| Design and properties of the supramolecular metal coordination complexes are involved in many fields including inorganic,organic,solid state chemistry and material chemistry etc.It is the integration of research with foundation and application and has becoming interesting and rapidly developing fields in recent 20 years.The one,two,or three dimensional complexes can be constructed owning to the coordination structure of metal cation and the variety coordination mode of the organic ligands.The research of the structures and properties of these novel systems can not only enrich the studies of the theory and the synthetic strategy,but also further extend the application prospect in electronic,optics,magnetics,catalysis and biology simulation.Today,the hydrothermal and solvothermal technique are being applied widely by various specialists from different branches of science including organic chemistry,biochemistry,biotechnology,food and nutrition, environmental safety,and so on.In critical or supercritical water and other solvents under solvothermal conditions,a more active reaction system is formed which can greatly enhance the self-assembly of the building blocks such as chains and rings.Therefore,the hydrothermal and solvothermal technique have been a subject of the intense research owing to its potential application in the field of the solid-state chemistry.This work is mainly focused on the designing new reactions,synthesizing new compounds using supramolecular synthetic strategy and gradually establishing relationship between the solvent and the structure.In this thesis, by using oxalate as the main ligand and organic components or inorganic cations as templates or structure-directing agents,adjusting reaction conditions and studying the influence of solvent on structures,we obtain a series of supramolecular coordination polymers with novel topology structures under hydrothermal and solvothermal conditions.Single crystal X-ray diffractions reveal that these novel transition metal coordination polymers have notable characteristics such as one-dimensional zigzag or ladder-like chain structures,discrete sandwich-like complexes and hydrogen-bonded layered structures as well as interpenetrating network.Also,the inorganic-organic hybrid oxalatophosphates and oxalatosulphates prepared hydrothermally have rich structural characteristics.Under hydrothermal conditions,the assembly of the oxalate and rigid 4,4'-bipyridine ligand with transition metal ions has resulted in three low-dimensional supramolecular coordination polymers,(H2bipy)2+.[Fe(Ⅱ) (C2O4)2(OH2)]2-.(4,4'-bipyH2)22+.[Fe(C2O4)2.2(H2O)]2-.(HC2O4)2-和(4,4'-dipyH2)2+ [V2O2(C2O4)3(4,4'-bipiridine)].2H2O.As the hydrogen-bonded linker,the diprotonated bipyridine ligands connect the adjacent metel oxalates,thus forming three dimensional supramolecular structures in all these three complexes.Also the assembly of oxalate and a flexible ethylenediamine ligand under hydrothermal conditions yields one dimensional zigzag chain, Ni3(en)3(ox)3·6H2O(1)and two dimensional layer structure Co(en)(ox)(2).The ethylenediamine ligand shows trans coordinating mode in 1 and anti coordinating mode in 2 which is first reported in controlling the coordination mode of the en ligand.By introducing the chiral phenyldimethylamine ligand, we also get a sandwich-like supramolecular chiral complex,(C8H12N)+2 [CoⅡ2(C2O4)3(H2O)4]2-.From the previous research,we have concluded some simple assembly rules for metal-organic supramolecular coordination complexes.Based on these works,we have introduced the inorganic phosphate and sulfate group into the metal oxalate and four supramolecular hybrid inorganic-organic materials K2Fe(C2O4)(HPO4)(OH2).H2O,2(H2bipy)2+.[Fe(Ⅲ) (C2O4)2(HPO4)(H2PO4)]4-,(C12H14N2)2+[Fe(Ⅱ)2(C2O4)(OH2)8]2+.2(SO4)2-and(H2bipy)2+. (Hbipy)+.[Fe([Ⅲ)Fe(Ⅱ)(C2O4)2(SO4)2]3-.H2O have been prepared under hydrothermal or solvothermal conditions.Employing inorganic molybdic acid as the building block,we also have successfully isolated an open-framework structure RbCo(ox)0.5(OH2)MoO4 and an interpenetrating network Fe3(ox) (4,4'-bipy)(MoO4)2.2H2O.The synthesis of the metal-organic coordination polymers and the inorganic-organic hybrid materials with novel topology is important for finding new phases,exploiting new route and opening application field for new materials.All of these supramolecular coordination polymers have been determined by single-crystal X-ray diffraction analyses,IR and thermogravimetric analyses.
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