微波辐射下L-丙氨酸消旋反应研究与优化

Optimization of Microwave-Assisted Rapid Racemization of L-Alanine

微波辐射下的L-丙氨酸消旋反应是一种新的工业化生产方法,具有环保的优点。本文应用单因素轮换试验法考察了反应的影响因素,而后通过响应面分析法对各影响因素进行优化,确定了在微波辐射下,以560W的微波输出功率,用1.2mol/L氢氧化钠水溶液替代乙酸作为反应溶剂,用0.14摩尔比的水杨醛为催化剂,L-丙氨酸可以快速消旋。得出消旋反应随微波辐射功率的提高而加快。同时也讨论了微波作用下L-丙氨酸的消旋反应机理。

A practical method for the racemization of L-Alanine has been developed by microwave irradiation. It is economical, convenient and environmentally acceptable way to racemize L-Alanine. By single factor cyclical method, the factors influencing the racemization were investigated. Finally, by optimization of response surface methodology, the whole process of racemization can be completed within 1 h in a medium of 1.2mol/L NaOH under reflux conditions for in the presence of 0.14 molar equivalent of Salicylaldehyde by using 560W microwave irradiation. It is also showed that the reaction rates is speed up with the increase of the power of microwave. The mechanism of the racemization was discussed.