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Published on: June 21, 2017
Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones
Bram B C Peters1, Jira Jongcharoenkamol1, Suppachai Krajangsri1
1Department of Organic Chemistry, Stockholm University, Arrhenius Laboratory, 106 91, Stockholm, Sweden.
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.
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