Metal Complex-Catalyzed Epoxidation of Olefins by Dioxygen with Co-Oxidation of Aldehydes. A Mechanistic Study.
Mechanistic studies of the oxidation of olefins by dioxygen plus aldehyde in the presence of metal complexes such as metalloporphyrins and metal cyclam complexes have been carried out. Epoxides were the predominant products, with trace amounts of allylic oxidation products. cis-Stilbene was oxidized to a mixture of cis- and trans-stilbene oxides. It is concluded from this study that the principal role of the metal complexes is to aid in the initiation step for the free radical autoxidation of the aldehyde and that acylperoxy radicals generated in the autoxidation reaction (or metal complexes formed by complexation of the acylperoxy radicals) are the active epoxidizing agents.
Nam
Wonwoo
W
Department of Chemistry, Ewha Womans University, Seoul 120-750, Korea, and Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90024.
Kim
Hyo Jin
HJ
Kim
Seong Hoon
SH
Ho
Raymond Y. N.
RY
Valentine
Joan Selverstone
JS