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Updated: Oct 25, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Photochemical Aldehyde-Olefin Coupling via In Situ Activation of α-Benzoyloxy Chlorides
1South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou510640, China.
Abstract:
While ketyl radicals enable powerful umpolung C(sp3)-C(sp3) couplings, their generation from aliphatic aldehydes typically requires metal reductants or precious-metal catalysts. Herein, we report a practical photochemical protocol for one-pot aldehyde-olefin cross-coupling. This method leverages the in situ formation of α-benzoyloxy chlorides, which undergo direct reduction by a photoexcited Hantzsch ester to afford ketyl-type radicals. This mild strategy features operational simplicity, broad functional group tolerance, and enables late-stage modification of bioactive molecules.
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