Syntheses, Structures And Properties Of Coordination Polymers Based On Flexible Aromatic Polycarboxylic Acids

The design and construction of new functional coordination polymers have been one of the most intensive research topics in coordination chemistry, supramolecular chemistry and crystal engineering due to their novel topological structures and potential applications in the optical, electrical, magnetism, molecular recognition and catalytic fields. The dissertation is aimed to synthesize porous coordination polymers by the reactions of Zn, Co, Cd and Mn metal ions with three new kinds of flexible aromatic polycarboxylic acids.8coordination polymers were prepared and characterized by elemental analyses, X-ray single/powder crystal diffraction, thermal gravimetric analyses, luminescence analyses and gas absorption measurements. The influences of metals, ligands and solvents on the assembly of these coordination polymers have been systematically discussed. This dissertation includes the following five chapters:Chapter1, Introduction. A brief introduction of the background was given. The synthesis strategies and progresses on Metal-Organic Frameworks (MOFs) were discussed. In addition, the aim and the main results of this work have been outlined.Chapter2, Syntheses, structures and properties of coordination polymers based on flexible aromatic polycarboxylic acids. Three novel coordination polymers based on flexible quadricarboxylate ligand5,5’-(1,4-phenylenebis(methylene))bis(oxy)diisophthalic acid (H4L) were obtained solvothermally and characterized.[Zn(H2L)(H2O)2] is a two-dimensional (2D) network with sql/Shubnikov topology.[Co2(H3L)2(H2L)(H2O)2]·5H2O is a one-dimensional (ID) zigzag chain-like polymer which form an extensive hydrogen bonding3D network. Compound3possesses a rare (4,8)-connected flu (CaF2) net and permanent porosities. In these complexes, the ligand H4L exhibits diverse coordination configurations and modes owing to its flexibility. Complexes1and3exhibit strong photoluminescent behaviors.Chapter3, Solvent induced synthesis of zinc(II) and manganese(II) coordination polymers with a flexible aromatic tetracarboxylic acid. By using a5,5’-(biphenyl-4,4’-diylbis(methylene))bis(oxy)diisophthalic acid (H4L) flexible aromatic quadricarboxylate ligand, four novel coordination polymers were obtained solvothermally and characterized. Compound [Zn2(L)]-CH3CN,4give rod packing of pcu type and elliptical channels of7.7x8.4A2. Compound [Zn4(L)2(H2O)4]-5H2O,5possesses a3D open framework with a doubly-interpenetrated sra net. Compound [Mn2(L)(H2O)2]·2H2O,6is built from trigonal-bipyramidal binuclear Mn2(OOC)3units and octadentate L ligands, forming a binodal5,5-connected43.66.8net. Compound [Mn(H2L)(DMA)(H2O)]-(DMA)(H2O),7is a2D layered structure made of4-connecting mononuclear Mn atoms and half-deprotonated L ligands. N2gas adsorption measurements at77K showed that compounds1,2and4possess permanent porosities.Chapter4, A coordination polymer of Cd constructed from a flexible aromatic hexacrboxylic acid. A novel coordination polymers based on flexible aromatic hexacrboxylic acid5,5’,5"-(2,4,6-trimethylbenzene-1,3,5-triyl) tris(methylene)tris(oxy)triisophthalic acid (H6L) has been synthesized and characterized.[Cd4(L)2(H20)8]·5H20(8) is a two-dimensional sheet-like polymer which forms an extensive hydrogen bonding3D network.Chapter5, Conclusion and outlook. The main achievements and conclusions in this thesis were summarized. The further research plan in this project has also been proposed.