Asymmetric Epoxidation of Electron-Deficient α,β-Enones

Abstract

Zhao and co-workers report an asymmetric epoxidation of electron-deficient α,β-unsaturated ketones using prolinol 1 as catalyst. Different β,γ-unsaturated α-keto esters, α,β-unsaturated trichloromethyl and α,β-trifluoromethyl ketones were investigated in this reaction. Moreover, the synthetic applicability of the corresponding products is shown in several transformations. Remarkable is the three-step synthesis of (-)-(5R,6S)-norbalasubramide and (-)-(5R,6S)-­balasubramide.