Epoxidation hexafluoroacetone peroxide

Hexafluoroacetone and hydrogen peroxide in buffered aqueous solution can epoxidize alkenes and allylic alcohols.101 N, Af-Dialkylpiperidin-4-one salts are also good catalysts for epoxidation.102 The polar effect of the quaternary nitrogen enhances the... 

Recent literature refers to the stereoselective and asymmetric epoxidation of allylic alcohols with organoaluminium peroxides. PhaSiOOH epoxidizes olefins with a stereoselectivity similar to that with peracid. Reports have been made of a-substituted hydroperoxides (acids, esters, ketones, amides, and nitriles) as effective epoxidizing reagents and the application of hexachloroacetone, tetrachloracetone, and hexafluoroacetone hydroperoxide, as well as the HaOa-Vilsmeier reagent system. ... 

M. C. A. van Vliet, I. W. C. E. Arends, R. A. Sheldon, Hexafluoroacetone in hexafluoro-2-propanol A highly active medium for epoxidation with aqueous hydrogen peroxide, Synlett (2001) 1305. 

The epoxides (81) themselves have been synthesized by treatment of 4,7-dihydro-1,3-dioxepins (77) withp-nitro- <75BSF1763> or w-chloroperbenzoic acid <75TL2643> or HOCI/H2O2 <8IEUP33426). Alternatively, hexafluoroacetone/hydrogen peroxide in disodium hydrogen phosphate buffered... 

Oxirans.— Epoxides are readily available from the catalytic oxidation of alkenes with 2-hydroperoxyhexafluoropropan-2-ol (HPHI) (1), which itself is easily prepared from hexafluoroacetone hydrate (2) and hydrogen peroxide (Scheme 1). HPHI is claimed to have similarities to the natural flavin hydroperoxides which are implicated in epoxidations and hydroxylations by external flavoprotein mono-oxygenases. Yields are typically in the range 77—92%. 

Similarly, the adduct of hydrogen peroxide with hexafluoroacetone is an active epoxidizing reagent. ... 

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