Selective Oxidations Catalyzed by Dioxo(porphyrinato)-ruthenium(VI) Species
Rajapakse, N., James, B.R., and David Dolphin
New Developments in Selective Oxidations, Centi, G. and Triffiro, F. Eds. Elsevier Science, Amsterdam
The complexes trans-Ru(porp)(O)2, where porp = the dianion of 5,10,15,20-tetramesitylporphyrin (TMP) or 5,10,15,20-tetra(2,6-dichloro- phenyl)porphyrin (OCP) , are readily formed in benzene by treatment of the Ru(II) bis(acetonitrile) precursors with O2 or air. Such dioxo species in solution utilize both oxygen atoms for oxygenation of thioethers to sulfoxides, phenol to hydroquinone, and (as noted by other groups) olefins to epoxides; 2-propanol is also dehydrogenated to give acetone. Catalytic O2-oxygenation has been demonstrated for thioether and olefinic substrates.