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Updated: Dec 1, 2025

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Photoinduced Site-Selective C(sp3)-H Chlorination of Aliphatic Amides
Yanshuo Zhu1, Jingcheng Shi1, Wei Yu1
1State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China.
Abstract:
Herein, we report a new photochemical method for C(sp3)-H chlorination of amides which employs tert-butyl hypochlorite as the chlorinating agent and a household compact fluorescent lamp as the light source. The reaction proceeds via N-heterocyclic carbene SIPr·HCl-promoted N-H chlorination and subsequent photoinduced Hofmann-Löffler-Freytag chlorine atom transfer. The latter process is facilitated by (diacetoxyiodo)benzene. This protocol exhibits a broad scope and is suitable for site-selective chlorination of methyl hydrogen as well as methylene and methine hydrogen.
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