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Mild deoxygenation of aromatic ketones and aldehydes over Pd/C using polymethylhydrosiloxane as the reducing agent.

ABSTRACT: Herein, a practical and mild method for the deoxygenation of a wide range of benzylic aldehydes and ketones is described, which utilizes heterogeneous Pd/C as the catalyst together with the green hydride source, polymethylhydrosiloxane. The developed catalytic protocol is scalable and robust, as exemplified by the deoxygenation of ethyl vanillin, which was performed on a 30?mmol scale in an open-to-air setup using only 0.085?mol?% Pd/C catalyst to furnish the corresponding deoxygenated product in 93?% yield within 3?hours at room temperature. Furthermore, the Pd/C catalyst was shown to be recyclable up to 6 times without any observable decrease in efficiency and it exhibited low metal leaching under the reaction conditions.

SUBMITTER: Volkov A

PROVIDER: S-EPMC4471587 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Mild deoxygenation of aromatic ketones and aldehydes over Pd/C using polymethylhydrosiloxane as the reducing agent.

Volkov Alexey A Gustafson Karl P J KP Tai Cheuk-Wai CW Verho Oscar O Bäckvall Jan-E JE Adolfsson Hans H

Angewandte Chemie (International ed. in English) 20150226 17

Herein, a practical and mild method for the deoxygenation of a wide range of benzylic aldehydes and ketones is described, which utilizes heterogeneous Pd/C as the catalyst together with the green hydride source, polymethylhydrosiloxane. The developed catalytic protocol is scalable and robust, as exemplified by the deoxygenation of ethyl vanillin, which was performed on a 30 mmol scale in an open-to-air setup using only 0.085 mol % Pd/C catalyst to furnish the corresponding deoxygenated product i ...[more]

PMID: 25728614

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