Synthesis, Structure And Magnetic Properties Of Pyrazinamide Complexes

A novel structure of the complex has broad application prospects in functionalmaterials and molecular recognition, thus becoming the focus of attention in recentyears. Pyrazinamide containing N, O elements is the polydentate organic ligands, ithas a variety of coordination modes and can coordinate with a variety of metal, soit conducive to formed complexes with novel structure. In this thesis, seven newcomplexes complexes was synthesized successfully with pyrazinamide as mainlyligand by changing the metal ion. The structure characterization was undertaken byinfrared （IR） spectroscopy, elemental analysis and X-ray crystallography. Mainwork is summarized below:The complex （1）[（C₉H₇N₆O）₄Co₃（H₂O）₂]（NO₃）₄·CH₃OH·6H₂O is amixed-valence trinuclear complex in the form of CoIII-CoII-CoIII, Two terminalcobalt （Ⅲ） atoms are slightly deviation from an ideal octahedron environment. thecentral high spin cobalt （Ⅱ） atom is six-coordinated. The structure of complex（2）[（C₁1H₈N₅O）₄Co₃（H₂O）₂]（NO₃）₄·6H₂O is similar to the complex （1）, and the CoIIcenter is magnetically isolated, the complex display signatures of slow magnetic,so it indicate that the complex is a single molecular magnets.（3）[（C₁1H₈N₅O）₂Co]（ClO₄）·2.5H₂O and （4）[（C₁1H₈N₅O）₂Co]（BF₄） are complexesof mononuclear cobalt（Ⅲ）.The complex （5）[Cu₂（ppcd）（ac）₂（H₂O）（OH）]₂·H₂O is connected via two1,1-μ-bridged acetate groups to form a tetranuclear copper discrete withcentrosymmetry strucuture. The copper（II） ion adopt five-coordinate environment.Magnetic susceptibility measurement revealed the quasi-diamagnetic characterof the complex associated with very strong magnetic coupling between thecopper（II） ions. The structure determination revealed that copper atoms in complex（6）[Cu（ppcdOCH₃）（H₂O）]ClO₄·H₂O are bridged by NCO units in an end-to-endfashion with the occurrence of a1D polymeric infinite chain along the crystallographic c-axis,there is a strong antiferromagnetic interaction within1-Dcopper chain. The complex（7）Cu₃（ppcd）₂（H₂O）₆（SO₄）₂is a one-dimensional （1-D）decker structure. Magnetic susceptibility measurement revealed that is typical of anintermediate intramolecular antiferromagnetic coupling in a copper（II） trimer...