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Updated: May 10, 2026

Catalytic Reactions at Amine-Stabilized and Ligand-Free Platinum Nanoparticles Supported on Titania During Hydrogenation of Alkenes and Aldehydes
Published on: June 24, 2022
A detailed kinetic analysis of rhodium-catalyzed alkyne hydrogenation
Jingwei Luo1, Allen G Oliver, J Scott McIndoe
1Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, BC V8W3V6, Canada.
Abstract:
Continuous monitoring using electrospray ionisation mass spectrometry (ESI-MS) shows that Wilkinson's catalyst hydrogenates a charge-tagged alkyne to the corresponding alkene, and at only a marginally slower rate, to the alkane. No rhodium-containing intermediates were observed during the reaction, consistent with the established mechanism which points at the initial dissociation of triphenylphosphine from Rh(PPh₃)₃Cl as being the key step in the reaction. A numerical model was constructed that the closely matched the experimental data, and correctly predicted the response of the reaction to the addition of excess PPh₃.
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