| Metal-organic frameworks (MOFs) have attracted great attention due to their diverse architectures and potential applications in adsorption separations, sensing, gas storage, and catalysis. Three 3(4)-bis(pyridylmethyl) phenyl and naphthalene diimide ligands (4-pmntd,4-pmpmd,3-pmpmd) reacted with various transition metals affording a series of complexes with structures varying from zero-dimension to three-dimensions. Various structure complexes have different properties , which help us understand the self-assembly of supramolecular complexes. All complexes have been characterized by single crystal analysis, IR, TGA, XPRD, EA, ESI-MS and NMR techniques, and their properties have also been determined. The dissertation includes four parts as follows:1. Assembly of a 1D coordination polymer through in situ formation of a new ligand by double C-C coupling on CHCl3 under solvothermal conditions involves cleavage of three C-Cl bonds and the formation of two new C-C bonds at the same carbon center. A radical reaction pathway has been proposed for the double C-C coupling on CHCl3, which leads to an unprecedented C-C bond formation. 2. A two-fold interpenetrating NdO network topology complex has been synthesized by complexing 4-bis(pyridylmethyl) phenyl diimide ligand (4-pmpmd) with Cu2+, which shows a dynamic behavior, directly visualized by single crystal to single crystal transformations On heating the crystals at 110 oC , an unusual change in the coordination number of the copper center was involved owing to the reversible removal of methanol molecules coordinated to CuII. The desolvated phase containing coordinatively unsaturated metal centers reveals selective sorption capabilities for CO2 gas and some alcohol solvents, which may be applied in the removal of CO2 from synthesis gas and flue gas mixtures.3. The synthesis of a 2-D 4(2).6(3).8 network new topology complex with 4-bis(pyridylmethyl) naphthalene diimide ligand (4-pmntd), which shows a dynamic behavior. When heated to 100℃, the coordinating methanol molecules of the crystal was removed, companying with the change of crystal colors, and afforded a coordinatively unsaturated complex, where Cu2+ leaving the axial positions free. The resulting complex only provides active sites for water, methanol and ethanol molecules, and the sorption order is water > methanol > ethanol. It also reveals selective sorption capabilities for CO2 gas and methanol solvent, which may be applied in the removal of CO2 from synthesis gas and flue gas mixtures.4. Three 3(4)-bis(pyridylmethyl) phenyl and naphthalene diimide ligands[ 4-pmpmd(L1),3-pmpmd(L2),4-pmntd(L3)] and its Mn(II), Cd(II), and Co(II) complexes have been synthesized and structurally characterized. In complexes 13, 16 and 19, neutral L1 ligand, adopting the Z-mode conformation, birdges two metal center with two nitrogen atom from a ligand. So complexes 13 and 16 show 1D chainlike structure, and 19 is three interpenetrating diamondoid networks structure. Different from L1, L2 ligand which takes on a Zt-mode conformation and serves as a monodentate ligand in 14 coordinates to one metal center with one nitrogen atom from a ligand, and the other nitrogen atom forming hydrogen-bonds assemble the mononuclear basic units into a 1D ribbon chain. However, in complex 17, L2 ligand adopts the Uc conformation to bridge two metal ions, leading to the formation of a single-stranded double helical chain structure. As to the L3 ligand,π???πstacking interactions between the naphthalene rings play a primary role in directing the assembled supramolecular complexes process. In complexes 15, 18 and 21, L3 ligand coordinates to one metal center with four ligands to form [M(L3)2] building blocks, which are connected into a (4,4) topological network sustained byπ???πstacking. Interestingly, when reacted with different metal salts, the L2 ligand can take on varied conformations to generate complexes 14 , 17 and 20 are discrete 0D, 1D single-stranded double helical chain and 2D (4, 4) topological network coordination structures, respectively. The results showed that the conformation and coordination mode of organic ligands and the coordination geometry of metal centers play an important role in determining the structure and topology of the complexes. Therefore, these large semirigid ditopic ligands can be rationally used to construct novel metal–organic frameworks with specific structure and properties, which may bring new insights and important impetus to crystal engineering. The luminescence properties of 17 and 18 were studied in the solid state at room temperature. To study the porosity of 19, the gas sorption properties were also measured. Complex 19 shows a highly selective sorption behavior towards CO2, which can be a promising candidate as adsorbents for CO2/N2 separations.
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