| Coordination polymers have recently attracted considerable interest, owing to their versatile framework topologies as well as their special properties, such as optical, electrical and magnetism properties. In addition, these materials may have many potential utilities in molecular recognition, catalysis, separation and molecular devices, so many researchers show great interest in studying complexes having new topological structures and special properties.In this thesis, by combining the ligands with transition metals we prepared a series of transition metal complexes of different dimensions and novel topological structures and these complexes were characterized through elemental analysis, IR, and X-ray diffraction analyses. Some compounds show strong photoluminescence and good thermal stability. The thesis consists of five chapters:In Chapter 1, we introduced the strategies of how to build coordination polymers and their potential utilities in material science.In Chapter 2, eight novel heteroaryl functionalized 1, 8-naphthyridine derivatives have been prepared by Pd(OAc)2/PPh3 catalyzed amination of chloronaphthyridine. The Pd-catalyzed reactions progress smoothly, the separation procedure was simple and yields are moderate. The coordination behavior of several 1, 8-naphthyridine derivatives was investigated, and it was found that 1, 8-naphthyridine derivatives can act as bidentate bridge ligands, and monodentate ligands to bind one or two metals. The transition metal coordination complexes of 1, 8-naphthyridine derivatives can form multi-dimensional supramolecules through various inter- and intramolecular weak bonds such as Ag…Ag interaction, Ag…pπinteraction, halogen bonds and hydrogen bonds.In Chapter 3, we have synthesized six new imidazolium hexachlorostannate compounds by simple methods. These compounds exhibit three dimensional layer structures for the presence of interand intramolecular weak interactions such as hydrogen bonds,π-πstacking. The structure motifs of these complexes depend on the size, symmetry, and the charge number of the organic cations. Because the imidazole derivatives are easily prepared and the structures can be easily tuned, it is believed that the organic-inorganic tin compounds with novel structures and functionalities can be expected by variation of the organic cations. In addition the compounds were thermally stable, and they may be used as novel organic-inorganic hybrid materials.In Chapter 4, we prepared eleven novel complexes from self-assembly of the corresponding metal salts with flexible ligands and their structures were fully characterized by IR, and x-ray diffraction analyses. The flexible ligands may adopt various conformations when coordinating with transition metals, and thus there were little studies on the construction of coordination polymers by using flexible ligands. One to three dimensional supramolecular aggregates were formed by reacting of alkyl bridged diimidazole derivatives with transition metals. X-ray diffraction analyses revealed that complexes [Zn(nba)2L6] (21) (L6 = 1, 4-bis(N-imidazolyl)butane, nba = p-nitrobenzoate), Ni(L6)(hba)2(MeOH)2]·2MeOH (22) (hba = p-hydroxybenzoate), and [Zn(hba)2(L9)]2·EtOH·3H2O (23) (L9 = bis(N-benzimidazolyl)methane) have 1D zigzag chain structure in which [Zn(nba)2], and [Ni(hba)2(MeOH)2] units are held together by L6 or L9 ligands. Complexes [Mn(L7)2(H2O)2]Cl2·2H2O (24) (L7= bis(N-imidazolyl)methane), [Fe(L7)2(NCS)2·2H2O] (25), and [Co(L7)2(H2O)2](sal)2·4H2O (26) (sal = salicylate) exhibit 1D double-stranded chain structures resulted from doubly bridged [Mn(L7)2(H2O)2], [Fe(NCS)2], and [Co(L7)2(H2O)2] cations, respectively. Complexes [Cd(L6)1.5(NCS)2] (27), [Cd(L6)2(NO3)2] (28), [Cd(L6)2(tos)2] (29) (tos=p-tolylsulfonate), and [Co2(L6)4(NCS)4]·4MeOH (30) have 2D grid network structures with (4, 4) topology. Complex 31 is a cationic polycatenane, and the nitrate anions occupy the triangular channels formed by the interpenetrated networks.The Cd complex 28 has a (4, 4) topology network structure in which the nitrate anions coordinated as monodentate ligands, whereas nickel complex 31 displays a three dimensional interpenetrated network structure with the nitrate as counter anion. For compounds 25, 27, and 30, the NCS- anions coordinated to the central metals via different mode, thus different structural compounds were formed. Complexes 27-30 with (4, 4) topology 2D grid network structures have different grids dimensions which is due to the different spacer lengths between the donating atoms. All these complexes are thermally stable. In the solid state all the d10 metal complexes (Zn and Cd) display strong emissions at room temperature, and thus these compounds may be used as candidates for novel functional material.In chapter 5, we used two structurally related flexible imidazolyl ligands (L6), and (L7) to react with Mn(Ⅱ), Cu(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), Cd(Ⅱ), and Co(Ⅱ) salts of aliphatic/aromatic dicarboxylic acids, we get a number of novel metal-organic coordination architectures. The complexes were characterized through X-ray diffraction, elemental analysis, and IR spectra. The thermal and emission properties were also studied. The different coordination modes of dicarboxylate anions due to their chain length, rigidity and diimidazolyl functionality lead to a wide range of different coordination structures. The coordination polymers exhibit 1D single chain, ladder, 2D sheet and 3D network structures. The aliphatic and aromatic dicarboxylates can adopt chelatingμ2, bridgingμ2, and chelating-bridgingμ3 coordination modes, or act as uncoordinated counter anions. L6, and L7 act as bidentate bridging ligands. The central metal ions are coordinated in N2O4, N4O2, N3O3, N2O3. and N2O5 fashions depending on the ancillary ligands. The structure motifs tell that we can get different network by utilizing flexible divergent diimine ligands and dicarboxylate as building block. In addition, flexible ligands assembling with transition metals did not definitely lead to the formation of 3D supermolecules. In all these complexes, dicarboxylate auxiliary ligands participate in hydrogen bonds, through these hydrogen bonds the supermolecular structures were stabilized. When dicarboxylate auxiliary ligands act as uncoordinated counteranions, they function as templating agents fixing water molecules around them, the number of water molecules around the dicarboxylates relies on the span of the dicarboxylate. The water molecules around the dicarboxylate anions form various water and oxygen rings. Complexes 43 ([Zn(imc)(L7)]·H2O, imc=iminodiacetate) and 45 ([Cd(L6)(male)]·H2O, male=maleate) were thermally inert, and in the solid state they have strong blue emissions at room temperature, these two compounds may be used as excellent candidates of blue-fluorescent materials.
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