Forging C-heteroatom bonds by transition-metal-catalyzed enantioselective C-H functionalization

Direct C-H functionalization has recently emerged as one of the most efficient strategies to access structurally complex molecules from readily accessible feedstocks in an atom- and step-economic manner. In particular, enantioselective C-H activation has garnered increasing attention by enabling chemists to efficiently assemble valuable chiral compounds by asymmetrically manipulating C-H bonds into useful functionalities. Apart from the extensively studied C-C bond formation, very few endeavors have been focused on the C-X formation analogs. Motivated by the utility of the latter approach in constructing academically and industrially important heteroatom-containing chiral compounds, we provide herein an overview on C-X forming asymmetric C-H activation reactions proceeding through C-H metalation. The advancements are organized according to the employed catalytic systems, which include Pd(II) catalysis, group-9 (CpM)-M-x(III) catalysis, monovalent group-9 metal catalysis, and multi-boryl/silyl Ir(III) catalysis, with emphasis on the design philosophy, mechanism, and mode of enantiocontrol.