Chemo-enzymatic cascade oxidation in supercritical carbon dioxide/water biphasic media

Abstract

Enantioselective sulfoxidation was carried out by cascade reaction of Pd(0) catalysed formation of H₂O₂ and enzymatic oxidation using chloroperoxidase from Caldariomyces fumago. Supercritical carbon dioxide (scCO₂) was used as medium for in situ generation of H₂O₂ directly from H₂ and O₂ using Pd-catalysts. Subsequently, H₂O₂ was utilised by the chloroperoxidase as an oxidant for the asymmetric sulfoxidation in the aqueous phase. This chemo-enzymatic cascade transformation exemplifies the potential of compartmentalisation of catalytic processes in multiphase systems.