Download PDF
Synfacts 2006(6): 0611-0611  
DOI: 10.1055/s-2006-941784
Bioorganic Chemistry and Organocatalysis
© Georg Thieme Verlag Stuttgart · New York

Asymmetric Michael Reaction Catalyzed by Chiral Ionic Liquids

Contributor(s): Benjamin List, Daniela Kampen
S. Luo*, X. Mi, L. Zhang, S. Liu, H. Xu, J.-P. Cheng*
Centre of Molecular Science, Beijing and Nankai University, Tianjin, P. R. of China
Further Information

Publication History

Publication Date:
19 May 2006 (online)

    Permissions and Reprints

Significance

Chiral ionic liquids have been developed as catalysts for the asymmetric Michael reaction. Addition of carbonyl compounds 1 to aromatic nitroolefins 2 in the presence of 15 mol% of functionalized ionic liquids 3 and 5 mol% of TFA provides products of type 4 in high yields, enantio­selectivities, and diastereoselectivities. Cyclic ketones, acetone, as well as aliphatic aldehydes can be used. The reaction presumably proceeds via an enamine intermediate. A transition state illustrating the mode of face shielding by the imidazolium moiety to explain the observed relative and absolute configuration is proposed.