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Direct Use of Carboxylic Acids in the Photocatalytic Hydroacylation of Styrenes To Generate Dialkyl Ketones.

ABSTRACT: A general protocol for the hydroacylation of styrenes from aliphatic carboxylic acids is reported. These reactions proceed via ?-scission of a phosphoranyl radical that is accessed by photoredox catalysis, followed by addition of the resulting acyl radical to the styrenyl olefin. We show that phosphine tunability is critical for efficient intermolecular coupling due to competitive quenching of the photocatalyst by the olefin. Primary, secondary, and structurally rigid tertiary carboxylic acids all generate valuable unsymmetrical dialkyl ketones.

SUBMITTER: Martinez Alvarado JI

PROVIDER: S-EPMC6927213 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Direct Use of Carboxylic Acids in the Photocatalytic Hydroacylation of Styrenes To Generate Dialkyl Ketones.

Martinez Alvarado Jesus I JI Ertel Alyssa B AB Stegner Andrea A Stache Erin E EE Doyle Abigail G AG

Organic letters 20191121 24

A general protocol for the hydroacylation of styrenes from aliphatic carboxylic acids is reported. These reactions proceed via β-scission of a phosphoranyl radical that is accessed by photoredox catalysis, followed by addition of the resulting acyl radical to the styrenyl olefin. We show that phosphine tunability is critical for efficient intermolecular coupling due to competitive quenching of the photocatalyst by the olefin. Primary, secondary, and structurally rigid tertiary carboxylic acids a ...[more]

PMID: 31750667

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