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

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)(2)S-2), leads to the partial oxidative decarbonylation of 1 producing mixed half-sandwich complexes, [(C2B9H11)Mo(CO)(2)(S2CNEt2)].(PPN) (2.PPN) (PPN; bis-(triphenylphosphoranylidene)ammonium) and [(C2B9H11)Mo(Co)(2)(C5H4NS)].(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. (C) 1998 Elsevier Science S.A. All rights reserved.