β-Cyclodextrin polymer promoted green synthesis of cinnamaldehyde to natural benzaldehyde in aqueous solution

Abstract

An environmentally benign synthesis of natural benzaldehyde from cinnamaldehyde under mild conditions has been investigated with sodium hypochlorite as oxidant and β-cyclodextrin polymer as phase-transfer catalyst. The polymer showed excellent catalytic activity exhibiting 92% conversion and 62% selectivity to benzaldehyde at ambient pressure and at 70°C. This catalyst could be recovered and reused six times, and the catalyst efficiency remained unchanged, which suggests that the catalyst is an efficient and green catalyst for oxidation of cinnamaldehyde. The results reported herein may be a promising method in industry for the synthesis of natural benzaldehyde.

Keywords:

• phase-transfer catalyst
• benzaldehyde
• sodium hypochlorite
• β-cyclodextrin polymer
• mechanism

Acknowledgements

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