ESSAYS ON ORGANOMETALLIC CHEMISTRY .7. LABORATORY CURIOSITIES OF YESTERDAY, CATALYSTS OF TOMORROW - ORGANOMETALLIC OXIDES

A systematic investigation of organorhenium- and organoosmium oxides, following the initial discovery of trioxo(eta(5)-pentamethyl-cyclopentadienyl)rhenium(VII) in 1984 by Herrmann, Serrano and Beck, has yielded a plethora of high-oxidation-state organometallics. The key compound methyltrioxorhenium(VII) is now easily accessible and has displayed a surprisingly broad range of catalytic activities, most notably in olefin metathesis, olefin epoxidation, and aromatic oxidation (vitamin K-3). In this context, general problems related to synthesis and reactivity, to structure and bonding, as well as to thermal and photochemical stability were tackled and solved. Organometallic oxides can also serve as structurally well-defined molecular or polymeric precursor compounds for the synthesis of inorganic oxide, the formation of rhenium trioxide being the first example to result from the polymer route.