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Updated: Jun 14, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Catalytic Asymmetric Intramolecular Domino Allylic O-Alkylation/Allylic Dearomatization of Allyl Aryl Ethers
Yun-Qiao Zhang1, Ying-Long Li1, Ke-Xu Wang1
1State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
Abstract:
An intramolecular asymmetric allylic O-alkylation/allylic dearomative spirocyclization cascade has been successfully developed with allyl aryl ethers. In the presence of palladium and a phosphoramidite ligand, a series of spirocyclohexadienones with an exocyclic double bond were obtained in up to 98% yield with 98% ee. The asymmetric allylic alkylation mechanism was elucidated through control experiments. In addition, scale-up of the reaction and further transformations of the spirocyclic products were also performed, demonstrating the potential application of this method.
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