Chiral Transient Directing Groups in Transition-Metal-Catalyzed Enantioselective C-H Bond Functionalization

Transition-metal-catalyzed C-H bond functionalization has known a rapid evolution in the last years, offering modern strategies for reaching high molecular complexity in a step- and atom-economical way. Despite the indisputable advances, selectivity issues still remain, given the ubiquity of C-H bonds on molecules; thus, several approaches have been developed to tackle this challenge. Among them, the use of a transient directing group has emerged as an effective tool, circumventing the need for extra synthetic steps to install and then cleave a directing group on the molecule. More recently, this strategy has been successfully applied to the even more challenging transition-metal-catalyzed enantioselective C-H bond functionalization. This review will highlight and discuss the main advances made in the use of a chiral transient directing group for the enantioselective functionalization of C(sp(2))-H and C(sp(3))-H bonds by transition-metal catalysis.