Addition of Diphenylacetylene to MoO₂S₂²⁻ in NH₃−CH₃OH Medium

The reaction of MoO2S22- with diphenylacetylene in a methanol ammonia solution gives the novel dianion [Mo2(O)2(μ-S)2(η2-S2)(η2-S2C2(C6H5)2)]2- characterized by X-ray diffraction, 1H and 13C NMR. A comparison of the addition of different alkynes to oxothiomolybdates is discussed.