Asymmetric Michael Addition of Arylthiols to α,β-Unsaturated Carbonyl Compounds Catalyzed by Bifunctional Organocatalysts

Bang-Jing Li; Lin Jiang; Min Liu; Ying-Chun Chen; Li-Sheng Ding; Yong Wu

doi:10.1055/s-2005-863710

LETTER

Asymmetric Michael Addition of Arylthiols to α,β-Unsaturated Carbonyl Compounds Catalyzed by Bifunctional Organocatalysts

Bang-Jing Li^b, Lin Jiang^a, Min Liu^a, Ying-Chun Chen*^a, Li-Sheng Ding^b, Yong Wu^a
^a Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
Fax: +86(28)85502609; e-Mail: ycchenhuaxi@yahoo.com.cn;
^b Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, P. R. China

Abstract

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Abstract

Bifunctional chiral organocatalysts comprising thiourea and tertiary amine groups were synthesized. They act as efficient catalysts for asymmetric Michael addition of arylthiols to α,β-unsaturated carbonyl compounds. Enantioselectivity up to 85% has been achieved. Asymmetric α-protonation reaction (up to 60% ee) can be obtained in the presence of the bifunctional catalyst.

Key words

bifunctional organocatalyst - thiourea - hydrogen bonding - asymmetric Michael addition - asymmetric protonation

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References

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