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Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones.

ABSTRACT: Asymmetric hydrogenation of conjugated enones is one of the most efficient and straightforward methods to prepare optically active ketones. In this study, chiral bidentate Ir-N,P complexes were utilized to access these scaffolds for ketones bearing the stereogenic center at both the α- and β-positions. Excellent enantiomeric excesses, of up to 99%, were obtained, accompanied with good to high isolated yields. Challenging dialkyl substituted substrates, which are difficult to hydrogenate with satisfactory chiral induction, were hydrogenated in a highly enantioselective fashion.

SUBMITTER: Peters BBC

PROVIDER: S-EPMC7884017 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones.

Peters Bram B C BBC Jongcharoenkamol Jira J Krajangsri Suppachai S Andersson Pher G PG

Organic letters 20201222 1

Asymmetric hydrogenation of conjugated enones is one of the most efficient and straightforward methods to prepare optically active ketones. In this study, chiral bidentate Ir-N,P complexes were utilized to access these scaffolds for ketones bearing the stereogenic center at both the α- and β-positions. Excellent enantiomeric excesses, of up to 99%, were obtained, accompanied with good to high isolated yields. Challenging dialkyl substituted substrates, which are difficult to hydrogenate with sat ...[more]

PMID: 33351634

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