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Updated: Oct 2, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Efficient synthesis of tetrasubstituted alkenes by allylsilane-terminated domino-Heck double cyclisation
Lutz F Tietze1, Klaus Kahle, Thomas Raschke
1Institut für Organische Chemie der Georg-August-Universität Göttingen, Germany. ltietze@gwdg.de
Abstract:
The domino-Heck double cyclisation of the arylbromides 1, which contain an allylsilane and an alkyne moiety and are easily accessible by an addition of the corresponding lithiated alkynes 5 to the aldehydes 4, leads to the tetrasubstituted alkenes 2 and 3 in good yield. The reaction produces exclusively compounds with an E double bond and additionally proceeds with good to excellent induced diastereoselectivity in the case of 1e and 1f. Irradiation of 2e leads to a steady state equilibrium of the E and Z compounds in a 1:1 ratio.
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