Syntheses, Structures And Characterization Of Modified Polyoxometalate

Applying in hydrothermal synthesis reactions, six novel polyoxometalate derivatives,has been synthesized, including three series, transition metal capped, main group metalcapped and transition metal supported. On the bases of X-ray structural analyses, it has beencharacterized by IR, XPS, EPR spectra and thermal analyses.Compound1represent the first example classical Keggin aluminotungstate heteropolyblue supported by three transition metal complex moieties, which further act as the neutralmolecular unit for the construction of the interesting classical distorted cubic (-Po) net.One non-classical metal-oxygen clusters has been synthesized from the system(NH4)3[P(Mo3O10]4XH2O–Cu(NO3)2–en. Compound2which has2D network structure, isbased on the standberg-type polyoxoanion [HP2Mo5O23]5-linked by the transition metalcomplex ion [Cu(en)2]2+bridges. The crystallographic water molecules and coordinationcation of Cu2+are embedded into the layer and act as―glue‖to reinforce the2D layersforming an overall3D supramolecular structure.Compounds3and4are isomorphic, has been hydrothermally synthesized from thesystem Sb2O3–H3PMo12O40–H2C2O4–dabco. The three-electron-reduced polyoxoanion is anovel bi-antimony capped pseudo-Keggin phosphomolybdate, in which the Sb atomexhibits novel hemidirected coordination geometry with coordination number4-Ψ-rhombicpyramidal {SbO4E} with the lone pair of electrons occupying axial position.The fundamental unit of compound5exhibits a mono-capped and bi-supported Kegginstructure, which further acts as the neutral molecular unit for the construction of theinteresting3D supramolecular network through hydrogen bonding and π···π stackinginteractions. The capped and supported units are the coordination cation of Cu2+. Compound6exhibits a bi-capped&bi-supported Keggin type Mo/V/O cluster, and the capped andsupported units are the {VO}2+groups and the coordination fragements of Zn2+,respectively.