Stereoselective vanadium-catalysed epoxidation of α,β-unsaturated ketones possessing a neighbouring hydroxy group
Abstract
α,β-Unsaturated ketones possessing a hydroxy group two or three bonds away from the β-carbon can be stereoselectively epoxidized with t-butyl hydroperoxide in the presence of bisacetylacetonato-oxovanadium as catalyst. The reaction was applied to steroidal substrates in which the double bond is di- or tri-substituted and the hydroxy group is secondary or tertiary.