Asymmetric epoxidation of cinnamyl alcohol catalyzed by silica-supported casein-Co complex

Silica-supported casein–Co complex (Si-CA–Co) was prepared from silica, casein and cobalt chloride, and found to be useful as a chiral catalyst for the asymmetric epoxidation of cinnamyl alcohol to (2R,3R)-(+)-3-phenylglycidol at 70 °C and under 1 atmospheric oxygen pressure. When a proper content of cobalt in the Si-CA–Co complex and suitable reaction conditions were selected, the product and optical yield could be amounted to 70.6 and 92.0%, respectively, and the Si-CA–Co complex could be reused several times without any remarkable change in the optical catalytic activity. Copyright © 2002 John Wiley & Sons, Ltd.