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Remote Radical Desaturation of Unactivated C-H Bonds in Amides.

ABSTRACT: Desaturation of inert aliphatic C-H bonds in alkanes to form the corresponding alkenes is challenging. In this communication, a new and practical strategy for remote site-selective desaturation of amides via radical chemistry is reported. The readily installed N-allylsulfonylamide moiety serves as an N radical precursor. Intramolecular 1,5-hydrogen atom transfer from an inert C-H bond to the N-radical generates a translocated C-radical which is subsequently oxidized and deprotonated to give the corresponding alkene. The commercially available methanesulfonyl chloride is used as reagent and a Cu/Ag-couple as oxidant. The remote desaturation is realized on different types of unactivated sp³ -C-H bonds. The potential synthetic utility of this method is further demonstrated by the dehydrogenation of natural product derivatives and drugs.

SUBMITTER: Xia Y

PROVIDER: S-EPMC9292639 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Remote Radical Desaturation of Unactivated C-H Bonds in Amides.

Xia Yong Y Jana Kalipada K Studer Armido A

Chemistry (Weinheim an der Bergstrasse, Germany) 20211008 67

Desaturation of inert aliphatic C-H bonds in alkanes to form the corresponding alkenes is challenging. In this communication, a new and practical strategy for remote site-selective desaturation of amides via radical chemistry is reported. The readily installed N-allylsulfonylamide moiety serves as an N radical precursor. Intramolecular 1,5-hydrogen atom transfer from an inert C-H bond to the N-radical generates a translocated C-radical which is subsequently oxidized and deprotonated to give the ...[more]

PMID: 34590351

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