微波辐射下肉桂酸的合成研究

研究了微波辐射下肉桂酸的Knoevenagel-Doebner合成新方法。以工本甲醛为反应底物,丙二酸为试剂,吡啶作溶剂,苯胺作催化剂,考察了苯甲醛与丙二酸的摩尔比、微波功率、反应时间、催化剂用量等对反应的影响。经正交实验设计得到最佳反应条件：丙二酸用量为2．510g,丙二酸与苯甲醛摩尔比1．20,苯胺用量0．26mL,微波功率464W,反应时间19min,肉桂酸的产率几乎是定量的。经重结晶后,精产率为67．17％,并分析了有关原因。结果表明,微波技术用于肉桂酸的合成,操作简便、反应迅速、收率高,具有一定的应用价值。

Synthesis of Cinamic Acid under Microwave Irradiation

Microwave irradiation was used to the Knoevenagel-Doebner synthesis of cinamic acid from benzaldehyde and malonic acid using pyridine as a solvent and aniline as a catalyst. The influence of the mol ratio of benzaldehyde and malonic acid, the microwave power, the time of the reaction and the dosage of the catalyst on the yield of cinamic acid was investigated.The optimum reaction condition was determined through orthogonal design as follows: the mol ratio of benzaldehyde and malonic acid was 1.20, the dosage of aniline was 0.26mL, the microwave power was 464W and the time of the reaction was 19min when 2.510g of malonic acid was used.Under the optimum reaction condition the yield of cinamic acid was almost quantitative and the refined yield reached 67.17%. In summary, the microwave technique promotes the synthesis of the cinamic acid with high yield and convenient operation and has extensive utilization.