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By incorporating phosphorus(III)-based anions into a polyoxometalate cage, a new type of tungsten-based unconventional Dawson-like cluster, [W18O56(HPIIIO3)2(H2O)2]8−, was isolated, in which the reaction of the two phosphite anions [HPO3]2− within the {W18O56} cage could be followed spectroscopically. As well as full X-ray crystallographic analysis, we studied the reactivity of the cluster using both solution-state NMR spectroscopy and mass spectrometry. These techniques show that the cluster undergoes a structural rearrangement in solution whereby the {HPO3} moieties dimerize to form a weakly interacting (O3PH⋅⋅⋅HPO3) moiety. In the crystalline state the cluster exhibits a thermally triggered oxidation of the two PIII template moieties to form PV centers (phosphite to phosphate), commensurate with the transformation of the cage into a Wells-Dawson {W18O54} cluster. [ABSTRACT FROM AUTHOR]

Dawson-like clusters {W18O56XO6} (X: I, Te) with localized redox active inner-cluster templates are characterized by cyclic voltammetry, UV and EPR spectroscopy, and DFT calculations. [ABSTRACT FROM AUTHOR]

K10Li14 [W36Si4O136Mn10(OH)4 (H2O)8] ·60H2O (I) and the isomeric cluster K10Li13.5Mn0.25 [W36Si4O136Mn10(OH)4 (H2O)8]·60H2O (II), which differs only in the positions of the Mn centers captured in the precursor fragments, are synthesized by reaction of K8[γ-SiW10O36] with MnCl2 in an aqueous LiCl solution under ambient conditions (pH 8.3, 13% yield). [ABSTRACT FROM AUTHOR]

(TEAH)5Na [H5W18O59(IO3)] ·5H2O (I; TEAH: (HO-CH2-CH2)3NH+), the first example of a polyoxometalate with encapsulated IO3-, is synthesized from an aqueous solution of Na2WO4, H5IO6, and TEAHCl (pH 1.3 adjusted with 6M HCl, reflux, 1 h; yield given in g). [ABSTRACT FROM AUTHOR]