Catalytic Oxidation of Alcohol via Nickel Phosphine Complexes with Pendant Amines

Nickel complexes were prepared with
diphosphine ligands that contain
pendant amines, and these complexes catalytically oxidize primary
and secondary alcohols to their respective aldehydes and ketones.
Kinetic and mechanistic studies of these prospective electrocatalysts
were performed to understand what influences the catalytic activity.
For the oxidation of diphenylmethanol, the catalytic rates were determined
to be dependent on the concentration of both the catalyst and the
alcohol and independent of the concentration of base and oxidant.
The incorporation of pendant amines to the phosphine ligand results
in substantial increases in the rate of alcohol oxidation with more
electron-donating substituents on the pendant amine exhibiting the
fastest rates.