Enantioselective C(sp 3 )‒H bond activation by chiral transition metal catalysts

Organic molecules are rich in carbon-hydrogen bonds; consequently, the transformation of C-H bonds to new functionalities (such as C-C, C-N, and C-O bonds) has garnered much attention by the synthetic chemistry community. The utility of C-H activation in organic synthesis, however, cannot be fully realized until chemists achieve stereocontrol in the modification of C-H bonds. This Review highlights recent efforts to enantioselectively functionalize C(sp3)-H bonds via transition metal catalysis, with an emphasis on key principles for both the development of chiral ligand scaffolds that can accelerate metalation of C(sp3)-H bonds and stereomodels for asymmetric metalation of prochiral C-H bonds by these catalysts.