Oxo Complexes of Tungstenocene via Oxidation of (W(Eta(5)-C5H5)2(OCH3) (CH3)) and Related Reactions: Synthesis, Structural Characterization, and Photodisproportionation of the Spin Paired d(1)-d(1) Oxo Bridged Dimer ((W(Eta(5)-C5H5)2(CH3))2(Mu-O))2(+) and Synthesis and Charaterization of the d(0) Terminal Oxo Complex (W(Eta(5)-C5H5)2(O)(CH3))(+)

There has been remarkable growth throughout the 1980s in the chemistry of transition metal oxo complexes. Interest in what had been regarded as a mature area was rekindled in part by the recognition of the role of the oxo functionality as a spectator ligand in catalytic alkene metathesis, and has been fueled by developments in the chemistry of transition metal porphyrin oxo complexes including their roles in hydrocarbon oxidations and in alkene epoxidation and hydroxylation reactions, by continuing rapid evolution of our understanding of biologically relevent oxo transfer reactions, by extraordinary advances in the use of oxo complexes as catalysts for alkene hydroxylation and epoxidation, and most recently, by the remarkable catalystic activity demonstrated by high valent rehenium oxo alkyls. These development have been paralleled by significant advances in the syntheses of oxo complexes, including the preparations of low valent oxo complexes and of high valent oxo alkyl complexes, and marked extentions of the rational synthesis of organometallic oxo complexes.