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Updated: Feb 23, 2026
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Gold(III) Alkyne Complexes: Bonding and Reaction Pathways
Luca Rocchigiani1, Julio Fernandez-Cestau1, Gabriele Agonigi1
1School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
Abstract:
The synthesis and characterization of hitherto hypothetical AuIII π-alkyne complexes is reported. Bonding and stability depend strongly on the trans effect and steric factors. Bonding characteristics shed light on the reasons for the very different stabilities between the classical alkyne complexes of PtII and their drastically more reactive AuIII congeners. Lack of back-bonding facilitates alkyne slippage, which is energetically less costly for gold than for platinum and explains the propensity of gold to facilitate C-C bond formation. Cycloaddition followed by aryl migration and reductive deprotonation is presented as a new reaction sequence in gold chemistry.
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02:34Preparation of Alkynes: Dehydrohalogenation
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02:35Electrophilic Addition to Alkynes: Hydrohalogenation