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Updated: Jan 18, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ruthenium-Catalyzed Intermolecular [2 + 2] Cycloaddition of Unactivated Allenes and Alkynes with Unusual
Chaoshen Zhang1, Herman H Y Sung1, Ian D Williams1
1Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR 999077, China.
Abstract:
Described here is an efficient protocol for intermolecular [2 + 2] cycloaddition of unactivated and unsymmetrical allenes and alkynes with unusual regioselectivity, counterintuitively favoring the most hindered isomer. CpRu(MeCN)3PF6 served as a uniquely effective catalyst, providing diverse 3-alkylidenecyclobutenes with a broad scope and good functional group compatibility. Both experiments and DFT studies provided important insights into the mechanism, particularly the unusual regioselectivity.
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