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Updated: Nov 18, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ni-catalyzed regio- and stereo-defined intermolecular cross-electrophile dialkylation of alkynes without directing
Yi-Zhou Zhan1, Nan Xiao1, Wei Shu2
1Shenzhen Grubbs Institute, Department of Chemistry, and Guangdong Provincial Key Laboratory of Catalytic Chemistry, Southern University of Science and Technology, 518055, Shenzhen, Guangdong, P. R. China.
Abstract:
The development of straightforward synthesis of regio- and stereodefined alkenes with multiple aliphatic substituents under mild conditions is an unmet challenge owing to competitive β-hydride elimination and selectivity issues. Herein, we report the nickel-catalyzed intermolecular cross-dialkylation of alkynes devoid of directing or activating groups to afford multiple aliphatic substituted alkenes in a syn-selective fashion at room temperature. The combination of two-electron oxidative cyclometallation and single-electron cross-electrophile coupling of nickel enables the syn-cross-dialkylation of alkynes at room temperature. This reductive protocol enables the sequential installation of two different alkyl substituents onto alkynes in a regio- and stereo-selective manner, circumventing the tedious preformation of sensitive organometallic reagents. The synthetic utility of this protocol is demonstrated by efficient synthesis of multi-substituted unfunctionalized alkenes and diverse transformations of the product.
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