Oxidation of tricarbonylmolybdacarborane. 2. Oxidative decarbonylation with various sulfur donors

Article abstract of DOI:10.1016/S0020-1693(98)00094-2

For the first time, the structure of the half-sandwich complex [(C₂B₉H₁₁)Mo(CO)₃]^2- (1) has been determined. The addition of sulfur donor ligands, such as aldrithiol ((C₅H₄NS)₂) and tetraethylthiuram disulfide ((Et₂NS)₂S₂), leads to the partial oxidative decarbonylation of 1 producing mixed half-sandwich complexes, [(C₂B₉H₁₁)Mo(CO)₂(S ₂CNEt₂)] · (PPN) (2·PPN) (PPN; bis-(triphenylphosphoranylidene)ammonium) and [(C₂B₉H₁₁)Mo(CO)₂(C ₅H₄NS)] · (NMe₄) (3·NMe4). These compounds were characterized both spectroscopically and structurally. Complexes 2 and 3 contain a Mo(II) center in a pseudo pyramidal geometry. Compound 1 · (NMe₄)₂ is fundamental in affording an entry into the chemistry of new molybdacarboranes with higher formal oxidation states.