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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
Homogeneous catalytic hydrogenation of amides to amines
Jacorien Coetzee1, Deborah L Dodds, Jürgen Klankermayer
1EastChem, School of Chemistry, North Haugh, University of St. Andrews, St. Andrews, Fife, KY16 9ST, Scotland, UK.
Abstract:
Hydrogenation of amides in the presence of [Ru(acac)3] (acacH=2,4-pentanedione), triphos [1,1,1-tris- (diphenylphosphinomethyl)ethane] and methanesulfonic acid (MSA) produces secondary and tertiary amines with selectivities as high as 93% provided that there is at least one aromatic ring on N. The system is also active for the synthesis of primary amines. In an attempt to probe the role of MSA and the mechanism of the reaction, a range of methanesulfonato complexes has been prepared from [Ru(acac)3], triphos and MSA, or from reactions of [RuX(OAc)(triphos)] (X=H or OAc) or [RuH2(CO)(triphos)] with MSA. Crystallographically characterised complexes include: [Ru(OAc-κ(1)O)2(H2O)(triphos)], [Ru(OAc-κ(2)O,O')(CH3SO3-κ(1)O)(triphos)], [Ru(CH3SO3-κ(1)O)2(H2O)(triphos)] and [Ru2(μ-CH3SO3)3(triphos)2][CH3SO3], whereas other complexes, such as [Ru(OAc-κ(1)O)(OAc-κ(2)O,O')(triphos)], [Ru(CH3SO3-κ(1)O)(CH3SO3-κ(2)O,O')(triphos)], H[Ru(CH3SO3-κ(1)O)3(triphos)], [RuH(CH3SO3-κ(1)O)(CO)(triphos)] and [RuH(CH3SO3-κ(2)O,O')(triphos)] have been characterised spectroscopically. The interactions between these various complexes and their relevance to the catalytic reactions are discussed.
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