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Birch-Type Photoreduction of Arenes and Heteroarenes by Sensitized Electron Transfer.

ABSTRACT: The direct reduction of arenes and heteroarenes by visible-light irradiation remains challenging, as the energy of a single photon is not sufficient for breaking aromatic stabilization. Shown herein is that the energy accumulation of two visible-light photons allows the dearomatization of arenes and heteroarenes. Mechanistic investigations confirm that the combination of energy-transfer and electron-transfer processes generates an arene radical anion, which is subsequently trapped by hydrogen-atom transfer and finally protonated to form the dearomatized product. The photoreduction converts planar aromatic feedstock compounds into molecular skeletons that are of use in organic synthesis.

SUBMITTER: Chatterjee A

PROVIDER: S-EPMC6790943 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Birch-Type Photoreduction of Arenes and Heteroarenes by Sensitized Electron Transfer.

Chatterjee Anamitra A König Burkhard B

Angewandte Chemie (International ed. in English) 20190827 40

The direct reduction of arenes and heteroarenes by visible-light irradiation remains challenging, as the energy of a single photon is not sufficient for breaking aromatic stabilization. Shown herein is that the energy accumulation of two visible-light photons allows the dearomatization of arenes and heteroarenes. Mechanistic investigations confirm that the combination of energy-transfer and electron-transfer processes generates an arene radical anion, which is subsequently trapped by hydrogen-at ...[more]

PMID: 31379035

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