β-Cyclodextrin Promoted Oxidation of Cinnamaldehyde to Natural Benzaldehyde in Water

A facile and efficient procedure has been developed systematically for the oxidative cleavage of cinnamaldehyde to benzaldehyde by sodium hypochlorite with water as the only solvent in the presence of β-cyclodextrin (abbreviated as β-CD). Different factors influencing cinnamaldehyde oxidation e.g. reaction temperature, the amount of catalyst and oxidant, have been investigated. The yield of benzaldehyde reaches 76% under the optimum conditions (333 K, 4 h, molar ratio of cinnamaldehyde to β-CD is 1:1). Furthermore, a feasible reaction mechanism including the formation of benzaldehyde and the two main byproducts (phenylacetaldehyde and epoxide of cinnamaldehyde) has been proposed.