Preparation of a Fluorous Chiral BINOL Derivative and Application to an Asymmetric Protonation Reaction

Fluorous Chiral Proton Source (R,S)-FDHPEB resulted in a higher enantioselectivity (95% ee) than that of the original nonfluorous (R,S)-DHPEB (87% ee) in an enantioselective protonation of a samarium enolate. (R,S)-FDHPEB was easily recovered by a simple filtration through a fluorous reverse phase silica gel and was recyclable.