Improvement of the Synthetic Experiment of Benzocaine Based on Biocatalysis
WANG Jin-Li1, DING Rui2, ZHANG Shou-Lin1*, ZHANG Xing2*, XIE Lan-Gui1*
1. School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China; 2. School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China
Abstract The preparation of benzocaine is an important organic experiment in teaching laboratory for college students. Currently, the general experimental plan is esterifying para-nitrobenzoic acid with ethanol in the presence of concentrated sulfuric acid, following by the reduction of ethyl nitrobenzoate with iron powder and hydrochloric acid, to afford the benzocaine product. In this paper, the technologies of ultrasonic assisted synthesis andbiocatalysiswere introduced into the steps of esterification and the reduction of nitro group, respectively, which allowed the reactions could be conducted under mild and environmentally friendly conditions. This new experimental program successfully avoided the use of highly corrosive sulfuric acid or hydrochloric acid, as well as the generation environmental unfriendly by-products, by applying the concept of biocatalysis into the fundamentally experimental training, leading to a teaching experiment with distinguished advantages on operational safety and green synthesis.
WANG Jin-Li, DING Rui, ZHANG Shou-Lin, ZHANG Xing, XIE Lan-Gui. Improvement of the Synthetic Experiment of Benzocaine Based on Biocatalysis[J]. Chinese Journal of Chemical Education, 2023, 44(12): 32-36.