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Updated: Aug 29, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Lewis acid-promoted cyclization of heteroatom-substituted enynes
Shoko Yamazaki1, Kuriko Yamada, Kagetoshi Yamamoto
1Department of Chemistry, Nara University of Education, Takabatake-cho, Nara 630-8528, Japan. yamazaks@nara-edu.ac.jp
Abstract:
Lewis acid-promoted cyclizations of heteroatom-substituted enynes have been examined. The reaction of enynes and bearing silicon substituents on an alkyne afforded the halogenated five-membered gamma-lactones and gamma-lactams as the main products. The reaction of substrates and having 2-phosphonoacrylate instead of malonate also gave halogenated five-membered cyclic compounds and as the major products. The cyclized products are highly substituted and potentially useful for further synthetic transformations.
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