肉桂酸合成新工艺研究

肉桂酸是一种重要的有机合成中间体,广泛应用与医药、香料、塑料、感光材料、缓蚀剂和交联剂等产品的生产中。特别是近几年来,其需求量每年以15%～20%的速度迅速增长,市场潜力巨大,供不应求。本文以吡啶为介质,以六氢吡啶为缩合剂,通过苯甲醛与乙酸酐的缩合反应合成了肉桂酸。并对反应物配比、缩合剂用量、反应温度、反应时间等工艺条件进行了研究,确定最佳工艺条件为：苯甲醛与乙酸酐摩尔比为1.0∶1.2,苯甲醛、吡啶与六氢吡啶的摩尔比为1.0∶2.4∶0.025,在160～170℃下回流2.0h,肉桂酸产率达89.19%。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。

Research on New Technology of Synthesizing Cinnamic Acid

Cinnamic acid,an important chemical intermediate in organic synthesis,is widely used in the production of medicine、spice、 plastic、sensitive material、corrosion inhibitor and cross-linking agent.Especially in recent years,the cinnamic acid＇s quantity demanded is rising by 15%～20% every year.Therefore,it has a huge potential market and is in great need.We synthesized cinnamic acid using pyridine as medium and piperidine as condensing agent based on the condensation reaction between benzaldehyde and acetic anhydride,and studied the effect of reactant ratio、condensing agent consumption、temperature、time and so on.The optimum conditions were finally confirmed that the mole ratio of benzaldehyde to acetic anhydride was 1.0∶1.2,and the mole ratio of benzaldehyde： pyridine： piperidine was 1.0∶2.4∶0.025 and the productivity could reach to 89.19% if the reaction time was 2h at 160～170℃.This method is easy,high-yield,pollution-free and the isolation of products is effortless and convenient.