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Updated: Aug 2, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
The first catalytic asymmetric addition of dialkylzincs to alpha-ketoesters
Erin F DiMauro1, Marisa C Kozlowski
1Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Abstract:
[formula: see text] The first catalytic, enantioselective addition of organoznic reagents to alpha-ketoesters is described. Modular bifunctional salen catalysts that contain Lewis acid and Lewis base activating groups accelerate the carbonyl addition to a much greater extent than the competing carbonyl reduction. alpha-Hydroxyesters containing new quaternary stereogenic centers are obtained in high yield and moderate enantiomeric excess. Enrichment to 98% ee can be effected by recrystallization of the corresponding alpha-hydroxy acid.
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