Synthesis,Structure Modulation And Supramolecular Isomerism Of Metal-Organie Coordination Compounds Based On Multi-carboxylic Ligands

Because of their intriguing structural diversity and potential applications in gas storage and separation, catalysis, luminescent materials, magnetism and molecular recognition and so on, the design and synthesis of new functional metal-organic complexes is one of the active research fields in coordination chemistry, supramolecular chemistry, crystal engineering in recent years. In this thesis, we try to synthesize novel coordination complexes by the use of different flexible carboxylate ligands or rigid carboxylate ligands to assemble with transitional metal ions or rare-earth metal ions. Here,14novel coordination complexes have been synthesized by the self-assembly of carboxylate ligands with metal ions. All complexes have been determined by single-crystal X-ray diffraction, elemental analyses, XRPD analysis, thermal analysis, fluorescence spectroscopy and infrared spectroscopy. There are following four chapters:Chapter I:A brief introduction of the development of metal-organic coordination complexes, supramolecular isomers and potential applications. The factors influencing the structure of the coordination complexes, such as solvent, metal ions etc, has also been introduced.Chapter II:Design and synthesis of lanthanide-organic frameworks based on flexible dicarboxylate ligand (H2L1). we synthesized six coordination complexes in this chapter:La2(H2O)2(EtOH)(DMF)2(L1)3·3DMF·3H2O (1), La2(H2O)4(L1)3·2H2O (2), La2(H2O)2(DMF)4(L1)3·2DMF·2H2O (3), Ce2(H2O)2(DMF)4(L1)3·2DMF·2H2O (4), Pr2(H2O)2(DMF)4(L1)3·2DMF·2H2O (5), Nd2(H2O)2(DMF)4(L1)3·2DMF·2H2O (6). Their crystal structures have been determined by X-ray diffraction. Complexes1,2and3are supramolecular isomers. More interestingly, complexes1-3are supramolecular isomers, in which complexes1and2were induced by reaction vessel. but complexes2and3were induced by reaction concentration. Complexes3,4,5and6are isostructural. Chapter Ⅲ:Assembly of transition metal complexes based on a flexible carboxylate ligand H3tci. Five coordination complexes have been synthesized in this chapter:(Me2NH2)Zn(tci)3·0.5DMF (7),(Me2NH2)Zn(tci)3·2DMF (8), Mn1.5(tci)(NMP)2·(NMP)2(9), Er2(tci)2(DMF)(H2O)·2DMF (10), Dy2(tci)2(H2O)2(11). Complexes7and8are solvent-induced supramolecular isomer. In particular, complex7is a2D kgd net, while complex8is a3D Ion net. Complexes7and9has the same topologies, while complexes10and11are3D porous frameworks with same topologies.Chapter Ⅳ:Self-assembly of zinc complexes based on1,3,5-benzenetricarboxylic acid. In this cahpter, we synthesized three complexes:(Me2NH2)Zn(BTC)(H2O)·DMF (12), Zn1.5(BTC)(H2O)1.79(μ3-O)·2DMA-2H2O (13), Zn2(BTC)(NO3)(DMA)3(14). Complex12is a three-dimensional porous metal-organic framework, which is a rutile topology composed by the triangular and distorted octahedral building blocks. Complex13, contains two different coordination environments of Zn ions, is a multi-node cage-like coordination polymer. In complex14, Zn (1)-O tetrahedra and Zn (2)-O octahedral units constructed a single chiral three-dimensional complex. Using different reaction concentration, we get complexes12and13; using different metallic salts Zn(OAc)2or Zn(NO3)2, we get complexes12and14.