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Updated: Dec 8, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Z-Selective Alkyne Functionalization Catalyzed by a trans-Dihydride N-Heterocyclic Carbene (NHC) Iron Complex
Subhash Garhwal1, Natalia Fridman1, Graham de Ruiter1
1Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, 3200008 Haifa, Israel.
Abstract:
The Z-selective functionalization of terminal alkynes is a useful transformation in organic chemistry and mainly catalyzed by noble metals. Here, we present the Z-selective hydroboration of terminal alkynes catalyzed by a stable trans-dihydride iron complex [(PCNHCP)Fe(H)2N2)] (2). Overall, the reaction occurs at room temperature and provides near quantitative yields of the Z-vinylboronate ester. Interestingly, the same catalyst could also provide the E-vinylboronate by heating the reaction mixture at slightly elevated temperatures (50 °C). If, however, the reaction is performed in the absence of HBpin, rapid Z-selective alkyne dimerization is observed, which is further discussed in this report.
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