Acidic aqueous solutions of the [Cp*MoO2(H2O)x]+ ion yield single crystals of the novel organometallic polyoxomolybdate via a slow protonolysis of the Mo–Cp* bond. This compound has subsequently been obtained selectively and in good yields from the combination of and four equivalents of under acidic conditions. The X-ray structure of is analogous to other hexanuclear polyoxometallate ions but is the most distorted so far reported according to the continuous symmetry measure, the inner (μ6-O)Mo6 core featuring a large displacement of the central oxygen atom toward the organometallic moieties and away from the inorganic ones.