An acetate-bridged Ru-substituted arsenotungstate [H N(CH ) ] [As W O {Ru (CH COO)} ]⋅22 H O (1) has been synthesized and structurally characterized. Four Ru atoms occupy the respective lacunary S2 sites of the crown-shaped polyanion [As W O ] , and each Ru atom is coordinated by one As atom and five μ -O atoms, comprising four from the S2 site and one from the acetate ligand. To the best of our knowledge, this coordination of the Ru atom, with an Ru-As bond length of 2.377(3)-2.387(3) Å, is unprecedented in polyoxometalate (POM) chemistry. Notably, 1 exhibits high efficiency, excellent selectivity, and good recyclability for the oxidation of sulfides with hydrogen peroxide (H O ). Catalytic oxidation of various sulfides in the presence of 1 gives superior conversion and selectivity for sulfones in acetonitrile, whereas sulfoxides are obtained in methanol.

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The high-nuclearity polyoxovanadate-based carboxylate derivative KH[VV(OH)O(OOC(CH)COO)]·nHO (1) has been successfully synthesized by conventional aqueous methods and structurally characterized. The [VV(OH)O(OOC(CH)COO)] polyanion is built up from three cages: one {V(OH)O} cage and two identical [(VO)(OOC(CH)COO)] cages. Of the three cages, the {V(OH)O} is a purely inorganic polyoxovanadate cluster, whereas each of the [(VO)(OOC(CH)COO)] cages is a vanadium-based organic-inorganic hybrid cluster framed via four adipate ligands linking simultaneously to two triangular {V} units. The two [(VO)(OOC(CH)COO)] cages are covalently attached to the central {V(OH)O} cage via V-O-V bonds in a linear arrangement, resulting in a {V}-based hybrid cluster skeleton. The catalytic properties of compound 1 for the oxidation of sulfides by tert-butyl hydroperoxide were investigated, and the result indicates that 1 exhibits excellent catalytic activity for the oxidation of sulfides under mild conditions.

A novel class of organophosphonate-based polyoxomolybdate derivatives, KH[Ln(HO){(MoO)(OPCHCOO)}]·23HO (Ln = Gd (1Gd), Tb (2Tb), Dy (3Dy)), have been fully investigated by a few characterization methods such as single-crystal X-ray crystallography, XRPD, elemental analysis, TGA, and IR spectra. The magnetic properties of 1Gd, 2Tb, and 3Dy were investigated, as well as the solid-state luminescence properties of 2Tb and 3Dy. The catalysis properties of 1Gd, 2Tb, and 3Dy for thioether oxidization have been investigated using hydrogen peroxide (HO) as an oxidant. The catalysis study demonstrated the efficient and selective conversion of various thioethers to their corresponding sulfones in excellent yields.

A monomeric tricobalt(II)-substituted phosphotungstate polyanion, [HPWOCo], is stabilized by the attachement of an organometallic group, {Mn(CO)}, for the first time. The resulting polyoxometalate-supported [Mn(CO)] complex (1) can be used as an efficient catalyst in the cycloaddition of CO with epoxides under mild reaction conditions with pyrrolidinium bromide as a cocatalyst. Besides, magnetic measurements show that the compound exhibits weaker ferromagnetic interactions at low temperature.