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Updated: Feb 24, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Synthesis of α,β-Unsaturated Ketones from Aldehydes and Ketones Using 1,1-Di(boryl)alk-1-enes
Hiro Takayanagi1, Rikako Masui1, Manami Mori1
1Division of Applied Chemistry, Okayama University, Tsushimanaka, Okayama 700-8530, Japan.
Abstract:
An efficient method for the synthesis of α,β-unsaturated ketones through the boron-Wittig reaction of aldehydes and ketones using 1,1-di(boryl)alk-1-enes is reported. 1,1-Di(boryl)alk-1-enes are deprotonated at the γ-position to generate α,α-di(boryl)allyl anions, which react with aldehydes and ketones at the α-position to give boryl-1,3-dienes. Subsequent oxidation of the resulting boryl-1,3-dienes produces α,β-unsaturated ketones. Furthermore, α,β,γ,δ-unsaturated ketones were also synthesized using 1,1-di(boryl)alka-1,3-dienes.
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