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Updated: Jul 26, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Asymmetric imino-acylation of alkenes enabled by HAT-photo/nickel cocatalysis
1Hefei National Laboratory for Physical Science at the Microscale, Department of Chemistry, Center for Excellence in Molecular Synthesis, University of Science and Technology of China 96 Jinzhai Road Hefei Anhui 230026 P. R. China chuanw@ustc.edu.cn.
Abstract:
By merging nickel-mediated facially selective aza-Heck cyclization and radical acyl C-H activation promoted by tetrabutylammonium decatungstate (TBADT) as a hydrogen atom transfer (HAT) photocatalyst, we accomplish an asymmetric imino-acylation of oxime ester-tethered alkenes with readily available aldehydes as the acyl source, enabling the synthesis of highly enantioenriched pyrrolines bearing an acyl-substituted stereogenic center under mild conditions. Preliminary mechanistic studies support a Ni(i)/Ni(ii)/Ni(iii) catalytic sequence involving the intramolecular migratory insertion of a tethered olefinic unit into the Ni(iii)-N bond as the enantiodiscriminating step.
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