Enantioselective Diels-Alder reaction of simple α,β-unsaturated ketones with a cinchona alkaloid catalyst

Article abstract of DOI:10.1021/ja078251w

The simple α,β-unsaturated ketones and 2-pyrones are readily available and synthetically important dienophiles and dienes, respectively, for Diels-Alder reactions. However, both prove to be challenging substrates for catalytic asymmetric Diels-Alder reactions. By exploring a new catalysis strategy featuring cooperative catalysis with readily available cinchona catalysts, an unprecedented asymmetric Diels-Alder reaction of simple α,β-unsaturated ketones with 2-pyrones has been successfully developed. With broad scopes for both reactants, the reaction provides a direct and versatile asymmetric access to a wide range of structurally novel bicyclic chiral building blocks amenable for further synthetic elaborations. Copyright