| As a newly-identified functional molecule-based materials, metal-organiccomplex has been a focus of material chemistry due to their flexible tailoringstructures, charming topological networks as well as their fascinating potentialapplications in functional solid materials ions exchange, adsorption, catalysis, and thedevelopment of optical, electronic, and magnetic devices. However, controlling theassembly and solid state structure of the target compound in this area is still achallenge to chemists. The factors that governing the formation of the frameworks ofcomplexes include not only the size, conformation, structure and coordinationproperties of ligands and the inherent properties of metal ions, but also thetemperature of reaction, pH of reaction, the ratio of ligands and metal ions as well asthe way of cooling. On the other hand, the extended high-dimensional supramolecularmetal-organic frameworks can be obtained by linking multinuclear discrete subunitsor low-dimensional entities via non-covalent bonds interactions such as hydrogenbond andπ-πstacking. The aim of this thesis is the synthesis of new coordinationcompounds on the basis of three multi-topic N-containing ligands3-(2-pyridyl)pyrazole(pp), 1,3-di(4-pyridyl)propane (bpp),Dipyrido[3,2-d:2′,3′-f]quinoxaline(Dpq), and metal ions with mixed ligands(muti-topic N-/O-containing ligands). The study on synthetic conditions and rules forthese new compounds, topological analyses, and the exploration of relationshipsbetween structures and properties for these new compounds are also carried out.Eleven new coordination compounds have been synthesized on the basis ofhydrothermal technique and/or mixed solution synthesis methods and structurallycharacterized by elemental analyses, IR, TG and single crystal X-ray diffractions. Thethermal stabilities and fluorescent activity of most compounds have been studied.1. Four new compounds, namely, [Cd2(pp)4(3,5-DNBA)2]·H2O (1),[Cd2(bpp)2(DNBA)4] (2), [Zn(bpp)(DNBA)2] (3) {[Co2(bpp)2(DNBA)4H2O]·MDNBA}(4) were successfully obtained by introducing two multi-topic N-containing ligands(pp and bpp) and 3,5-dinitrobenzoic acid as the coligands. The results of investigationshow that the structure, conformation and coordination properties of ligands and the inherent properties of metal ions governed the structure of the complexes.2. Four new complexes, namely, [Zn(dpq)2Cl2] (5), [Cd(dpq)(ox)0.5Cl]n (6),[Zn2(Dpq)2(2,5-pda)2(H2O)2]·2H2O (7), and [Cd2(Dpq)2(2,5-pda)2]n·2H2O (8) havebeen prepared with two transition metals (ZnII, CdII) using Dpq and differentO-/Cl-containing ligands as mixed ligands. The results of investigation show that thestructure and coordination properties of ligands and the inherent properties of metalions governed the structure of the complexes. In addition, the fluorescent properties ofthese complexes have been studied.3. Three novel Cd(II) metal–organic frameworks, namely,[Cd(Dpq)(1,8-NDC)(H2O)2][Cd(Dpq)(1,8-NDC)]·2H2O (9),[Cd(Dpq)( 1,4-NDC)(H2O)] (10), and [Cd(Dpq)(2,6-NDC)] (11) have been obtainedon the mixed ligands Dpq and three structurally related naphthalene-dicarboxylateligands [1,8-naphthalene-dicarboxylate acid (1,8-H2NDC),1,4-naphthalene-dicarboxylate acid (1,4-H2NDC), and 2,6-naphthalene-dicarboxylateacid (2,6-H2NDC)]. Complex 1 is the left- and right-handed helical chains. Complex 2shows a 2D rectangular network (4,4). Complex 3 is a metal–organic frameworkswith distorted PtS-type 3D architecture. Comparing the structures of the thesecomplexes, we found that the introduction of organic acid with different coordinationmodes, the length, and angle may have significant effects on the formation anddimension of the resulting structures.
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