MS2(Me2PC2H4PMe2)2 (M = Mo, W): Acid-base properties, proton transfer, and reversible protonolysis of sulfido ligands

The acid-base reactivity of MS2(dmpe)2, where M = Mo and W and dmpe = Me2PCH2CH2PMe2 is examined. Consistent with its ready protonation, complex M=Mo is methylated, and the use of excess MeOTf gives [MoS(OTf)(dmpe)2](super +) and Me2S in a rare example of double alkylation at a sulfido ligand.