Sheldon epoxidation mechanism

Molecular hydrogen can reduce cyclic peroxo complexes, for example Reaction 30 (111), and Sheldon and Van Doom (33) had envisaged epoxide production via a similar process, Reaction 31. A mechanism based on such reactivity (with subsequent epoxide isomerization) is a possibility for our catalysis using H2/02, although Reaction 31 did not occur under mild conditions (33). Isolation of a related peroxometallocyclic rhodium complex, (Ph3As)2Rh[02C2(CN)4] + (92), allows for a testing of Reaction 31 at a Rh center. 

Key Words Ethylene oxide, Propylene oxide. Epoxybutene, Market, Isoamylene oxide. Cyclohexene oxide. Styrene oxide, Norbornene oxide. Epichlorohydrin, Epoxy resins, Carbamazepine, Terpenes, Limonene, a-Pinene, Fatty acid epoxides, Allyl epoxides, Sharpless epoxidation. Turnover frequency, Space time yield. Hydrogen peroxide, Polyoxometallates, Phase-transfer reagents, Methyltrioxorhenium (MTO), Fluorinated acetone, Alkylmetaborate esters. Alumina, Iminium salts, Porphyrins, Jacobsen-Katsuki oxidation, Salen, Peroxoacetic acid, P450 BM-3, Escherichia coli, lodosylbenzene, Oxometallacycle, DFT, Lewis acid mechanism, Metalladioxolane, Mimoun complex, Sheldon complex, Michaelis-Menten, Schiff bases. Redox mechanism. Oxygen-rebound mechanism, Spiro structure. 2008 Elsevier B.V. 

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