Selective oxidation of 1,6-hexanediol to 6-hydroxycaproic acid over reusable hydrotalcite-supported au-pd bimetallic catalysts

Abstract

Selective oxidation of 1,6-hexanediol into 6-hydroxycaproic acid was achieved over hydrotalcite-supported Au-Pd bimetallic nanoparticles as heterogeneous catalyst using aqueous H2O2. N,N-dimethyldodecylamine N-oxide (DDAO) was used as an efficient capping agent. Spectroscopic analyses by UV/Vis, TEM, XPS, and X-ray absorption spectroscopy suggested that interactions between gold and palladium atoms are responsible for the high activity of the reusable Au40Pd60-DDAO/HT catalyst. Talcite assumptions: Au-Pd nanoparticles stabilized by N,N-dimethyldodecylamine N-oxide (DDAO) and on a hydrotalcite support are prepared. The supported nanoparticles are employed for the selective oxidation of 1,6-hexanediol to 6-hydroxycaproic acid in alkaline medium with 30% aq. H2O2 as oxidant. Analysis of the catalysts by a combination of spectroscopic techniques reveals electronic interactions between gold an palladium that are responsible for the catalytic performance.