃(H₂O)₃]·3.5H₂O (20) was obtained by the reaction of Htopca and Dy2O3.Complex (14)～(20) belong to monoclinic system, and space groups of (14) and(15) are Pc, (16) and(17) are P2(1)/c, and (18)～(20) are P2(1)/n. In complex (14)～(20), Ln(III) ion is nine-coordinated and then formed a distorted single-capped square antiprismatic geometry. In complex (14) and (15), the ligands exist in the forms of (a), (b) and (e), and in (16) and (17), the ligands coordinate with Ln(III) ions via (a) and (b). Complex (14)～(17) were connected to 1-D chain structure via the form of (b). In complex (18), (19) and (20), the ligands exist in the form of (a), and intermolecular hydrogen bonds link the complexe of (14)～(20) into 3-D network structures. The magnetic data indicates antiferromagnetic coupling between the metal ions in complex (15) and (16).