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Updated: Sep 2, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Cobalt-catalyzed branched selective hydroallylation of terminal alkynes
Jieping Chen1, Jiale Ying1, Zhan Lu2,3
1Center of chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
Abstract:
Here, we reported a cobalt-hydride-catalyzed Markovnikov-type hydroallylation of terminal alkynes with allylic electrophile to access valuable and branched skipped dienes (1,4-dienes) with good regioselectivity. This operationally simple protocol exhibits excellent functional group tolerance and exceptional substrate scope. The reactions could be carried out in gram-scale with TON (turn over number) up to 1160, and the products could be easily derivatized. The preliminary mechanism of electrophilic allylation of α-selective cobalt alkenyl intermediate was proposed based on deuterium labeling experiment and kinetic studies.
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