ENANTIOSELECTIVE EPOXIDATION OF CIS-2-HEPTENE WITH HYDROGEN PEROXIDE BY CHLOROPEROXIDASE ENCAPSULATED IN A SILICA GEL

The immobilization of enzymes in porous materials is a useful technique to enhance their stability under relatively harsh conditions in view of their possible use as a catalyst in organic reactions. Chloroperoxidase (CPO) from Caldariomyces Fumago has been encapsulated into a microporous silica prepared by a one-pot sol-gel approach. The as-obtained material was characterized and tested as a catalyst in the enantioselective epoxidation of cis-2-heptene using hydrogen peroxide as oxidant. Different reaction conditions (temperature, pH, cis-2-heptene/H2O2 ratio, amount of catalyst, H2O2 concentration) were modified in order to optimize conversion and enantiomeric excess (ee). The encapsulated CPO can be easily recovered from the reaction mixture and successfully used for a new catalytic cycle, retaining its activity and enantioselectivity.