Abstract: | The oxidation of cinnamaldehyde (3-phenyl-2-propenal) by alkaline peroxide results in epoxidation of the double bond to form cinnamaldehyde epoxide (3-phenyl-2,3-epoxy-propanal) which undergoes further reaction by ring opening and side chain cleavage to yield benzaldehyde and acidic fragments. The reactions are first-order in the organic substrates and perhydroxyl anion and second-order overall. In the presence of alkali alone, two further reactions take place in which cinnamaldehyde and cinnamaldehyde epoxide side chains are cleaved by reaction with hydroxide ion to form benzaldehyde and side chain fragments. These reactions are first-order in the organic substrates and hydroxide ion and second-order overall. Increasing solvent polarity accelerates the rates of reaction and reaction mechanisms have been proposed to describe the observed kinetic behavior. The stereoselectivity of the epoxidation reaction has been examined in terms of an existing model for epoxidation of α, β-unsaturated ketones by alkaline peroxide. © 1993 John Wiley & Sons, Inc. |