Enantioselective Catalytic Methods for the Elaboration of Chiral Tetrahydro-β-carbolines and Related Scaffolds

Abstract

Tetrahydro-β-carbolines are important synthetic intermediates in the total synthesis of natural products and of compounds exhibiting strong bioactivities. Over the last decades, catalytic methods using chiral catalysts have been described for their synthesis. This review covers catalytic and enantioselective methods to access chiral tetrahydro-β-carbolines and their applications in the elaboration of complex chiral molecules.1 Introduction2 Asymmetric Reduction of Dihydro-β-carbolines2.1 Asymmetric Transfer Hydrogenation Reactions2.2 Asymmetric Hydrogenation Reactions2.3 Biocatalyzed Reduction of Dihydro-β-carbolines3 Organocatalyzed Pictet–Spengler Reactions3.1 Chiral Thiourea-Catalyzed Reactions3.2 Chiral Phosphoric Acid Catalyzed Reactions4 Pictet–Spengler Reactions of In Situ Generated Cyclic Iminiums5 Organocatalyzed Functionalization of Dihydro-β-carboliniums6 Organocatalyzed Alkylation of Tetrahydro-β-carbolines7 Biocatalyzed Dynamic Kinetic Resolution of Tetrahydro-β-carbolines8 Conclusion and Perspectives