Catalytic Metalloradical System for Radical 1,6-C(sp 3 )–H Amination with Concurrent Control of Site-, Chemo-, and Enantio-selectivity
Year: 2025
Type: article
Abstract: -symmetric chiral amidoporphyrin ligand, the Co(II)-based metalloradical system effectively catalyzes chemoselective amination of propargylic, allylic, and benzylic C-H bonds at 1,6- over 1,5-positions of alkoxysulfonyl azides, achieving high enantioselectivity. This Co(II)-catalyzed process, which operates at room temperature, is applicable to a broad range of alkoxysulfonyl azides with a high tolerance of functional groups, enabling the efficient construction of six-membered sulfamidates in high yields with excellent enantioselectivities. Comprehensive experimental investigations, complemented by computational studies, elucidate the stepwise radical mechanism underlying this transformation. The resulting six-membered cyclic sulfamidates from the enantioselective radical process can undergo stereospecific ring-opening reactions with various nucleophiles, affording γ-functionalized α-chiral amines in high yields while retaining the original enantiopurity. Since alkoxysulfonyl azides are readily synthesized from widely available alcohols through a nucleophilic azide transfer, this union of the radical and ionic processes constitutes a versatile 1,3-difunctionalization of alcohols.
DOI: 10.1021/jacs.5c03259
Authors: Yiling Zhu, Wan-Chen Cindy Lee, X. Peter Zhang
Institution: Boston College
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4409662818