The Polyoxovanadate-Based Carboxylate Derivative KH[VV(OH)O(OOC(CH)COO)]·nHO: Synthesis, Crystal Structure, and Catalysis for Oxidation of Sulfides.

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.