Synthesis and structural characterisation of an unusual tetranuclear oxomolybdenum( VI ) complex of dihydroxybenzoquinone, [Mo ₄ O ₁₀ (O ₄ C ₆ H ₂ ) ₂ ] ²– , and a comparison with the mononuclear chloranilate complex [MoO ₂ (HO ₄ C ₆ Cl ₂ )(O ₄ C ₆ Cl ₂ )] ¹–

While reaction of the sterically encumbered chloranil group with (Mo2O7)2– yields the mononuclear species [MoO2(L)(LH)]1–(L = C6O4Cl2), dihydroxylbenzoquinone under similar conditions yields the tetranuclear cluster [(Mo2O5)2(C6H2O4)]2–, a species with magnetically coupled semiquinone ligands.