Recent Advances on Transition-Metal-Catalyzed Asymmetric C–H Arylation Reactions

Abstract Transition-metal-catalyzed asymmetric C–H functionalization has become a powerful strategy to synthesize complex chiral molecules. Recently, catalytic enantioselective C–H arylation has attracted great interest from organic chemists to construct aryl-substituted chiral compounds. In this short review, we highlight recent advances in asymmetric C–H arylation from 2019 to late 2021, including enantioselective C(sp2)–H arylation to construct axial or planar chiral compounds, and enantioselective C(sp3)–H arylation to introduce central chirality via desymmetrization of the methyl group or methylene C–H activation. These processes proceed with palladium, rhodium, iridium, nickel, or copper catalysts, and utilize aryl halides, boron, or diazo derivatives as arylation reagents. 1 Introduction 2 Transition-Metal-Catalyzed Asymmetric C(sp2)–H Arylation 2.1 Chelation-Assisted Asymmetric C(sp2)–H Arylation for the Construction of Atropisomer 2.2 Chelation-Assisted Asymmetric C(sp2)–H Arylation for the Construction of Planar Chiral Compounds 2.3 Chelation-Assisted Asymmetric C(sp2)–H Arylation and Axial-to-Central Chirality Transfer for the Construction of Spirocycles 2.4 Other Asymmetric C(sp2)–H Arylation Reactions 3 Transition-Metal-Catalyzed Asymmetric C(sp3)–H Arylation 3.1 Chelation-Assisted Enantioselective C(sp3)–H Arylation through Desymmetrization 3.2 Chelation-Assisted Enantioselective Methylene C(sp3)–H Aryl­ation 3.3 Other Asymmetric C(sp3)–H Arylations 4 Conclusion and Outlook