A [Mo₂O₂S₂]-based ring system incorporating tartrate as the bridging ligand: synthesis, structure and catalytic activity of Cs₄[Mo₂O₂(μ-S)₂]₂(μ₄-tart)₂ (tart=[C₄H₂O₆]⁴⁻)

Abstract

Treatment of [Mo2S2O2(H2O)6]2+ with racemic tartaric acid (tartH4) in the presence of sodium hydroxide and cesium chloride in aqueous solution led to the isolation of a new tetra-molybdenum ring cluster Cs4[Mo2O2(μ-S)2]2(μ4-tart)2. The cyclic cluster polyanion consists of two dinuclear [Mo2O2(μ-S)2]2+ moieties and two bridging tart4− ligands. The cyclic polyoxothiomolybdate cluster, supported on the mesoporous silica SBA-15, was tested for heterogenerous catalysis in thiophene hydrodesulfurization.