Application of gold catalysts to selective liquid phase oxidation

New applications of gold catalysts for selective oxidation of organic molecules are reported. All reactions investigated were performed using molecular oxygen in aqueous solution under mild conditions. Polyhydroxylated aliphatic molecules can be oxidised to monocarboxylates with high selectivity towards the primary alcoholic group in the presence of alkali, whereas the phenyl group enhances the reactivity of a benzylic alcoholic group as it limits the selectivity to mandelate starting from phenyl-1,2-ethanediol. α- and β-aminoalcohols react slowly with oxygen in the absence and quickly in the presence of alkali to produce the corresponding aminoacid derivatives. Aliphatic aldehydes and glucose are easily oxidised to free carboxylic acid. A comparison of gold catalysts and conventional Pd and Pt monometallic, bimetallic and tricomponent catalysts has, in some cases, been done.