摘要
常温下,采用三光气与均苯三甲酸在催化剂作用下制备均苯三甲酰氯(TMC),最佳收率可达88%.产品熔点为32.5～33.6 ℃,w(TMC)>99.2%,IR图谱与标准谱基本一致.通过对催化剂、溶剂和反应底物配比等影响因素的研究发现:(1)在常温下单一催化剂,如N,N-二甲基甲酰胺、吡啶、咪唑、三乙胺等不能让反应进行完全,收率＜32%;而用复合催化剂,如吡啶/N,N-二甲基甲酰胺、咪唑/三乙胺等在常温下能反应完全,收率＞60%.(2)溶剂的溶度参数与均苯三甲酰氯的溶度参数相差越小,反应速度越快.(3)反应底物配比n(三光气)/n(均苯三甲酸)<1.2时,几乎得不到产品,随着n(三光气)/n(均苯三甲酸)增大,收率增高;当n(三光气)/n(均苯三甲酸)＞3后,其增大对产品收率影响不大.
Trimesoyl chloride（TMC） was prepared from trimesic acid（TMA） using triphosgene at room temperature. The best result was that trimesic acid reacted with triphosgene at room temperature in the presence of imidazole/DMF using tetrahydrofuran as solvent to give TMC in 88% yield. Purity of the product was more than 99.2%, and its melting point was 32.5～33.6℃. Effects of catalyst and solvent on the reaction were discussed. In the presence of single catalyst, such as dimethylformamide （DMF） , pyridine, imidazole and triethylamine, the yields were all below 32% ,while in the presence of binary catalyst,such as pyridine/DMF and imidazole/DMF, the yields were higer than 60%. Speed of the reaction depended on the solvent to some extent because it is good for the heterogeneous reaction mixture to dissolve the product （TMC） into the solvent quickly; it spent less time to become homogeneous if the solubility parameter of solvent was close to that of TMC. The mole ratio n （BTC）/n（TMA） was an important factor in the reaction. The yield was nearly zero if n（ BTC）/n（TMA） 〈 1.2, and increased with the increase of the mole ratio until n （BTC）/n （TMA） 〉3.
出处
《精细化工》
EI
CAS
CSCD
北大核心
2005年第8期628-630,共3页
Fine Chemicals
基金
"863"高技术研究发展计划(No.2002AA328010)
国家"973"计划资助项目(No.2003CB615700)~~
