Access to C─N and N─N Axially Chiral Pyridinones via NHC‐Catalyzed Dynamic Kinetic Resolution of Rotationally Restricted Cyclic Imides

Atropisomers bearing C─N or N─N axes are an important class of chiral molecules, yet stereoconvergent strategies for accessing these compounds using organocatalytic techniques remain limited. Herein, we report the N-heterocyclic carbene (NHC)-catalyzed dynamic kinetic resolution (DKR) of rotationally restricted cyclic imides via (3 + 3) annulation with enals under oxidative conditions for the synthesis of C─N or N─N axially chiral pyridinones. Mechanistic experiments shed light on keto-enol tautomerism in cyclic imides, which serves as the operative mode of enantiomer interconversion. This transformation furnishes C─N/N─N axially chiral frameworks bearing a remote stereogenic center in high yields with excellent enantioselectivity (up to 99:1 er) and good diastereocontrol. Rotation barrier studies confirm the high configurational stability of the products. Reactions conducted using pre-formed carbenes provide information on DKR operating in the present case over the competing desymmetrization pathway.