间二氟苯的合成研究

SYNTHESIS OF M-DIFLUOROBENZENE FROM M-DICHLOROBENZENE

提出了一种以间二氯苯为原料 ,经硝化、氟代、氯化和脱氯反应合成间二氟苯的新工艺路线 .探索了各步反应的工艺条件 ,对其中的关键步骤氟化反应 ,使用相转移催化剂取得较好的效果 ,反应收率可达6 8%左右 ;用离子交换法制备Pd/C催化剂 ,脱氯活性更高 .实验表明 ,该合成路线具有原料成本低 ,反应条件缓和 ,操作方便等优点 .

A method is given for synthesis of 1,3-difluorobenzene from 1,3-dichloro -benzene by nitration, fluorination, chlorination and dechlorination etc. The suitable technological conditions were investigated for each step. In order to increase the yield of fluorination which was the key step,phase transfer catalyst was used. The result showed that the yield of fluorination was about 68%. There is more activation of dechlorination. for the Pd/C catalysis manufactured by ion exchange method. As compared with other methods for preparing 1,3-difluorobenzene,there are many advantages with respect to low costs, mild conditions and easy operations for this synthesis route.