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Asymmetric Michael Reaction of α-CF3 Thioester and α,β-Unsaturated Aldehyde Catalyzed by Diphenylprolinol Silyl Ether
Yujiro Hayashi1, Tomoaki Yamada1, Misaki Sato1
1Department of Chemistry, Graduate School of Science , Tohoku University , 6-3 Aramaki Aza-Aoba , Aoba-ku, Sendai , Miyagi 980-8578 , Japan.
Abstract:
Asymmetric Michael reaction of α-CF3 thioester and α,β-unsaturated aldehyde is catalyzed by diphenylprolinol silyl ether to afford the trifluoromethyl substituted Michael product with excellent enantioselectivity. Although the Michael products were generated as a mixture of syn- and anti-isomers, they can be transformed to single isomers of other useful compounds, such as lactone, lactam, piperidine, dihydropyran containing trifluoromethyl groups, or fluoro substituents.
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