Synthesis and characterization of organophosphoryl polyoxotungstates [RP(O)]2Xn+W11O39(8−n)− (Xn+ = P5+, Si4+, Ge4+, Ga3+)

In the presence of n-Bu4NBr acting as phase-transfer reagent, n-Bu4N+ salts of organophosphoryl polyoxotungstate derivatives [RP(O)]2Xn+W11O39(8−n)− [R = PhCH2CH2P(O), X = P, Si; R = C6H11P(O); X = Ge, Ga] have been prepared and characterized by elemental analysis, i.r., 31P- and 183W-n.m.r. spectroscopy. According to the elemental analysis and spectroscopic data, the hybrid anions consist of an α-[XW11O39] framework on which are grafted two equivalent organophosphoryl groups through P—O—W bridges; these new species still retain the Keggin structure. The six-line 183W spectrum indicates that hybrid anions possess Cs symmetry in MeCN.