Practical and Site-Selective Photoinitiated C(sp3)–H Bond Chlorination of Ketones, (E)-1,3-Enones, and Alkylbenzenes by Chloramine-T and N-Chlorosuccinimide
Issued Date
2025-01-01
Resource Type
ISSN
1001604X
eISSN
16147065
Scopus ID
2-s2.0-105022623678
Journal Title
Chinese Journal of Chemistry
Rights Holder(s)
SCOPUS
Bibliographic Citation
Chinese Journal of Chemistry (2025)
Suggested Citation
Zhang Y., Diaz J., Senapati S., La-ongthong K., Ung Y.C., Kuhakarn C., Jin J., Koenigs R.M., Chan P.W.H. Practical and Site-Selective Photoinitiated C(sp3)–H Bond Chlorination of Ketones, (E)-1,3-Enones, and Alkylbenzenes by Chloramine-T and N-Chlorosuccinimide. Chinese Journal of Chemistry (2025). doi:10.1002/cjoc.70367 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/113279
Title
Practical and Site-Selective Photoinitiated C(sp3)–H Bond Chlorination of Ketones, (E)-1,3-Enones, and Alkylbenzenes by Chloramine-T and N-Chlorosuccinimide
Author's Affiliation
Corresponding Author(s)
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Abstract
A practical photoinitiated synthetic method for the site-selective γ - and α-chlorination of C(sp<sup>3</sup>)–H bonds of ketones, (E)-1,3-enones, and alkylbenzenes by chloramine-T (CAT) and N-chlorosuccinimide (NCS) under blue LED (λ<inf>max</inf> = 456 nm) light irradiation is reported. Mechanistic studies suggest the reaction to proceed via a radical pathway where the chlorination reagent dichloramine-T (DCT) is generated in situ from the reaction of CAT with NCS. Its premised controlled formation along with that of the carbon-centered radical species derived from the substrate is thought to contribute to product site-selectivity. The developed protocol operates under mild reaction conditions at room temperature and demonstrates excellent functional group tolerance as exemplified by the site-selective γ-C(sp<sup>3</sup>)–H bond chlorination of carboxylic esters and amides, and late-stage functionalization of several bioactive natural products and drug molecules. The study also highlights the potential of CAT for the first time as a versatile and controllable chlorine radical atom source for site-selective halogenation reactions, expanding its synthetic utility beyond traditional applications.