| In this thesis, we study the construction of a series of organic-inorganic hybrid compounds based on the classical Wells-Dawson and Keggin type polyoxometalate building blocks and different kinds of rigid N-donor organic ligands and flexible bis(triazole) ligands with different length, investigate the synthetic conditions and rules for these compounds, analyse the influence of the distance of coordination sites, the length of the ligands and the ratio of transition metal to ligand. The relationship between structures and properties for these new compounds are also carried out.Twenty-eight new organic-inorganic hybrid compounds based on polyoxometalate building blocks have been synthesized under hydrothermal conditions, and structurally characterized by elemental analyses, IR, TG, XPRD, XPS and single crystal X-ray diffractions. The photoluminescence properties and electrochemical properties of these compounds have been studied.1. Five new polyoxometalate-based derivatives have been designed, synthesized and characterized, through using funtional Wells-Dawson building block and different rigid symmetrical and unsymmetrical N-donor ligands: [Zn(phen)2(H2O)2][{Zn(phen)2}{Zn(phen)2(H2O)}{P2W18O62}]·8H2O (1) [Cd(phen)2(H2O)2][{Cd(phen)2}{Cd(phen)(H2O)3}{P2W18O62}]·4H2O (2) [Cu(2,2'-bpy)3]2[Cu(2,2'-bpy)2]2[P2W18O62] (3) [2,2'-bpy]8[Fe(2,2'-bpy)3]8[P2W18O62]4·9H2O (4) [Zn(phen)2(ppy)][{Zn(phen)2}{Zn(phen)2(H2O)}{P2W18O62}]·2H2O (5)Compounds 1 and 2 were synthesized under similar conditions except for selecting different transition metal ions, which can form 1D structure through the linkage of Zn/Cd ions. Compounds 3 and 4 are discrete supramolecular structures. When rigid symmetrical mix-organic ligands 1,10-phenanthroline and 2-(5-phenylpyridin-2-yl)pyridine) (ppy) are adopted, compound 5 was obtained, which has low dimension owing to big volume of ppy ligand.2. One novel discrete copper-capped compound and two 1D chain compounds have been synthesized based on Keggin type polyoxometalate building blocks, through tunning Cu-rigid organic subunits: [Cu2I(DF)2H2O][HPMo10VIMo2VO40{CuII(DF)}] (6) {[Cu4I(cppy)4][PMo7VIMo5VO40(VIVO)2]}·2H2O (7) {[Cu4I(cppy)4] [SiMo8VIMo4VO40(VIVO)2]}·2H2O (8)We have attained a new compound 6 through utilizing rigid ligand 4,5-diazafluoren-9-one, which has longer distance between two N-donors compared with other nomal bidentate chelate ligands. Compound 6 is composed of copper-capped anions and discrete copper dimer. Compound 7 with tetranuclear copper circuits as connectors was synthesized through using unsymmetrical ligand 4-(5-(4-chlorophenyl)pyridin-2-yl)pyridine (cppy).3.Six new compounds based on Wells-Dawson building block have been synthesized and characterized through tunning different transition metals, different valence of metal ions and the type of flexible ligands: (H3btb)[Fe(btb)3(P2W18O62)]·4H2O (9) [Cu6(btp)3(P2W18O62)]·3H2O (10)[Cu6(btb)3((P2W18O62)]·2H2O (11) [Cu3(btb)6(P2W18O62)]·6H2O (12)[Cu3(btx)5.5((P2W18O62)]·4H2O (13)[Cu3(bbtz)4(P2W18O62)]·7H2O (14)Compound 9 exhibits a 1D chain structure connected by Fe-1,4-bis(1,2,4-triazol-1-y1)butane (btb) complex. When tuned the–(CH2)n– length of flexible ligands and the ratio of metal to ligand, we have attained a series of high dimensional and high connection compounds 10–13, which show the highest connectivity of reported Wells-Dawson anions. Through replacing alkyl to phenyl between the bis(triazole), we have obtained compound 14, which exhibits a 3D framework.4.Thirteen novel compounds based on Keggin building blocks have been synthesized through changing the valence of transition metals and the type of flexible ligands: [Cu4(H2O)4(bte)2(HPMoVI10MoV2O40)]·2H2O (15)[Cu(btb)][Cu2(btb)2(PMo12O40)] (16)[Cu5(btx)4(PMo10VIMo2VO40)] (17)[Cu4I(bte)4(SiW12O40)] (18)[Cu2II(bte)4(SiW12O40)]·4H2O (19)[Cu4I(btb)2(SiW12O40)]·2H2O (20)[Cu2II(btb)4(SiW12O40)]·2H2O (21)[Cu6(bbtz)6(HPMo12O40)]·2H2O (22)[Cu6(bbtz)6(HPW12O40)]·2H2O (23)[Zn2(bte)4(SiMo12O40)]·2H2O (24)[Zn2(btp)4(SiMo12O40)] (25) [Zn2(btb)4(SiMo12O40)] (26)[Zn2(btx)4(SiMo12O40)] (27)Compounds 15–17 have been synthesized through using three ligands 1,2-bis(1,2,4-triazol-1-yl)ethane (bte), 1,4-bis(1,2,4-triazol-1-y1)butane (btb) and 1,6-bis(1,2,4-triazol-1-y1)hexane (btx), which have different length of–(CH2)n–. The dimensionalities of these three compounds are rised along with the increase of length of–(CH2)n– of flexible ligands, 1D chains in 15, 2D layers in 16 and a 3D interpenetrating structure in 17. The organonitrogen species act as not only ligands but also reductants under hydrothermal conditions, which can reduce Cu2+ to Cu+ with multiple coordination modes. Therefore, we have tunned the ratio of copper to ligands and compounds 18 and 19, 20 and 21 are obtained. Compounds 22 and 23 are attained with two-fold interpenetrated 3D frameworks through using 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (bbtz). Compounds 24?27 were synthesized under identical conditions except for selecting flexible ligands with different length, which show an anion-templated 1D chain structure for 24 and also anion-templated different 2D layer structures for 25–27.5.We tried to unite the rigid and flexible ligands to modify the Keggin polyoxometalate and one novle compound has been obtained: [Cu6(trz)2(bbtz)2(SiW12O40)] (28)Compound 28 is a 3D framework containing rigid and flexible mixed organic ligands, which can exert the merits of stability and big steric hindrance for rigid ligands and flexibility for flexible ligands to obtain novel compounds.
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