Asymmetric Diels-Alder reactions of 2-pyrones with a bifunctional organic catalyst

The reactions of 2-pyrones with electron-deficient dienophiles constitute a synthetically useful class of Diels-Alder reaction. By exploring cinchona alkaloid-derived organic molecules as acid-base bifunctional catalysts, we successfully developed the first highly enantioselective and diastereoselective catalytic Diels-Alder reaction with 2-pyrones. Furthermore, we demonstrated the possibility of using such catalysts to control the endo/exo selectivity in a Diels-Alder reaction.