Asymmetric epoxidation catalyzed by N-aryl-substituted oxazolidinone-containing ketones: further evidence for electronic effects.

[reaction: see text] Ketones containing N-aryl-substituted oxazolidinones have been prepared and investigated for the epoxidation of cis-beta-methylstyrene, styrene, and 1-phenylcyclohexene. The attractive interaction between the phenyl group of the olefin and the oxazolidinone of the catalyst is enhanced by introducing an electron-withdrawing group onto the N-phenyl group of the catalyst. The information obtained gives a better understanding of the ketone-catalyzed epoxidation. In addition, the easy preparation of some of the ketones makes them good candidates for practical use.