Recent Advances of Asymmetric Catalysis in Flow for Drug Discovery

Abstract

Enantioselective continuous-flow catalysis enables highly efficient synthesis of optically active compounds. The early examples of this field were mainly limited to homogeneous catalysis, and enantioselective heterogeneous flow catalysis remained challenging in terms of activity, selectivity, and lifetime. However, there have been continuous developments in recent years toward highly active and selective chiral heterogeneous catalysts. Besides, technology development enabled in-line workup and analysis of flow reactions to make the process more efficient. This review summarizes the recent achievements of enantioselective flow catalysis mainly focusing on chiral heterogeneous catalysts. Successful examples in recent 5 years are categorized and discussed based on the types of reactions, including transition metal catalysis, organocatalysis, and enzymatic reactions. Multistep-flow synthesis of optically active compounds using enantioselective catalysis is also discussed in the last chapter.