Oxidation of p‐Cresol to p‐Hydroxybenzaldehyde with Molecular Oxygen in the Presence of CuMn‐Oxide Heterogeneous Catalyst

A high‐yield synthesis of p‐hydroxybenzaldehyde from p‐cresol and molecular oxygen was achieved over a CuMn‐oxide supported carbon catalyst. The reaction parameters such as pressure, stirring speed, reaction temperature, solvent, and the amount of sodium hydroxide in the reaction media were optimized. As a result, a high conversion of p‐cresol (99%) and a high selectivity to p‐hydroxybenzaldehyde (96%) were realized at the same time. Catalyst separation and recycling tests clearly showed that the reaction proceeded on the heterogeneous catalyst but not on dissolved species.