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Updated: May 18, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Nickel-catalyzed intermolecular [2 + 2] cycloaddition of conjugated enynes with alkenes
Akira Nishimura1, Masato Ohashi, Sensuke Ogoshi
1Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
Abstract:
A nickel-catalyzed intermolecular [2 + 2] cycloaddition of conjugated enynes with alkenes has been developed. A variety of electron-deficient alkenes as well as electronically neutral norbornene and 1-decene were applicable to this reaction. The use of conjugated enynes circumvented possible side rections, such as oligomerizations and cyclotrimerizations. The isolation of reaction intermediate complexes revealed that the η(3)-butadienyl coordination is the key for the selective formation of cyclobutene.
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