NHC‐Catalyzed Desymmetrization of N‐Aryl Maleimides Leading to the Atroposelective Synthesis of N‐Aryl Succinimides

Although the construction of axially chiral C−C bonds leading to the atroposelective synthesis of biaryls and allied compounds are well‐known, the related synthesis of compounds bearing axially chiral C−N bonds are relatively rare. Described herein is the N‐heterocyclic carbene‐catalyzed atroposelective synthesis of N‐aryl succinimides having an axially chiral C−N bond via the desymmetrization of N‐aryl maleimides. The NHC involved intermolecular Stetter‐aldol cascade of dialdehydes with prochiral N‐aryl maleimides followed by oxidation afforded N‐aryl succinimides in good yields and ee values. Preliminary studies on rotation barrier for the C−N bond, the temperature dependence, and detailed DFT studies on mechanism are also provided. NHC‐catalyzed atroposelective synthesis of N‐aryl succinimides having an axially chiral C−N bond via the desymmetrization of N‐aryl maleimides is presented. The reaction proceeds via the Stetter‐aldol cascade of dialdehydes with prochiral N‐aryl maleimides followed by oxidation. Preliminary studies on the rotation barrier for the C−N bond and detailed DFT studies on the mechanism are also provided.