Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate.

Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Research Abstract Details 

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Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Abstract Text:

Timothy J Peelen,Yonggui Chi,Samuel H Gellman,

An enantioselective intermolecular Michael addition of aldehydes to enones catalyzed by imidazolidinones has been achieved. Chemoselectivity (Michael addition vs aldol) can be controlled through judicious choice of hydrogen-bond-donating cocatalysts. The optimal imidazolidinone/hydrogen-bond-donor pair affords Michael addition products in excess of 90% ee. Furthermore, we have isolated and characterized an enamine intermediate and demonstrated its efficacy as a nucleophile in the observed Michael addition reactions.

Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Publishing Authors By Initials

TJ Peelen,Y Chi,SH Gellman,

For similar natural sciences: chemistry: chemistry, organic: isomerism: stereoisomerism research abstracts see: natural sciences: chemistry: chemistry, organic: isomerism: stereoisomerism research

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Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Journal Published:

PUBLICATION TYPE: Research Support, U.S. Gov't,

Journal: Journal of the American Chemical Society

VOLUME: 127

Page Numbers: 11598-9

Journal Abbreviation: J. Am. Chem. Soc.

ISSN: 0002-7863

DAY: 24

MONTH: Aug

YEAR: 2005

Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Information

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LANGUAGE: eng

NlmUniqueID: 7503056

Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Keywords Mesh Terms:

KEYWORDS: Stereoisomerism

MESH TERMS: chemistry

Chemical & Substance for Abstract: Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate. Information

Substance Name: Organometallic Compounds

Registry Number: 0

Grant and Affiliation Information for Enantioselective organocatalytic Michael additions of aldehydes to enones with imidazolidinones: cocatalyst effects and evidence for an enamine intermediate.

AFFILIATION: Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.

Country: United States

AGENCY: United States NIGMS

GRANT: GM065713

ACRONYM: GM

MEDLINETA: J Am Chem Soc

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