The catalytic activity of the prolinamide-type catalysts may be improved by introducing additional prolinamide moiety into the catalyst, while the enantioselectivity can still be maintained or further improved. AC 2-symmetric bisprolinamide with two prolinamide moieties has been found to be an excellent catalyst for direct aldol reaction with more than doubled reactivity and better asymmetric induction than its monoprolinamide counterpart.
