The Study Of The Bridging Compounds Based On Keggin-type And Paratungstate-B

In this paper, the aim of this thesis is the synthesis of new framework compounds on the basis of polyoxometalates. The study on synthetic conditions and rules for these new compounds by utilizing metal ions and its organic chelating or linetype N-donor ligands complexes, and the exploration of relationships between structures and properties for these new compounds are also carried out.Seven new transation metal coordination hybrid compounds and six new metal cations bridging compounds have been synthesized on the basis of hydrothermal technique /or regular synthesis methods and structurally characterized by elemental analyses, IR, XRPD, TG and single crystal X-ray diffractions. The thermal stabilities, magnetic properties, Luminescence properties and electrochemical activities of these compounds have been studied.1. Four novel transation metal coordination hybrid compounds have been synthesized through the decoration or connection of transition metal ions based on the [AlW₁₂O₄₀]^5- polyanions. {Ag₃(2,2'-bipy)₂(4,4'-bipy)₂}{Ag(2,2'-bipy)₂}{Ag(2,2'-bipy)}[AlW₁₂O₄₀]·H₂O (1) [Ag(phen)₂]₃[Ag(phen)₃][AlW₁₂O₄₀]·H₅O₂ (2) {Co(2,2'-bipy)₃}₃{Co(H₂O)(2,2'-bipy)₂[AlW₁₂O₄₀]}2·H₂O (3) (H₂bpe){Cu(bpe)}{{Cu(bpe)}₂[AlW₁₂O₄₀]}·3H₂O (4)Under the hydrothermal condition, We have obtainded the infrequent {AlW12} species which is difficult to be obtained using the bench method. The results open up a door for the sample and availability synthesis method of the {AlW12} species.In research process, we found that the different transition metal ions and ligands with different configurations would impact the structure of the product as synthesised. The structure of compound 1 possess of silver-capped character. Five crystallographically independent Ag ions have four types of coordination geometry, this is infrequent in polyoxometalates chemistry. The trimeric {[Ag(phen)₂]₃}³⁺ cluster in compound 2 are rarely to extend into a three-dimensional supramolecular network. Recently, Hill's study result shows that the catalysis activity of the extend polyoxometalates decorated and connected by Ag+ ions is better than their matrix polyoxometalates. The successful synthesized of compounds 1 and 2 have shown that they will be significantly useful in catalysis. The structure feature of compound 3 is that three water molecules linearly arrange between the adjacent monosupporting {Co(H₂O)(2,2'-bipy)₂[AlW₁₂O₄₀]}^3- anions, leading to form the resulting three-dimensional supramolecular network by weak interactions. The structure feature of compound 4 is that a 3-D supramolecular network featuring 1-D rectangular channels formed.2. Introducing the mixed bpy ligands into polyoxotungstates, we have obtained three kinds of novel transation metal copper coordination hybrids compounds: {Cu₄^IICl(2,2'-bipy)₄(4,4'-bipy)₃(4,4'-Hbipy)₂[PMo₁₂O₄₀]}[PMo₁₂O₄₀]2·2H₂O (5) {Cu₂^I(2,2'-bipy)₂(4,4'-bipy)}{Cu_1.5^I(2,2'-bipy)(4,4'-bipy)}₂[BW₁₂O₄₀] (6) [Cu₂^I(2,2'-bipy)₂(4,4'-bipy)][Cu_1.5^I(2,2'-bipy)(4,4'-bipy)]₂[H₃W₁₂O₄₀] (7)Because mixed organic ligands can form the different transition metal subunit, which have different coordinate ability for different polyoxometals unit, which will result in the novel structure with different coordination enviroment between polyoxometals and transition metal complexes, and demonstrating that the hydrothermal method is the effective for the construction of novel structures.In compound 5, the dinuclear copper unit is formed by means of a Cu–Cl bond. This case is first observed in the POM system and shows a unique 2D architecture with dangling polyoxoanion clusters, such compounds may exhibit efficient photoinduced electron transfer. compound 6 is that the complex containing mixed organoamine ligands exhibits an unusual three-dimensional network. It is noteworthy the compound 2 represents the first 1D structure formed by ispolyoxotungstate building blocks [H₂W₁₂O₄₀]^6– and transition metal complex frameworks with mixed ligands.3. Six new inorganic compounds with extend structure have been synthesized on the basis of the various metals in the presence of ispolyoxotungstates. The structural transformation [W₁₀O₃₂]^4-→[H₂W₁₂O₄₂]^10- confirmed the previous prediction of Pope and offered a route for the preparation of paratungstate-based compounds. [Na₈(H₂O)₂₈)][Mn(H₂O)₂(H₂W₁₂O₄₂)]·4H₂O (8) [Zn₅(H₂O)₂₀(H₂W₁₂O₄₂)]·16H₂O (9) K[Na₅(H₂O)₆][Sr₂(H₂O)₆(H₂W₁₂O₄₂)]·18H₂O (10) (NH₄)₃[Na₅(H₂O)₁₇Cl]{[Na(H₂O)₄]₂[CeW₁₀O₃₆]}·6H₂O (11) (H₃O)₃[{K(H₂O)}₂{Na₂(H₂O)₈}₂(Na_0.5H₂O)₂(H₂W₁₂O₄₂)]·6H₂O (12) (H₃O)₂[{K(H₂O)₄}₂{Na₃(H₂O)₉}₂(H₂W₁₂O₄₂)]·2H₂O (13)The 2D layered structure of the compound 8 is formed by the interconnection of 1D [Mn(H₂O)₂(H₂W₁₂O₄₂)]_n^8- and [Na₈(H₂O)₂₈]_n⁸⁺chains. In the compound 9, theparatungstate ions are linked by [Zn₄(H₂O)₁₄]⁸⁺ units, leading to the formation of a 2D layer containing rhombic channels. Compound 10, paratungstate-B units act as six-dentate ligands coordinating to six Sr²⁺ ions. Interestingly, the strong involvement of the potassium and sodium counteractions leads the neighboring layers to tie together generating a 3D network containing two types of channels. Compound 11 represents the first extended structure based on the [Ce(W₅O₁₈)₂]^9- polyoxoanion. Compounds 12 and 13 were isolated from the acetate buffer solution containing decatungstate [W₁₀O₃₂]^4- at different reaction temperatures and exhibit different three-dimensional architectures with bridging sodium and potassium as countercations.