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Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Hydrogen Atom Transfer-Triggered Enantioselective Hydroalkylation of 1,3-Enynes to Chiral Allenes
Yuzhen Li1, Hongyu Wang1, Xiaofan Chen1
1Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu610207, P. R. China.
Abstract:
Asymmetric radical addition to 1,3-enynes represents an efficient strategy for the construction of chiral allenes. Current methods typically rely on prefunctionalized radical precursors and electron-rich 1,3-enynes. Herein, we report a photoinduced enantioselective 1,4-radical hydroalkylation of 2-acyl 1,3-enynes with inert C(sp3)-H compounds. Synergistic catalysis merging a quinone-based hydrogen atom transfer photocatalyst with a chiral N,N'-dioxide/Sc(III) complex was exploited to enable the straightforward synthesis of chiral allenes in high yield and enantioselectivity.
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