Mechanism of the Asymmetric Hydrogenation of Exocyclic a,P-Unsaturated Carbonyl Compounds with an Iridium/BiphPhox Catalyst: NMR and DFT Studies

摘要

The mechanism of the asymmetric hydrogenation of exocyclic afi-unsaturated carbonyl compounds with the (aS)-Ir/iPr-BiphPhox catalyst was studied by NMR experiments and DFT computational analyses. Computed optical yields of the asymmetric hydrogenation proceeding by an iridium(I)/ iridium(III) mechanism involving a transition state stabilized through two intramolecular hydrogen bonds are in good accordance with the experimental ee values.