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Updated: Oct 7, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Palladium-Catalyzed Siloxycyclopropanation of Alkenes Using Acylsilanes
Shun Sakurai1, Tetsuya Inagaki1, Takuya Kodama1,2
1Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
Abstract:
Currently, catalytically transferable carbenes are limited to electron-deficient and neutral derivatives, and electron-rich carbenes bearing an alkoxy group (i.e., Fischer-type carbenes) cannot be used in catalytic cyclopropanation because of the lack of appropriate carbene precursors. We report herein that acylsilanes can serve as a source of electron-rich carbenes under palladium catalysis, enabling cyclopropanation of a range of alkenes. This reactivity profile is in sharp contrast to that of metal-free siloxycarbenes, which are unreactive toward normal alkenes. The resulting siloxycyclopropanes serve as valuable homoenolate equivalents, allowing rapid access to elaborate β-functionalized ketones.
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