Catalytic Asymmetric [3 + 2] Annulation of Hantzsch Esters with Racemic N‑Sulfonylaziridines

Hantzsch esters (HEs) served as two-carbon partners in a copper­(I)-catalyzed enantioselective [3 + 2] annulation with racemic 2-(hetero)­aryl-N-sulfonyl aziridines via kinetic resolution to provide pyrrolo­[2,3-b]­tetrahydropyridines containing multiple contiguous stereogenic centers including all-carbon quaternary centers in excellent yields and enantiopurities and moderate-to-excellent diastereoselectivities. Mainly dependent upon the structures of the aziridines, a competitive hydrogenolysis process with HEs as the hydrogen source was also observed in some cases.