基于绿色化学理念的苯甲醛与安息香的相互转化

Mutual Conversion between Benzaldehyde and Benzoin Based on the Idea of Green Chemistry

为了在基础教学实验中引入绿色化学理念以及强化氧化还原反应操作,本文设计了苯甲醛和安息香的相互转化实验:以苯甲醛为原料经维生素B1催化得到安息香,再用硼氢化钠还原安息香得到二苯乙二醇,二苯乙二醇用新型绿色催化剂NaMnOx氧化回到苯甲醛。通过氢核磁共振(1H NMR)对氧化还原反应的产物结构进行了鉴定,液相色谱分析结果表明氧化反应转化率达到90%以上。通过这一循环转化反应的实现,一方面树立了学生的绿色化学理念,另一方面加强了氧化及还原反应的操作训练,在进一步锻炼学生实验能力的同时,使其对化学反应的认知与评价更加完整。

In order to bring the concept of green chemistry into basic laboratory teaching and to enhance the exercise on redox reactions,we designed an experiment about the mutual conversion between benzoin and benzaldehyde.In this experiment,benzaldehyde is catalyzed by Vitamin B1 to be converted to benzoin,then benzoin is reduced with sodium borohydride into 1,2-diphenyl glycol.Afterwards,the product will be oxidated into benzaldehyde under the catalyzing of new green catalyst NaMnOx.1H NMR was used to authenticate the product in each step of the experiment,and the yield of the oxidation reaction is greater than 90%with HLPC measurement.By completing this cyclic conversion reaction,we conveys the idea of green chemistry to the students,and the students get practice on operating the redox reaction.At the same time,students’cognition and evaluation of chemical reaction can be more complete.