Mechanistic insights into Cu-catalyzed asymmetric aldol reactions: Chemical and spectroscopic evidence for a metalloenolate intermediate

Angewandte Chemie - International Edition

Volumn 37, Issue 22, 1998, Pages 3124-3126

  Pagenkopf, Brian L ^a   Krüger, Jochen ^a   Stojanovic, Aleksandar ^a   Carreira, Erick M ^a  

^a CALIFORNIA INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

Aldol reactions; Asymmetric catalysis; C C coupling; IR spectroscopy

Indexed keywords

COPPER;

ARTICLE; CATALYSIS; COMPLEX FORMATION; SPECTROMETRY; STEREOCHEMISTRY; SYNTHESIS;

EID: 0345195964     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/(SICI)1521-3773(19981204)37:22<3124::AID-ANIE3124>3.0.CO;2-1     Document Type: Article

References (33)

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30. The IR experiments were conducted with an ASI Applied Systems ReactIR 1000 spectrometer with a MCT detector (MCT = mercury cadmium telluride) and a DiComp probe.
31. In these and all reactions the product was isolated in 91-94% ee, values which are similar to those we routinely obtain for this process under preparative conditions.
32. In a control experiment, the quaternary ammonium dienolate was found to react rapidly with benzaldehyde at - 78 °C to form racemic aldol adduct in 94% yield.
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