肉桂酸的合成研究

Synthesis of Cinnamic Acid

研究了在吡啶介质中,以六氢吡啶为缩合剂,通过苯甲醛与丙二酸的Knoevenagel缩合反应合成了肉桂酸,该法具有工艺简单,产率高,反应无污染,产物分离纯化容易,操作方便等优点。分别研究了反应物配比、缩合剂用量、反应温度、反应时间等因素对合成反应的影响,确定了最佳工艺条件为:苯甲醛与丙二酸物质的量之比为1.0∶1.2,苯甲醛、吡啶与六氢吡啶物质的量之比为1.0∶2.4∶0.025,在95°C下回流2.0h,产率达89.19%,质量分数达98.19%。

Cinnamic acid was synthesized from benzaldehyde and malonic acid by Knoevenagel condensation reaction in pyridine using piperidine as condensation agent. This technology is simple, and gives high yield and no pollution. The factors influencing the synthesis were studied and the optimum conditions were given as follows. The molar ratio of benzaldehyde and malonic acid is 1.0∶1.2, while the moler ratio of benzaldehyde、pyridine and piperidine is 1.0∶2.4∶0.025. The reaction temperature is (95°C) and the reaction time is 2.0 h, The yield of the product is 89.19%, and the purity is 98.19%.