| Over the past few years, coordination polymers have attracted much attention due to their potential applications in fields such as gas storage, separation, catalysis, magnetism and optical materials. However, it still remains a challenging task to explore effective synthetic strategies for the preparation of coordination polymers with expect structures. It has been well documented that mixed ligands system, especial the mult-carboxylate and bis(pyridyl) bridging ligands formed "layer-pillared" framework could easily control the shape and size by varying either or both mult-carboxylate and bis(pyridyl) linkers without changing the topology of the networks. On the other hand the mixed ligands system include more than one kind of ligands, so it have more chances to functionize the frameworks.Coordination polymers consist of metal ions/clusters and bridging organic linkers, which formed high regular and infinite frameworks by coordination bond. The frameworks of the coordination polymers are not only influenced by metal ions, ligands, but also related with solvent system, pH value, reaction temperature and the method of crystallization. Recently, many groups work on depth study of the influenced factors, hoping to provide a theoretical basis for the rational design and controlled preparation.In this thesis, two dicarboxylic acid ligands with different angles have been designed and synthesized. Many coordination polymers were then synthesized by these ligands with different transition metal ions to investigate the influence of the different coordination angles. In addition, we introduce the amide group to dicarboxylic acid ligands in order to enhance the gas storage ability and increase the number of catalytic sites. Because the C-N bond of the amide group could rotate, the ligands have presented a wealth of conformations, resulting in many novel structures.After synthesizing the complexes with only one kind of ligands, we start to researching the mult-carboxylate and bis(pyridyl) mixed linkers system. Luckly, we obtained a series of isostructure complexes with pillar of4,4’-bipyridine. In order to increase the channel size and porosity, we introduced the (E)-1,2-di(pyridin-4-yl)ethane (dpe) instead of the4.4’-bipyridine (bipy) to serve as the ’pillar’. Finally, new two complexes with high porosity without changing the topology of the networks were synthesized. After this research, we explored the influence of the flexibility of bis(pyridyl) linkers to skeleton frameworks. From the structures of these coordination polymers, we found that the length and flexibility of the bis(pyridyl) have significant influenced the final structures. When the flexibility increased in some degree,3D structures will change to2D frameworks.In the last part of the thesis, we have systematically studied the influence of pH values to the framework of coordination polymers. Because our reaction systems include dicarboxylic acid ligands, the pH values of the system will directly influence the degree of the Ligands deprotons, and further affect the frameworks. The higher pH values, the more degree of the deprotons, and less number of coordination water moleculars in the metal ions or clusters, so will form higher dimensional structures of coordination polymers.Except for researching the skeleton frameworks, the gas storage (N2, H2) of some3D complexes with permanent porosity have also been investigated. The results showed that these coordination polymers have a certain degree of gas storage ability. We also investigated the solid-state luminescence of some Zn(Ⅱ)、Cd(Ⅱ) complexes. Most of the complexes observed luminescence increasing compare with the ligands, but some of the complexes showing a significant reduction. The difference of the emission peaks intensity for these complexes mainly derives from the differences of the coordination mode of the ligands, the coordination environments of the metal ions, and so on. |
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