N-Heterocyclic Carbene-Catalyzed 1,4-Alkylacylation of 1,3-Enynes
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Updated: Oct 13, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Yuxing Cai1, Jiean Chen2, Yong Huang3
1State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
Abstract:
The radical relay coupling reaction recently emerged as a powerful synthetic strategy for producing tetrasubstituted allenes. However, bond-forming processes involving the allenyl radical intermediate are mostly limited to those promoted by transition metals. In this report, we describe that a ketyl radical generated from single-electron oxidation of the Breslow intermediate is an excellent coupling partner of allenyl radicals. An organocatalytic 1,4-alkylacylation of 1,3-enynes occurred smoothly in the presence of an aldehyde, a radical precursor, and an N-heterocyclic carbene catalyst. This transformation showed remarkable tolerance to both aromatic and aliphatic aldehydes, enyne substitution, and diversified radical precursors.
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