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Ligand-Enabled ?-C(sp3 )-H Olefination of Free Carboxylic Acids.

ABSTRACT: We report the ligand-enabled C-H activation/olefination of free carboxylic acids in the ?-position. Through an intramolecular Michael addition, ?-lactones are obtained as products. Two distinct ligand classes are identified that enable the challenging palladium-catalyzed activation of free carboxylic acids in the ?-position. The developed protocol features a wide range of acid substrates and olefin reaction partners and is shown to be applicable on a preparatively useful scale. Insights into the underlying reaction mechanism obtained through kinetic studies are reported.

SUBMITTER: Ghosh KK

PROVIDER: S-EPMC7496353 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Ligand-Enabled γ-C(sp3 )-H Olefination of Free Carboxylic Acids.

Ghosh Kiron Kumar KK Uttry Alexander A Mondal Arup A Ghiringhelli Francesca F Wedi Philipp P van Gemmeren Manuel M

Angewandte Chemie (International ed. in English) 20200518 31

We report the ligand-enabled C-H activation/olefination of free carboxylic acids in the γ-position. Through an intramolecular Michael addition, δ-lactones are obtained as products. Two distinct ligand classes are identified that enable the challenging palladium-catalyzed activation of free carboxylic acids in the γ-position. The developed protocol features a wide range of acid substrates and olefin reaction partners and is shown to be applicable on a preparatively useful scale. Insights into the ...[more]

PMID: 32250014

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