相转移催化合成3,4-二氟苯腈的研究  

Synthesis of 3,4-Difluorobenzonitrile by Phase Transfer Catalysis

作　　者：杨伟领 兰红丽 宋芬 施险峰 廖本仁 

机构地区：[1]上海华谊集团技术研究院,上海200241 [2]华东理工大学化学与分子工程学院,上海200237

出　　处：《化学世界》2015年第1期47-50,共4页Chemical World

摘　　要：以3,4-二氯苯腈为原料,采用相转移催化合成了3,4-二氟苯腈。考察了不同相转移催化剂、物质的量比、温度、水对反应的影响。结果表明,双-(N-双(二甲胺基)亚甲基)-氯化亚铵盐为最优催化剂,反应体系水含量控制在0.05%以下,在投料比为n(3,4-二氯苯腈)∶n(KF)∶n(催化剂)=1∶3∶0.1,140℃反应3h,190℃反应5h,3,4-二氯苯腈转化率为99%,产物3,4-二氟苯腈的收率为81%,纯度为99%。相比于先前的报道,本工艺使用新颖的N-烷基共轭季铵盐催化剂,采用分段升温法,明显降低了反应温度,缩短了反应时间,有效减少了脱卤、聚合、焦化等副反应的产生,进一步提高了3,4-二氟苯腈的收率。3,4-Difluorobenzonitrile was synthesized by using 3,4-dichlorobenzonitrile as the starting material via phase transfer catalysis.The influencing factors of the reaction such as mole ratio,reaction temperature,reaction time,catalyst,potassium fluoride and amount of water were investigated.The optimal reaction conditions were obtained.The results showed that bis（N-bis（dimethylamino）methylene）-iminium chloride was the optimal catalyst,and the reaction was conducted at the ratio of n（3,4-dichlorobenzonitrile）∶n（potassium fluoride）∶n（catalyst）=1∶3∶0.1while maintaining the water content in the reaction system below 0.05%.After reacting for 3hat 140℃and 5hat 190℃,the conversion rate of 3,4-dichlorobenzonitrile was 99%,and the yield of 3,4-difluorobenzonitrile was 81%.Compared with previous reports,this new approach used step reaction method with a novel N-alkyl-conjugated ionic quaternary ammonium salt catalyst.It could significantly reduce the reaction temperature,shorten the reaction time and improve the reaction selectivity and yield.

关 键 词：3 4-二氯苯腈 3 4-二氟苯腈 相转移催化 氟化钾 

分 类 号：TQ242[化学工程—有机化工]