Solvent-Free Benzyl Alcohol Oxidation Using Spatially Separated Carbon-Supported Au and Pd Nanoparticles

The spatial separation of Au and Pd nanoparticles supported on carbon has been demonstrated to be highly effective in facilitating aqueous-phase alcohol oxidation reactions, wherein OH– is the oxidant terminal for the oxidative dehydrogenation reaction. However, the application of this methodology in nonaqueous environments has not yet been explored. Supported alloyed Au–Pd nanoparticles are known to be highly active in the solvent-free oxidation of benzyl alcohol with oxygen as the terminal oxidant, leading to benzaldehyde by direct oxidation and toluene by disproportionation. Here, we show that by physically separating Au and Pd nanoparticles supported on carbon, the reaction rate for solvent-free benzyl alcohol oxidation can be further enhanced by coupling the oxidation and disproportionation reactions via H-transfer from Pd to Au.