Enantioselective Organocatalytic Diels-Alder Reactions

Enantioselective organocatalytic asymmetric Diels-Alder reactions provide a facile and efficient route to optically active functionalized cyclohexenes, which can be further transformed into a variety of important organic compounds. A variety of small organic molecules such as prolines, imidazolidinones, chiral Bronsted acids, guanidines, carbenes and Cinchona alkaloids can be used as different catalyst systems to induce enantioselectivity in the reaction. This review provides an overview of the history of the asymmetric organocatalyzed Diels-Alder reaction. 1 Introduction 2 Chiral-Base-Catalyzed Diels-Alder Reactions 2.1 Chiral Secondary Amines 2.2 Chiral Primary Amines 2.3 Cinchona Alkaloids 2.4 Heterocyclic Carbenes 2.6 Chiral Guanidines 3 Hydrogen-Bond-Catalyzed Diels-Alder Reactions 4 Concluding Remarks