摘要:
Asymmetric epoxidation of a variety of enones 3, 6, 8, 10, 12, 14, 16, 18, 21, 22, 26, 28-30 and 36 gives the corresponding oxiranes in good to excellent yield and optical purity, The oxidation medium consists of basic peroxide or sodium perborate or sodium percarbonate or tert-butylhydroperoxide and the preferred catalyst is polyleucine, conveniently prepared from the N-carboxyanhydride using 1,3-diaminopropane.