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Updated: Oct 21, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
CoIII-Catalyzed C-H Alkenylation and Allylation with Cyclopropenes via Sequential C-H/C-C Bond Activation
Ye Lim Kim1, Sun-A Park1, Seoung-Mi Choi1
1Department of Chemistry (BK21 FOUR), Research Institute of Natural Science, Gyeongsang National University, 52828, Jinju, Korea.
Abstract:
An atom-economical strategy for the C-H alkenylation and C-H allylation of arenes by employing cyclopropenes as versatile alkenylating and allylating reagents is reported, catalyzed by cobalt. The Co-catalyzed C-H alkenylation process involves sequential C-H and C-C bond cleavage. Under the optimized conditions, broad-ranging alkenylated (hetero)arenes were synthesized with complete (E)-stereoselectivity (up to 91%). The consecutive C-H allylation proved viable under basic conditions via double-bond migration of the initially generated alkenyl (hetero)arenes, thus leading to allylated (hetero)arenes with high stereoselectivity of olefin (E/Z ratio = 91:9 to 100:0).
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