F-Butyl hydroperoxide-Vanadyl acetylacetonate

Oxidation of j8-dicarbonyl compounds by f-butyl hydroperoxide in the presence of vanadyl acetylacetonate [VO(acac)2] in benzene results in decomposition of the carbon skeleton, via intermediate trioxo derivatives." ... 

Very interesting results were obtained during studies on the epoxidation of /f-hydroxy enones 8. Attempts at selective epoxidation under typical basic conditions failed and 2 3 mixtures of syn- and anf/-epoxides 9 were obtained. Surprisingly, epoxidation using Sharpless conditions, titanium tetraisopropoxide/tm-butyl hydroperoxide or vanadyl acetylacetonate/rm-butyl hydroperoxide, which are normally unreactive towards simple enones, proceeded smoothly, yielding exclusively syn-epoxy alcohols syn-9. No epoxidation took place for the corresponding nitrile or when the hydroxy function was blocked as a silyl ether32. 

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