| Supramolecular chemistry is a new branch of knowledge developed by the interaction of modern chemistry, material chemistry and life-science. It has been widely used in m- olecular absorption and separation, heterogeneous catalysis, ion transport, magnetism a- nd luminescent materials. Very recently, remarkable progress has been made in the area of supramolecular polymers. Many coordination compounds from zero to three-dimens- ional structures have been synthesized and characterized by chemists in the world. In th- is thesis, symmetrical carboxylic acid ligands containing double Schiff-base unit and be- nt ligands with ether linkage were synthesized. The coordination chemistry based on th- ese new ligands and metal ions was investigated. Totally 17 new coordination compoun- ds were prepared and fully characterized by IR, elemental analysis, and X-ray single-cr- ystal diffraction. In addition, we investigated the luminescent and molecular absorption and separation properties of some coordination compounds.I. The coordination chemistry based on pyridine ligands containing double Schiff-base with inorganic Cd(II), Co(II), Zn(II) salts has been investigated. Nine new coordination compounds, namely {[Co(L1)2]Cl2·2(CH2Cl2)}n (1), {[Co(L1)2]Cl2·2 (CH2Cl2)}n (2), {[Zn(L1)](SCN)2}n (3), {[Cd(L1)](SCN)2·0.5(CH2Cl2)}n (4), {[Cd (L3)1.5](NO3)2}n (5), {[Cd(L3)]Cl2}n (6), {[Co(L3)]Cl2}n (7), {[Cd(L3)(SCN)2]·CH2Cl2}n (8), {[Cd(L6)2](NO3)}n (9), were synthesized based on them, respectively. Their single crystal structures were investigated in the solid state. In addition, we investigated the adsorption and desorption properties of the coordination compound (9) for CH2Cl2, the separation properties for CH2Cl2 and CHCl3. All the process was characterized the by 1H NMR and PXRD. We also investigated the luminescent properties in the CH2Cl2 adsorption prosess.II. Coordination chemistry based on new Salen ligands was investigated, and four coordination compounds were obtained: {[Hg3(CuL7)]I6} (10), {[Cu3(CuL7)]I6} (11), {[Hg3(NiL7)]I6} (12), {[Hg3(NiL7)]Cl6} (13). The compounds 10, 11, 12, 13 were all mixed-metal supramolecular compounds synthesized by"two-step"method. The neutral single-metal ligands generated from the Salen ligands and Cu(II) or Ni(II) salts were designed and then acted with other metal salts to obtain four novel mixed-metal coordination compounds.III. Coordination chemistry based on 1, 3, 4-oxadiazole bridging asymmetrical ligands was investigated, and four coordination compounds were obtained: {[Cu2(L10)2] (acac)2} (14), {[Ag2(L15)2](BF4)·CH2Cl2} (15), {[Ag2(L15)2](PF4)·CH2Cl2} (16), {[Ag2(L15)2](SO3CF3)·CH2Cl2}(17).Their single crystal structures and luminesce- nt properties were investigated in the solid state.IV. Five-membered heterocyclic bridging Schiff-base ligands were synthesized and fully characterized by IR, 1H NMR and elemental analysis.This study demonstrated that bent ligands with ether linkage containing Schiff-base unite and five-membered heterocyclic ring can be used as precursors to bind transition metals, is in fact a new and efficient approach for synthesis of novel supramolecular systems with interesting chemical and physical properties. It provides a promising and convenient approach to access to the multifunctional materials for selected sorption, recognition, catalysis, and luminescence and magnets.
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