Synthesis, Characterization And Application Of The Novel Coordination Polymer With Pyridinecarboxylic Acid As Ligands

The coordination polymer is a kind of important organic/inorganic hybrid material which is a type of self-assembly formed by organic/inorganic ligands and metal ions. Coordination polymers have potential applications in the areas of luminescence, magnetism, porosity, catalysis, adsorption, molecule identification and chirality because of their structural diversities. In this thesis, five coordination polymers with novel sturcutres were hydrothermally synthesized. Sturcutre and thermal stabilization of the five kinds of coordination polymers were characterized by many kinds of analysis methods, such as element analysis, infrared spectra, X- ray single cyrstal diffraction and thermal gravity analysis. The aim of this paper is to study the rule of the self-assembly of coordination polymers synthesized hydrothermally, and the structure and the related performances of the coordination polymers.Firstly, the coordination polymers were synthesized by the reaction of the ligand 4-hydroxypyridine-2,6-dicarboxylic acid and transition metal ions Zn²⁺, Cu²⁺, Cd²⁺ under the conditions of hydrothermal synthesis. Three coordination polymers with novel structures {[Cd2(HCAM)2(H2O)4]·3.5H2O}n(1), [Cu(HCAM)(H2O)3]n(2)å'Œ{[Zn2(HCAM)2]·2H2O}n (3) were synthesized. The results are as follows: (a) There are two mental centers in {[Cd2(HCAM)2(H2O)4]·3.5H2O}n, which adopts one-dimensional staircase structure by carboxyl of 4-hydroxypyridine-2,6-dicarbo xylic acid and water molecules which is further linked by hydrogen bonds to form a 3-D metal-organic framework. (b) There is one mental centers in coordination polymer(2). The structures of (2) show that the unit are infinited three-dimensional metal-organic open framework. (c) There are two mental centers in {[Zn2(HCAM)2]·2H2O}n, which adopts two-dimensional grid structure by carboxyl of 4-hydroxypyridine-2,6-dicarboxylic acid.Coordination polymer [Cu(3,4-pydc)(H2O)2]n were synthesized using 3,4-pydc (pyridine-3,4-dicarboxylic acid) and transition metal ions Cu²⁺ by synthesized hydrothermally. The units of Cu(3,4-pydc)(H2O)2 are linked into a wonderful 2-D grid structure via the chelate carboxylate groups from the 3,4-pyridinedicarboxylic acid,and the layers are interconnected via hydrogen bonds interactions to yield a 3-D supramolecularThe self-assembly of 2,6-naphthalenedicarboxylic acid (2,6-NDC) with Co(II) ion under hydrothermal conditions gave a novel three-dimensional coordination polymer [Co(2,6-NDC)(1,10-phen)]n. The results are as follows: (a)The coordination polymer which showed that each Co(II) ion formed a 2-D reticular through carboxyl oxygen atoms from 2,6-NDC which is further linked byÏ€-Ï€* stacking interactions to form a 3-D framework. (b) Because of weak acidity and difficult dissolution ability of these dicarboxylic acid the conditions of hydrothermal synthesis are severe. Especially, pH value of the reaction system, reaction temperature, crystallization time and temperature-descent rate affect the crystal structure.The synthesis of diphenyl carbonate (DPC) by oxidative carbonylation of phenol using coordination polymers [Cu(3,4-pydc)(H2O)2]n and [Co(2,6-NDC)(1,10-phen)]n as a promoter was studied. This established a foundation for further study on the performance of the coordination polymer in DPC synthesis by oxidative carbonylation of phenol...