We report the synthesis, structural, and electronic characterization of the theoretically predicted, but experimentally elusive δ-isomer of the Keggin polyanion. A family of δ-Keggin polyoxoanions of the general formula, (TEA)HpNaq [H2M12(XO4)O33(TEA)]rH2O where p, q, r = [2,3,8] for 1 and [4,1,4] for 2 were isolated by the reaction of tungstate(VI) and vanadium(V) with triethanolammonium ions ...

Keggin-type heteropolyacid cesium salts have been regarded as potential candidates for heterogeneous catalytic reactions. This review describes the success of heteropolyacids (Cs-HPA salts) efficient catalysts in various synthesis processes. The Cs-HPA can be synthesized solid through metathesis a solution containing precursor HPA and another soluble Cs salt, which will give salt precipitate. A...

Keggin heteropolyacids (HPAs) are metal–oxygen clusters with strong Bronsted acidity. The conversion of HPAs to metal salts can result in Lewis acidity, improving their performance oxidation reactions. In this review, the main routes for synthesis Keggin-type salts, as well use catalysts processes a plethora substrates, such monoterpenes, olefins, aldehydes, terpene alcohols, and aromatics, des...

H [PV Mo O ] catalyzed oxidation of thiols to related disulfides under microwave irradiation(MW). 5 2 10 40 Hydrogen Peroxide as an oxidizing reagent under mild conditions carried out this reaction. This system provides an efficient convenient and practical method for the syntheses of symmetrical disulfides. In this work, the comparisons among the Keggin and Dawson type polyoxometalates are add...

The involvement of water in the selective oxidation MAL to MAA over a pure Keggin-type H3PMoO12O40 catalyst was investigated using an in situ DRIFTS reactor coupled with mass spectrometer for first time elucidate reaction pathway associated water.