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Catalytic Ring-Opening of Cyclic Alcohols Enabled by PCET Activation of Strong O-H Bonds.

ABSTRACT: We report a new photocatalytic protocol for the redox-neutral isomerization of cyclic alcohols to linear ketones via C-C bond scission. Mechanistic studies demonstrate that key alkoxy radical intermediates in this reaction are generated via the direct homolytic activation of alcohol O-H bonds in an unusual intramolecular PCET process, wherein the electron travels to a proximal radical cation in concert with proton transfer to a weak Brønsted base. Effective bond strength considerations are shown to accurately forecast the feasibility of alkoxy radical generation with a given oxidant/base pair.

SUBMITTER: Yayla HG

PROVIDER: S-EPMC5110324 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Catalytic Ring-Opening of Cyclic Alcohols Enabled by PCET Activation of Strong O-H Bonds.

Yayla Hatice G HG Wang Huaiju H Tarantino Kyle T KT Orbe Hudson S HS Knowles Robert R RR

Journal of the American Chemical Society 20160818 34

We report a new photocatalytic protocol for the redox-neutral isomerization of cyclic alcohols to linear ketones via C-C bond scission. Mechanistic studies demonstrate that key alkoxy radical intermediates in this reaction are generated via the direct homolytic activation of alcohol O-H bonds in an unusual intramolecular PCET process, wherein the electron travels to a proximal radical cation in concert with proton transfer to a weak Brønsted base. Effective bond strength considerations are shown ...[more]

PMID: 27515494

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