摘要
以四氯苯酐为原料,经酰亚胺化,氟化,水解,脱羧四步反应合成四氟苯甲酸。研究了相转移催化剂对酰胺化反应、氟化反应的影响。结果表明,酰亚胺化反应中通过使用分水器,控制溶剂用量,同时使用相转移催化剂,缩短了反应时间,收率达98.8%。氟化反应中采用冠醚做催化剂,喷雾干燥氟化钾做氟化剂,收率达到91.4%。经过改进,反应总时间由56h缩短至11h,反应总收率由47.3%提高到70.7%。
2,3,4,5-Tetrafluoro-benzoic acid was synthesized from tetrachlorophthalic anhydride via im- idation, fluorination, hydrolysis and decarboxylation. The influences of phase transfer catalyst on imi- dation and fluorination were studied. Experimental results show that imidation reaction time decreased when water separator and phase transfer catalyst were used, and solvent consumption was controlled; the imidation yield was 98. 8%. The yield reached 91. 4% when crown ether was chosen as phase transfer catalyst, and spray dried potassium fluoride was used as fluorinating agent. Compared with the literature method, the overall reaction time of the improved method decreased from 56 h to 11 h, and the total yield increased from 47.3% to 70.7%.
出处
《精细石油化工》
CAS
CSCD
北大核心
2012年第3期52-54,共3页
Speciality Petrochemicals
关键词
四氯苯酐
酰亚胺化
氟化
水解
脱羧
2,3,4,5-tetrafluoro-benzoic acid
imidation
fluorination~ hydrolysis
decarboxylation
