Functionalization of heteropolyanions-osmium and rhenium nitrido derivatives of Keggin- and Dawson-type polyoxotungstates: synthesis, characterization and multinuclear ((183)W, (15)N) NMR, EPR, IR, and UV/Vis fingerprints

Reaction of K(10)alpha(2)-P(2)W(17)O(61)] or K(10)alpha(1)-P(2)W(17)O(61)] or Bu(4)N]OsCl(4)N] in a water/methanol mixture, and subsequent precipitation with (Bu(4)N)Br provided alpha(2)-P(2)W(17)O(61){Os(VI)N}](7-) and alpha(1)-P(2)W(17)O(61){Os(VI)N}](7-) Dawson structures as tetrabutylammonium salts. Reactions of (Bu(4)N)(4)]alpha-H(3)PW(11)O(39)] with either ReCl(3)(N(2)Ph(2))(PPh(3))(2)] or Bu(4)N]ReCl(4)N] are alternatives to the synthesis of (Bu(4)N)(4)]alpha-PW(11)O(39){Re(VI)N}]. (183)W and (15)N NMR, EPR, IR, and UV-visible spectroscopies and cyclic voltammetry have been used to characterize these compounds and the corresponding (Bu(4)N)(4)]alpha-PW(11)O(39){Os(VI)N}] Keggin derivative.