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Updated: Dec 30, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Enantioselective Iridium-Catalyzed α-Allylation with Aqueous Solutions of Acetaldehyde
Tobias Sandmeier1, Erick M Carreira1
1ETH Zürich , Vladimir-Prelog-Weg 3, HCI , 8093 Zürich , Switzerland.
Abstract:
The enantioselective α-allylation of aqueous solutions of acetaldehyde using iridium- and amine-catalyzed substitution of racemic allylic alcohols is described. The method utilizes a readily available, safely handled aqueous solution of acetaldehyde and furnishes γ,δ-unsaturated aldehydes in good yields and greater than 99% enantiomeric excess. The synthetic potential of the method is demonstrated with the enantioselective formal syntheses of heliannuols C and E as well as heliespirones A and C.
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