Synthesis, Crystal Structures And Gas Adsorptions Of Novel Metal-Organic Coordination Complexes Based On Large Multi-carboxylate Ligands Through Solvothermal And Room-Temperature Biphasic Synthesis

Nowdays the design and synthesis of new functional metal-organic coordination complexes is an active and difficult research filed for their potential applications in photoelectricity, magnetism, catalysis, gas adsorption, separation and so on. Metal-organic coordination complexes are adjustable comparing with traditional zeolites. Besides the external conditions such as the solvent, temperature, pH etc., the ligand conformation and the coordination geometries of metal ions or metal clusters have a crucial impact on the final structure of MOFs. The semi-direactional synthesis of MOFs can be realized through the connecting the metal ions or metal cluster and the ligand as the spacer which can be pre-designed. It is important to control the conditions for obtaining the desired MOFs.In recent years, planar aromatic carboxylate ligands have been widely researched due to their varieties of coordination modes and strong coordination ability. Based on the influence of the ligand,.we designed and synthesized a series of nonplanar aromatic multi-carboxylate ligands with a big rigid structure (H3L1, H6L2, H4L3, H4L4, H4L5, H6L6, H6L7, H6L8, H4L9).16novel MOFs were obtained through the assembly reactions between the synthesized ligands and Zn2+, Cd2+, Cu2+. All complexes have been characterized by single-crystal X-ray diffraction, elemental analyses, thermal analysis, XRPD analysis, fluorescence spectroscopy, circular dichrosim and gas adsorption. The contents of this dissertation are as follows:1. H3L1is nonplanar for the three methyls of the central benzene ring. Complexes1,2, and3were obtained by the assembly of H3L1and Zn2+. These three complexes are supramolecular isomerisms driven by CH---π interactions among the two dimensional honeycomb layers, while complexe2is homochiral crystallization from an achiral ligand through chiral inducement.2. Two porous MOFs (4,5) have been synthesized by polycatenation between the bilayers which are connected by two different pyridine ligands. By comparing the adsorption results, the length of the second ligand affects the size of pores of MOFs. 3. Complexes6-9is the assembly of metal ions and ligands (H6L2, H4L3, H4L4) which are big rigid aromatic structures. Their structures and topologies have been described and analyzed. They are all porous MOFs with polyhedrons or cages.4. Four different silicon-based ligand have been designed and synthesized. We synthesize and characterize two Cd(Ⅱ)-H4L5, Cu-H6L6, Cu-H6L7and Cu-H6L8coordination polymers. The solvent system plays an important role in modulating the final structures. Complexe10and11present2D (4,4) net and (4,8)-connected3D porous framework with flu topology. Complexes12,13and14show the same (3,24)-connected3D porous framework with rht topology. We mainly invesitigate the effect of the modified groups on the central silicon atom on the gas adsorption among the complexes12-14with the same structure.5. A novel Metal-organic nanotube (15) and a1D coordination polymer (16) with large water clusters are obtained and characterized via a new synthetic approach: phase-transfer catalyst supported, room-temperature biphasic synthesis. The new nanotubular material (15) is non-interpenetrating because of the large template of [Cu(py)4Cl·Cl] and the steric hindrance effect of the methyl groups of H4L9. It is interesting to observe that1D novel water tape with an8-membered ring as the basic unit reside in complexe16.