2.3 Dual Catalysis with Two Organocatalysts

The field of asymmetric organocatalysis has attracted the attention of chemists due to the environmentally benign conditions, particularly for the synthesis of chiral molecules, bioactive compounds, natural products, and drugs. Besides the conventional approaches using a single organocatalyst in asymmetric reactions, dual catalysis with two organocatalysts has emerged as an important strategy for resolving existing challenging problems, including the synthesis of complex molecules, improvement of enantioselectivities, and the development of new catalytic mechanisms. In this review, selected recent examples of the combination of two organocatalysts are covered in detail. Moreover, future perspectives are also described.