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Direct C(sp3)-H Cross Coupling Enabled by Catalytic Generation of Chlorine Radicals.

ABSTRACT: Here we report the development of a C(sp3)-H cross-coupling platform enabled by the catalytic generation of chlorine radicals by nickel and photoredox catalysis. Aryl chlorides serve as both cross-coupling partners and the chlorine radical source for the ?-oxy C(sp3)-H arylation of cyclic and acyclic ethers. Mechanistic studies suggest that photolysis of a Ni(III) aryl chloride intermediate, generated by photoredox-mediated single-electron oxidation, leads to elimination of a chlorine radical in what amounts to the sequential capture of two photons. Arylations of a benzylic C(sp3)-H bond of toluene and a completely unactivated C(sp3)-H bond of cyclohexane demonstrate the broad implications of this manifold for accomplishing numerous C(sp3)-H bond functionalizations under exceptionally mild conditions.

SUBMITTER: Shields BJ

PROVIDER: S-EPMC5215658 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Direct C(sp3)-H Cross Coupling Enabled by Catalytic Generation of Chlorine Radicals.

Shields Benjamin J BJ Doyle Abigail G AG

Journal of the American Chemical Society 20160921 39

Here we report the development of a C(sp3)-H cross-coupling platform enabled by the catalytic generation of chlorine radicals by nickel and photoredox catalysis. Aryl chlorides serve as both cross-coupling partners and the chlorine radical source for the α-oxy C(sp3)-H arylation of cyclic and acyclic ethers. Mechanistic studies suggest that photolysis of a Ni(III) aryl chloride intermediate, generated by photoredox-mediated single-electron oxidation, leads to elimination of ...[more]

PMID: 27653738

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