The optimized conditions reported for the proline-catalyzed aldol reaction between ketone donors and aldehyde acceptors typically require the use of 30-40 mol% of proline and an large excess of ketone in anhydrous DMSO (or DMF). [1] With more expensive ketones as donors, this is neither economical nor practical because it complicates the purification of the product, particularly if a substantial excess of the ketone is used and the ketone is not volatile. This is especially ...
