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Photocatalytic carbanion generation from C-H bonds - reductant free Barbier/Grignard-type reactions.

ABSTRACT: We report a redox-neutral method for the generation of carbanions from benzylic C-H bonds in a photocatalytic Grignard-type reaction. The combination of photo- and hydrogen atom transfer (HAT) catalysis enables the abstraction of a benzylic hydrogen atom, generating a radical intermediate. This radical is reduced in situ by the organic photocatalyst to a carbanion, which is able to react with electrophiles such as aldehydes or ketones, yielding homobenzylic secondary and tertiary alcohols.

SUBMITTER: Berger AL

PROVIDER: S-EPMC8133029 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Photocatalytic carbanion generation from C-H bonds - reductant free Barbier/Grignard-type reactions.

Berger Anna Lucia AL Donabauer Karsten K König Burkhard B

Chemical science 20191112 48

We report a redox-neutral method for the generation of carbanions from benzylic C-H bonds in a photocatalytic Grignard-type reaction. The combination of photo- and hydrogen atom transfer (HAT) catalysis enables the abstraction of a benzylic hydrogen atom, generating a radical intermediate. This radical is reduced <i>in situ</i> by the organic photocatalyst to a carbanion, which is able to react with electrophiles such as aldehydes or ketones, yielding homobenzylic secondary and tertiary alcohols ...[more]

PMID: 34040714

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