Electrophilic Epoxidation of α,β-Unsaturated Oximes with Dioxiranes and Ring Opening of the Epoxides

α,β-Unsaturated oximes underwent electrophilic epoxidation with in-situ-generated dimethyldioxirane to give the corresponding epoxides in good yields. This reaction is an example of “carbonyl umpolung” by transformation α,β-unsaturated ketones their oximes. Nucleophilic ring-opening reactions afforded α-substituted products. Shi asymmetric proceeded moderate enantioselectivity.