Oxidative cleavage of C = C bond of cinnamaldehyde to benzaldehyde in the presence of β-cyclodextrin under mild conditions

Abstract

Efficient oxidative cleavage of cinnamaldehyde to benzaldehyde by hydrogen peroxide in the presence of β-cyclodextrin (β-CD) and sodium bicarbonate in water has been developed. β-CD showed excellent activity for the oxidation under mild conditions. The effects of different reaction conditions, e.g. reaction temperature, the amount of β-CD, sodium bicarbonate and hydrogen peroxide concentrations, etc. have been investigated. The yield of benzaldehyde could reach 78% under the optimum conditions (333 K, 2 h, molar ratio for cinnamaldehyde:β-CD:sodium bicarbonate = 1:1:12). Moreover, a plausible mechanism including the formation of inclusion complex and the corresponding epoxide was proposed.

Keywords:

• oxidative cleavage
• β-cyclodextrin
• cinnamaldehyde
• natural benzaldehyde
• hydrogen peroxide

Acknowledgements

The authors thank the National Natural Science Foundation of China (nos 21036009 and 21176268), higher-level talent project for Guangdong provincial universities and the Fundamental Research Funds for the Central Universities for providing their financial support to this project.