MRC  Vol.3 No.3 , July 2014
The Nature of the True Catalyst in Transfer Hydrogenation with Alcohol Donors Using (arene)2Ru2Cl4(II)/TsDPEN Precursor
Abstract: The widespread precatalyst (prepared in-situ or ex-situ) (arene) RuTsDPEN advocated for highly effectual asymmetric transfer hydrogenation (ATH) reactions with 2-propanol as hydrogen donor at ambient conditions, is proven to be unstable under the strong reducing conditions prevailing in the reaction mixtures (blend of alcohol and a base such as KOH). We assert that the true catalysts are the ruthenium metal nanoclusters formed swiftly under the reducing conditions of these systems. The TsDPEN ligand plays a critical role in the generation and formatting of the active catalyst including wreaking chiral properties to the so formed catalytic nanoparticles. Kinetic measurements, NMR, UV-visible spectroscopy, circular dichroism (CD) and TEM analyses corroborate this argument.
Cite this paper: Toubiana, J. , Medina, L. and Sasson, Y. (2014) The Nature of the True Catalyst in Transfer Hydrogenation with Alcohol Donors Using (arene)2Ru2Cl4(II)/TsDPEN Precursor. Modern Research in Catalysis, 3, 68-88. doi: 10.4236/mrc.2014.33010.

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