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Updated: Apr 24, 2026
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Cu-Catalyzed Z-Selective Carboboration of Acetylene with Hindered Michael Acceptors Enabled by a Buffering Borinate
Yu Wang1, Tairan Cheng1, Lin Chen1
1Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Abstract:
A copper-catalyzed carboboration of acetylene with Knoevenagel-type Michael acceptors has been achieved by using a bidentate phosphine ligand, affording Z-alkenyl boronates in good to excellent yields. This new catalytic system overcomes the limitations of our earlier NHC-Cu catalytic system. The addition of EtO-9-BBN as a buffering additive effectively suppresses undesired decomposition pathways via reversible interaction with alkoxides to form boronate complexes. The formation of the key boronate intermediate was confirmed by 11B NMR spectroscopy. This strategy offers an efficient route to Z-alkenyl boronates bearing two electron-withdrawing groups, complementing our previous catalytic system.
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