Carboxyl Phenoxy (iso) Acid Metal Complexes Synthesis And Structural Chemistry Research

In this thesis, 2- or 3-(4-carboxylatophenoxy) propionic acids were synthesized. Fifteen complexes have been prepared by the normal temperature or hydrothermal method by the reactions of 2- or 3-(4-carboxylatophenoxy) propionic acid with some metal salts. These complexes were structurally characterized by element analysis, IR, single crystal X-ray diffraction, and some of them were recorded by PL. The acidity of flexible carboxyl group is greater than that of the rigid carboxyl unit, and the coordination ability of the flexible carboxyl group is stronger than that of the rigid carboxyl unit. For example, when one proton was losed from the flexible carboxyl group, low dimensional complexes 2, 5, 13, 14 could be formed, while two protons were completely departed from the carboxyl groups, two high dimensional complexes 3, 15 were obtained. The 3-(4-carboxylatophenoxy)propionic acid displays monodentate, bidentate, tridentate, tetradentate, pentadentate and heptadentate coordination modes. The radius of metal ions may influence the geometry of the metal ions and the structure of coordination polymers. For example, the cadmium ions have monocapped octahedron, pentagonal bipyramid and monocapped triangular prism in one dimensional cadmium complexes 4, 5, 6, respectively. The zinc ions have pentagonal bipyramid in complex 2 and triangular prism in complex 3. The barium ions have square-antiprism in one dimensional complex 14 and tricapped triangular prism three dimensional complex 15, respectively. The porous structures can form between the adjacent chains relying on molecular weak interaction, such as in complexes 4, 5, 10 ,14, which were filled in the free p-hydroxybenzioc acid and water molecule, nitrate ions, DMF and five water cluster, two water clusters, respectively. Moreover, the geometry and the coordination modes of assistant ligands can give great impact on the final structure of complexes.