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Updated: Aug 22, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Intramolecular cyclization of ene-imine using dibutylzirconocene
Muneyoshi Makabe1, Yoshihiro Sato, Miwako Mori
1Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Abstract:
The reaction of ene-imine with Cp(2)ZrBu(2) was carried out. When a crude imine, which was prepared from ene-aldehyde and primary amine in the presence of MgSO(4), was treated with Cp(2)ZrBu(2) at room temperature overnight, cyclopentane derivative having trans-substituents was obtained in high yield along with a small amount of cyclopentane derivative having cis-substituents. Presumably, cis-zirconacycle is a thermodynamic product. Reactions using various ene-imines were carried out. In the case of ene-imine prepared from ene-aldehyde and (t)BuNH(2), only cyclopentane having cis-substituents was produced. In this reaction, chiral amine was used, and diastereoselective cyclization of ene-imine was carried out. As a result, cyclopentane derivative having cis-substituents was obtained in an optically active form after hydrogenolysis of the cyclized compound.
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