对氟苯甲醛的合成研究

Study on the Synthesis of p-Fluorobenzaldehyde

以对氟甲苯为原料,制备对氟苯甲醛。对氟甲苯在催化剂作用下经氯化、水解、精馏制备对氟苯甲醛。分析氯化反应、水解反应对对氟苯甲醛收率的影响。结果表明:(1)氯化反应时,通氯时间为3h,氯化反应温度为115℃时,对氟二氯苄含量较高;(2)水解反应时,水解温度控制在110~120℃,物质的量n∶n∶n=1∶1.6∶2.5时,得到产物的最高收率达到96%,对氟苯甲醛含量可达99%以上。该方法具有原料易得、反应条件简单、工艺稳定、反应总收率高的特点,并在工业生产中得到运用。

The p-fluorobenzaldehyde is synthesized with p-fluorotoluene as a raw material by the process of chlorination, hydrolysis and distilla-tion of p-fluorotoluene under the action of a catalyst. The influence of chlorination reaction and hydrolysis reaction on the yield of p-fluorobenzalde-hyde is analyzed. The result shows that(1)During the chlorination reaction, the content of p-fluorodichlorobenzyl is higher when the time is 3h for adding chlorine and the chlorination reaction temperature is 115℃;(2) During the hydrolysis reaction, the highest yield of the obtained product can reach 96% and the content of p-fluorobenzaldehyde can reach more than 99% when the hydrolysis temperature is controlled in a range of 110 ~120℃and n: n: n= 1∶1.6∶2.5. This method has many characteristics such as convenient raw materials, simple reaction conditions, stable process and high total reaction yield, and it has been used in industrial production.