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Updated: Sep 4, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ligand-Controlled Cobalt-Catalyzed Regiodivergent Alkyne Hydroalkylation
Yan Li1, Deguang Liu1, Lei Wan1
1Department of Hepatobiliary Surgery, The First Affiliated Hospital, Division of Life Sciences and Medicine, Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, University of Science and Technology of China, 230026 Hefei, China.
Abstract:
Regiodivergent alkyne hydroalkylation to generate different isomers of an alkene from the same alkyne starting material would be beneficial; however, it remains a challenge. Herein, we report a ligand-controlled cobalt-catalyzed regiodivergent alkyne hydroalkylation. The sensible selection of bisoxazoline (L1) and pyridine-oxazoline (L8) ligands led to reliable and predictable protocols that provided (E)-1,2-disubstituted and 1,1-disubstituted alkenes with high E/Z stereoselectivity and regioisomeric ratio starting from identical terminal alkyne and alkyl halide substrates and produced trisubstituted alkenes in the case of internal alkynes. This method exhibits a broad scope for terminal and internal alkynes with a wide range of activated and unactivated alkyl halides and shows excellent functional group compatibility.
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