Syntheses And Self-Asembly Of Rigid And Semirigid Five-Membered Heterocyclic Bridging Ligands And Symmetric Fulvene Ligands

The chemistry of organic-inorganic coordination polymers has recently becomearea of increasing interest. Self-assembly of organic ligands and inorganic metal ionsis one of the most efficient and widely used approaches for the construction oforganic-inorganic composite materials. In the thesis, a series of symmetric fulveneligands and rigid bent 1, 3, 4-oxadiazole-bridging ligands were synthesized. Thecoordination chemistry of these novel ligands with transition metal ions wasinvestigated. In addition, two semirigid Schiff-base-containing 1, 3, 4-oxadiazole-bridging ligands have been designed and synthesized. The coordination chemistrybased on them with metal ions was investigated too. Totally 13 new coordinationcompounds were prepared by solution reactions and fully characterized by IR, 1HNMR, elemental analysis and single-crystal X-ray diffraction.A. Four new Ag(I)-containing coordination polymeric compounds generated from thesymmetric fulvene ligands(L1 and L2) and AgX (X = ClO₄^-and SbF₆^-) have beensynthesized: [Ag(L1)](SbF₆)(1), [Ag_0.5(L1)](SbF₆)_0.5·0.5(C₆H₆)(2), [Ag(L2)](SbF₆)·0.5(C₆H₆)·H₂O(3), [Ag(L2)]ClO₄(4). Their single crystal structures wereinvestigated in the solid state.B. Four new Ag(I)-containing coordination polymeric compounds based on rigid bent1, 3, 4-oxadiazole bridging ligands(L3) and AgX (X = SO₃CF₃^-, ClO₄^-, SbF₆^-andBF₄^-) have been synthesized: [Ag₂(L3)] (SO₃CF₃)₂(5), [Ag(L3)]ClO₄(6), [Ag(L3)]SbF₆(7), [Ag(L3)]BF₄(8). Their single crystal structures were investi-gated in thesolid state.C. Two new macrocyclic coordination compounds generated from semirigid Schiff-base-containing 1, 3, 4-oxadiazole bridging ligand (L4) and MII(Ac)2 (M= Ni, Cu)[Ni(L4)]·CH2Cl2(9), [Cu(L4)]·CH2Cl2(12). Two unusual AgI-NiII2NiIII2 cluster-containing mixed-mental and mixed-valence coordination polymers, generatedfrom nickel-macrocyclic complex and silver ion by metal exchange, have beensynthesized: [Ag2Ni(L4)](ClO4)2.5(10), [Ag2Ni(L4)] (BF4)2.5(11). In addition,another Ag(I)-containing coordination polymeric compounds, generated fromligend (L5) and AgSO3CF3, have been synthesized: Ag(L5)(SO3CF3)?CHCl3(13).Their single crystal structures were investigated in the solid state.D. The luminescent properties of organic ligands L1-L4 and polymeric compounds(5-8 and 9-12) were investigated both in the solid state and solution. The resultsshow that the emission wavelength and intensity of free organic molecules wereaffected significantly by their incorporation into the metal -containing polymericcompounds.E. Host-Guest Chemistry of Compound 9 and 12 were investigated. The experi-mental result shows that 9 and 12 exhibits a clear affinity for CH2Cl2 molecule,and can reversibly desorb and re-absorb this guest molecules at room temperature.It is worthy pointing out that the single crystals can be kept thoughout the wholeconversion process.F. The electrical conductive properties of polymeric complexes 6 were investigated.The primary result indicates that these compounds behave as typical semi-conductors.The results reported herein demonstrate that the use of fulvene ligands , rigid orsemrigid bent five-membered heterocyclic bridging ligands as precursors to bindtransition metal ions, is in fact a new and efficient approach for synthesis of novelsupramolecular networks with interesting physical properties.