文献类型：专利

英文题名：Preparation of 2,3,4,5-tetrafluorobenzoic acid - using 3,4,5,6-tetrachlorophthalic acid anyhdride and aniline as raw materials

作者：CHEN W;SONG G;QIAN X

机构：[1]UNIV EAST CHINA SCI & TECHNOLOGY

申请号：CN1201779-A

申请日：1998-07-09

公开日：1998-12-16

语种：英文

收录：DERWENT

摘要：A process for preparing 2,3,4,5-tetrafluorobenzoic acid with 3,4,5,6-tetrachlorophthalic acid anhydride and aniline as raw materials comprises: condensation, fluorination, opening loop, removing carboxyl and hydrolysis. The fluorination and carboxyl-removing reactions take place at a lower temperature because aniline is used, resulting in existence of benzene cycle, and the carboxyl-removing step takes place at ordinary pressure as a non-protonic polar solvent is used, resulting in high purity of the product.