Coordination chemistry studies the formation, structure and properties of coordination compounds in which a metal center is bonded to ligands through coordination bonds. In this diploma thesis, the coordination chemistry of analogues of quinaldic acid with zinc(II) ions was investigated. Deprotonated quinoline-2,4-dicarboxylic acid and kynurenic acid were used as ligands, since the presence of multiple donor atoms enables different coordination modes toward the metal center.
The experimental part included the synthesis of coordination compounds under different reaction conditions, namely at room temperature, under reflux conditions and under solvothermal conditions in an autoclave. In reactions with quinoline-2,4-dicarboxylic acid, the same product, [Zn(2,4-dquin)2(CH3OH)2], was obtained under all conditions, where 2,4-dquin– represents the deprotonated form of the acid. During the reaction in an autoclave, single crystals suitable for single-crystal X-ray diffraction analysis were obtained. In reactions with kynurenic acid, different products were formed, including the coordination polymer [Zn(kyn)2]n·n(CH3OH) (kyn– represents the deprotonated form of the acid) and an unidentified compound A.
The prepared compounds were characterized by infrared spectroscopy, CHN elemental analysis and single-crystal X-ray diffraction analysis. The results provided insight into ligand coordination, compound composition and their structural characteristics.
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