Aerobic oxidation of alpha-hydroxyketones catalysed by cobalt(III) and iron(III) complexes under homogeneous and heterogeneous conditions

Aromatic alpha-hydroxyketones were easily oxidized by dioxygen in the presence of excess aldehyde or aldoacetal with catalytic amount of Co(II) or Fe(III) complexes, under homogeneous and heterogeneous conditions. Co(acac), or Fe(acac), were the catalysts used in homogeneous phase reactions whereas Co(LI) or Fe(III) supported complexes, obtained by copolymerization of Co(AAEMA)(2) or Fe(AAEMA)(3) (AAEMA(-) = deprotonated form of 2-(acetoacetoxy)ethyl methacrylate) with acrylamides, were the heterogeneous catalysts. The supported metal complexes were recyclable and did not suffer from metal leaching.