Electronic probing of ketone catalysts for asymmetric epoxidation. Search for more robust catalysts.

[structure: see text]. Ketones with a fused oxazolidinone were synthesized and investigated to determine the electronic effect of the substituents at alpha-positions of ketone catalysts on the Baeyer-Villiger oxidation and catalytic properties for asymmetric epoxidation. These new ketones give high yields and ee's with only 1-5 mol % catalyst. The current studies further show that the electronic effect is very important for the ketone-catalyzed epoxidation.