Evidence for an enolate mechanism in the asymmetric Michael reaction of α,β-unsaturated aldehydes and ketones via a hybrid system of two secondary amine catalysts.

Chemical Science
Nariyoshi UmekuboYujiro Hayashi

Abstract

The key nucleophile was found to be neither an enamine nor an enol, but an enolate in the direct Michael reaction of α,β-unsaturated aldehydes and non-activated ketones catalyzed by two amine catalysts namely diphenylprolinol silyl ether and pyrrolidine. This is a rare example of an enolate from a ketone serving as a key intermediate in the asymmetric organocatalytic reaction involving secondary amine catalysts because the ketone enolates are generally generated using a strong base, and the enamine is a common nucleophile in this type of reaction.

References

Jan 20, 2005·Angewandte Chemie·Mauro MarigoKarl Anker Jørgensen
Nov 30, 2006·Angewandte Chemie·Claudio Palomo, Antonia Mielgo
May 28, 2008·Chemistry, an Asian Journal·Antonia Mielgo, Claudio Palomo
Sep 18, 2008·Angewandte Chemie·Sami LakhdarHerbert Mayr
Apr 9, 2009·Chemistry, an Asian Journal·Mahendra P Patil, Raghavan B Sunoj
Aug 19, 2011·Accounts of Chemical Research·Kim L JensenKarl Anker Jørgensen
Feb 11, 2014·Journal of the American Chemical Society·Simon KrautwaldErick M Carreira
Oct 2, 2015·Angewandte Chemie·Bjarke S DonslundKarl Anker Jørgensen
Aug 23, 2016·Journal of the American Chemical Society·Xiaohong HuoWanbin Zhang
Dec 16, 2016·Journal of the American Chemical Society·Xingyu JiangJohn F Hartwig
Jan 12, 2017·Journal of the American Chemical Society·Faben A Cruz, Vy M Dong
Jan 6, 2018·Journal of the American Chemical Society·Liang WeiChun-Jiang Wang
Apr 15, 2018·Chemistry : a European Journal·Vladislav A RoytmanMathew Vetticatt
Feb 13, 2019·Chemical Reviews·Gabriel J Reyes-RodríguezKarl Anker Jørgensen

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Citations

Feb 23, 2021·Accounts of Chemical Research·Yujiro Hayashi
Nov 25, 2020·Organic Letters·Nariyoshi Umekubo, Yujiro Hayashi

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