ASYMMETRIC DIELS-ALDER REACTION OF CYCLOPENTADIENE WITH METHACROLEIN USING POLYMER-SUPPORTED CHIRAL CATALYSTS

Polymer-supported chiral Lewis acids were prepared from bromoboranes a nd crosslinked polymers having chiral amino alcohol or diol moieties. These polymers were used as chiral catalysts for Diels-Alder reactions of cyclopentadiene with methacrolein to give optically active cycload duct in high chemical yield with high exo selectivity. Optical yield u p to 54% ee was obtained by the use of polymeric chiral catalyst deriv ed from (S)-proline. The potential of this type of approach in asymmet ric synthesis is discussed.