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

• Published in: Organic letters Vol. 23; no. 20; pp. 7933 - 7937
• Main Authors: Zhu, Guo-Sheng, Yang, Pei-Jun, Ma, Chen-Xue, Yang, Gaosheng, Chai, Zhuo
• Format: Journal Article
• Language: English
• Published: American Chemical Society 15-10-2021
• ISSN: 1523-7060; 1523-7052
• DOI: 10.1021/acs.orglett.1c02931

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.