The Organic Amine-modified Molybdenum Oxide, Vanadium Oxide Clusters Of Hybrid Materials Synthesis And Characterization

In this thesis, the new progresses in synthesis and structure of polyoxometalate chemistry in resent years are summarized and a number of typical structures among them are analyzed. Based on the above research outcomes, we adopted soft molybdenum or vanadium compounds as raw materials, combined with the structure-directing role of organoamines, to synthesize novel organic-inorganic hybrid compounds by means of the medium-temperature hydrothermal technique and routine method. Some constructive and helpful results are obtained, and all the results are summarized as follows:1. A helical compound [HsNtCH2)2NH2(CH2)2NH3]2[Mo9O30] , is synthesized from Na2MoO4 and diethylenetriamine under acid condition by hydrothermal method, and characterized by single crystal X-ray diffraction, IR, ICP, elemental analysis and TGA/DTA analysis. The inorganic subunit [Mo9O30]6- of this compound possesses 21 screw axis, the most interesting feature of polyanion chain is that it is not only helical as a whole, but also when it is divided by the two screw axis into two strands, each still remains helical array. Furthermore, unlike the other reported helical compounds, the helix in this compound is constructed from only Mo-O unit.2. A chiral layered compound {[(phen)VIVO]2(VV2O5)(HPO4)}n is synthesized from NaVO3, HaPO4, FeCl2 and 1,10-phen by hydrothermal method , and characterized by single crystal X-ray diffraction, IR, ICP, and elemental analysis. In the structure of this compound, two nitrogen atoms of 1,10-phen are directly coordinated to the vanadium skeleton. Interestingly, the crystal structure consists of two types of chiral layers, one life-handed, the other right-handed, which lead to a racemic solid-state compound. In each layer, there coexist three distinct rings, described as 8-, 12-, 16-membered ring.3. A double chain compound [Fe(o-phen)MoO4]n is synthesized from Na2MoO4, FeCl2, 1,2-propanediamine, 1,10-phen by hydrothermal method, and characterized by single crystal X-ray diffraction, IR, ICP, elemental analysis and ESR. The structure of the compound exhibits one-dimensional chain constructed from four-polyhedral rings consisting of two {MoO4} tetrahedra and two {FeN2O3} hexahedra. Furthermore, there are no interactions of Mo-O-Mo bridging units, but the interactions of M-O-Molinkages.4. A new difunctionalized polyoxometalate [Bu4N]2[Mo6O17(NAr)2] is synthesized from 2,4-dimethylaniline, DCC and [Bu4N]2[Mo6O19] by routine method, and characterized by single crystal X-ray diffraction and UV-vis absorption spectra. A crystal structure determination revealed that the anion [Mo6O17(NAr)2]2- in this compound is linear, centrosymmetric anion with terminal amine groups. This is the first linear difunctionalized derivative of hexamolybdate building block gained from the synthetical method of Peng groups.