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Tsuji-Wacker-Type Oxidation beyond Methyl Ketones: Reacting Unprotected Carbohydrate-Based Terminal Olefins through the "Uemura System" to Hemiketals and ?,?-Unsaturated Diketones.

ABSTRACT: Aerobic Pd(AcO)2/pyridine-catalyzed oxidation of unprotected carbohydrate-based terminal alkenes was studied. In accordance with previous reports, the initial reaction step gave methyl ketones. However, our substrates partially gave subsequent ?,?-water elimination and alcohol oxidation to ?,?-unsaturated 2,5-diketones. Upon increasing the pressure of O2, the reaction was shifted toward formation of ?,?-epoxy-2-ketones. The reactions were stereoselective and gave up to quantitative conversions. However, isolated yields were substantially lower because of the complexity of the product mixtures.

SUBMITTER: Runeberg PA

PROVIDER: S-EPMC7076729 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Tsuji-Wacker-Type Oxidation beyond Methyl Ketones: Reacting Unprotected Carbohydrate-Based Terminal Olefins through the "Uemura System" to Hemiketals and α,β-Unsaturated Diketones.

Runeberg Patrik A PA Eklund Patrik C PC

Organic letters 20190926 20

Aerobic Pd(AcO)<sub>2</sub>/pyridine-catalyzed oxidation of unprotected carbohydrate-based terminal alkenes was studied. In accordance with previous reports, the initial reaction step gave methyl ketones. However, our substrates partially gave subsequent α,β-water elimination and alcohol oxidation to α,β-unsaturated 2,5-diketones. Upon increasing the pressure of O<sub>2</sub>, the reaction was shifted toward formation of α,β-epoxy-2-ketones. The reactions were stereoselective and gave up to quan ...[more]

PMID: 31557043

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