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Manganese-Catalyzed Hydrogenation of Ketones under Mild and Base-free Conditions.

ABSTRACT: In this paper, several Mn(I) complexes were applied as catalysts for the homogeneous hydrogenation of ketones. The most active precatalyst is the bench-stable alkyl bisphosphine Mn(I) complex fac-[Mn(dippe) (CO)₃(CH₂CH₂CH₃)]. The reaction proceeds at room temperature under base-free conditions with a catalyst loading of 3 mol % and a hydrogen pressure of 10 bar. A temperature-dependent selectivity for the reduction of α,β-unsaturated carbonyls was observed. At room temperature, the carbonyl group was selectively hydrogenated, while the C=C bond stayed intact. At 60 °C, fully saturated systems were obtained. A plausible mechanism based on DFT calculations which involves an inner-sphere hydride transfer is proposed.

SUBMITTER: Weber S

PROVIDER: S-EPMC8155567 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Manganese-Catalyzed Hydrogenation of Ketones under Mild and Base-free Conditions.

Weber Stefan S Brünig Julian J Veiros Luis F LF Kirchner Karl K

Organometallics 20210422 9

In this paper, several Mn(I) complexes were applied as catalysts for the homogeneous hydrogenation of ketones. The most active precatalyst is the bench-stable alkyl bisphosphine Mn(I) complex fac-[Mn(dippe) (CO)3(CH2CH2CH3)]. The reaction proceeds at room temperature under base-free conditions with a catalyst loading of 3 mol % and a hydrogen pressure of 10 bar. A temperature-dependent selectivity for the reduction of α,β-unsaturated carbonyls w ...[more]

PMID: 34054186

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