Pyridine Diketone, More Aromatic Carboxylic Acid Coordination Polymer Synthesis, Structure And Properties Of The Research

Recently, the design and synthesis of intriguing structures, such as:polynuclear structure, porous structure, winding, interpenetrating, etc., have become a hot spot in the coordination chemistry field. Usually, they are significant potential application materials in the field of magnetism, gas adsorption, molecular sieves, and catalysis. Therefore,1,3-(2-pyridyl)-propane-1,3-diketone and3,3’,5,5’-biphenyl tetracarboxylic acid are selected as main ligands. Under the guidance of the crystal self-assembly engineering theory,12coordination polymers have been synthesized by adjusting the solvent system, pH value, reaction temperature, compensating ion, molar ratio of metal and ligand.Two complexes with1,3-(pyridin-2-yl)-propane-1,3-diketone are synthesized with the method of evaperating and diffusion. Complex1has a rod-shaped polynuclear chain with hexacoordinating Cd atoms bridged by oxygen,μ2-Cl and μ3-Cl; complex2is a tetranuclear oligomer. In general, supramolecular architectures are constructed through hydrogen-bonding interactions. In1, the channel between chains is filled with lattice molecules, and it shows luminescence.3,3’,5,5’-biphenyl tetracarboxylic acid is selected as the main ligand, nitrogen-containing chelating and bridging ligand as auxiliary ligands, with transition metal ions, to construct10coordination polymers hydrothermally. Carboxyl displays four coordination modes of chelating, cis-cis bridging bidentate, cis-anti bridging bidentate, chelating-bridge, and present in different combinations. Complexes3,4,6and7possess3D porous structure, and the effective porosity via Platon are16.2%,20.7%,63.5%,17.7%(removal of guest molecules), whose skeletons are stable to321℃,335℃,295℃,146℃. The fluorescence emission peak of3-6,10lie in purple visible region, which are expected prospects in the field of fluorescent material.