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Updated: May 23, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Palladium-catalyzed cycloaddition of alkynyl aryl ethers with internal alkynes via selective ortho C-H activation
Yasunori Minami1, Yuki Shiraishi, Kotomi Yamada
1Research and Development Initiative, Chuo University, Kasuga, Tokyo 112-8551, Japan. yminami@kc.chuo-u.ac.jp
Abstract:
Alkynyl aryl ethers react with internal alkynes through selective ortho C-H activation by a palladium(0) catalyst to give substituted 2-methylidene-2H-chromenes. The alkynoxy group acts as a directing group to promote ortho C-H functionalization. Deuterium-labeling experiments indicated that the arylpalladium hydride complex is a key intermediate via oxidative addition. Various functional groups tolerate the present transformation to give the corresponding products.
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