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Updated: Apr 29, 2026
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
N-heterocyclic carbene catalyzed intramolecular acylation of allylic electrophiles
Ming Zhao1, Hui Yang, Miao-Miao Li
1Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Department of Chemistry & Materials Science, Northwest University , Xi'an 710069, P. R. China.
Abstract:
The N-heterocyclic carbene (NHC) catalyzed addition reaction has been well documented recently; however, the NHC-catalyzed substitution reaction especially the SN2' type reaction remains a challenge. As one of the most fundamental reaction types in organic chemistry, the SN2' reaction catalyzed by NHC would be a powerful tool in organic synthesis. Therefore, the first NHC-catalyzed intramolecular SN2' substitution reaction of aldehyde with allylic electrophiles has been developed. A variety of α,β-unsaturated chromanones were obtained under a domino SN2' reaction and isomerization. Mechanistic experiments were conducted to confirm the nature of this SN2' reaction.
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