Chemistry of Oxaziridines. 4. Asymmetric Epoxidation of Unfunctionalized Alkenes Using Chiral 2-Sulfonyloxaziridines: Evidence for a Planar Transition State Geometry

Article abstract of DOI:10.1021/ja00348a029

Diastereomeric 2-sulfonyloxaziridines (-)-(S,S)-1 and (+)-(R,R)-2 epoxidize unfunctionalized olefins 3a-g, affording epoxides 4a-g with better enantioselectivity than do chiral peracids or hydroperoxides.The configuration of the oxaziridine three-membered ring controls the stereochemistry of the product.The mechanism of chiral recognition is largely determined by steric factors where the orientations of the oxaziridine three-membered ring and the alkene are planar in the transition state.