can be prepared by the catalytic enantioselective cross-aldol reaction of acetone with trihalomethyl ketones by usingN-(8-quinolinesulfonyl)prolinamide as an organocatalyst. The MO calculations elucidate that the hydrogen bonding between the sulfonimide proton and the 8-quinolyl nitrogen atom plays an important role in exerting the enantioselectivity of the reaction.