Rapid, covalent addition of phosphine to dithiolene in a molybdenum tris(dithiolene). A new structural model for dimethyl sulfoxide reductase

Article abstract of DOI:10.1021/ic301031b

Triphenylphosphine (PPh₃) rapidly and reversibly adds to the bdt ligand in the molybdenum tris(dithiolene) complex Mo(tfd)₂(bdt) [tfd = S₂C₂(CF₃)₂; bdt = S ₂C₆H₄], turning chelating bdt into the monodentate zwitterionic ligand SC₆H₄SPPh₃. A second PPh₃ molecule fills the newly created open site in the crystallographically characterized product Mo(tfd)₂(SC ₆H₄SPPh₃)(PPh₃), which is a structural model for dimethyl sulfoxide (DMSO) reductase. While the complex is only a precatalyst for reduction of DMSO by PPh₃ (the initially low catalytic rate increases with time), Mo(tfd)₂(SMe₂) ₂ was found to be catalytically active without an induction period.