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N-Heterocyclic carbenes as chiral Bronsted base catalysts: a highly diastereo- and enantioselective 1,6-addition reaction.

ABSTRACT: Highly diastereo- and enantioselective 1,6-addition of 1,3-ketoamides to p-quinone methides (p-QMs) using chiral NHCs as Brønsted base catalysts is developed. The reaction is based on the utilization of a 1,3-ketoamide having acidic N-H that forms a chiral ion-pair consisting of the enolate and the azolium ion. Different ?-ketoamides and functionalized p-QMs are applicable to the reaction. Synthetic application of the method is demonstrated via the preparation of highly enantioenriched ? and ?-lactam derivatives.

SUBMITTER: Santra S

PROVIDER: S-EPMC6144034 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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N-Heterocyclic carbenes as chiral Brønsted base catalysts: a highly diastereo- and enantioselective 1,6-addition reaction.

Santra Surojit S Porey Arka A Jana Barun B Guin Joyram J

Chemical science 20180702 30

Highly diastereo- and enantioselective 1,6-addition of 1,3-ketoamides to p-quinone methides (p-QMs) using chiral NHCs as Brønsted base catalysts is developed. The reaction is based on the utilization of a 1,3-ketoamide having acidic N-H that forms a chiral ion-pair consisting of the enolate and the azolium ion. Different β-ketoamides and functionalized p-QMs are applicable to the reaction. Synthetic application of the method is demonstrated via the preparation of high ...[more]

PMID: 30288232

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