Desymmetrization and Kinetic Resolution of Endoperoxides Using a Bifunctional Organocatalyst.

Bifunctional thiourea/amine organocatalysts have been used for the desymmetrization of meso -endoperoxides using the Kornblum-DeLaMare reaction, giving 4-hydroxyketones in 78-98% yields with ≤98:2 enantioselectivity. The influence of the catalyst structure, solvent, and temperature was examined. The most promising catalyst was applied to the kinetic resolution of racemic endoperoxides to give enantioenriched materials (≤99:1 er).