Solvent–free and Selective Autooxidation of Alkylbenzenes Catalyzed by Co/NHPI under Phase Transfer Conditions

Abstract

Abstract Solvent‐free, selective and sustainable reaction protocol for an autoxidation of alkylbenzenes catalyzed by Co‐NHPI (Cobalt‐N‐hydroxyphthalimide) under PTC (Phase Transfer Conditions) is described. A multigram scale preparation of acetophenone from ethylbenzene oxidation is demonstrated. The effect of catalyst [Cobalt, DDAB (Di‐n‐decyl‐di‐methyl ammonium bromide) and NHPI] concentrations, different types of catalysts, effect of temperature and oxygen pressure as well as reaction kinetics related to present auto‐oxidation of alkylbezenes is studied in details. Light microscope image shows that DDAB has Multi Lamellar Vesicles (MLVs) structures through which it protects NHPI at high temperatures. Thus efficient recovery and reuse of present ternary catalytic system (Co‐NHPI/DDAB) is feasible.