Lewis Acid Catalyzed Dynamic Kinetic Asymmetric Transformation of Racemic N‑Sulfonylaziridines

The first Lewis acid catalyzed stereoconvergent transformation of racemic 2-(hetero)­aryl-N-sulfonylaziridines via C–N bond cleavage with nucleophiles is presented. This includes the [3 + 2] annulations with (hetero)­aromatic aldehydes and 1,3-disubstituted indoles, asymmetric Friedel–Crafts type reaction with electron-rich (hetero)­arenes, and asymmetric aminolysis with amines, providing facile access to chiral 1,3-isoxazolidines, pyrroloindolines, 2-(hetero)­arylphenethylamines, and vicinal diamines. This method features a simple and cheaply available complex of Cu­(I)–chiral BINAP catalyst, excellent yield and high diastereo- and enantioselectivities, and mild reaction conditions. A mechanism involving type I dynamic kinetic asymmetric transformations (DyKATs) of the racemic aziridines is proposed based on the results of control experiments.