硫酸氢钠催化下甲苯的硝化

Nitration of Toluene in the Presence of Sodium Bisulfate Catalyst

研究了硫酸氢钠催化下甲苯用硝酸的硝化。结果表明,在醋酐存在条件下,以CCl4为溶剂,以质量分数为95%的硝酸为硝化剂,反应温度控制在45℃,反应进行60min,选用硫酸氢钠催化剂,对甲苯表现出了强的区域选择性,甲苯硝化产物邻对位比达1.09,较硝酸硫酸混酸的1.67显著降低,硝化产物收率达到99.9%。催化剂可循环使用5次,催化活性基本不变,是一种极具工业化开发价值的硝化反应催化剂。

Mononitration of toluene with nitric acid in the presence of sodium bisulfate was studied. The results show that when the nitrated reaction temperature was controlled at 45 ℃, and the nitrated reaction time was 60 min, nitration of toluene with 95% nitric acid as nitrating reagent in the presence of acetic anhydride and 1.8 g sodium bisulfate catalyst exhibited a high regioselectivity, with ortho-para isomer ratio up to 1.09 in product distribution of toluene nitration, greatly below ortho-para isomer ratio of 1.67 in the product distribution of toluene nitration with sulfonitric acid as catalyst, and gave a yield of 99. 9%. The catalyst could be reutilized up to five times with little decrease in activity. It is a kind of prowising nitrated reaction catalyst to replace sulfonitric acid, and has a vast value of industrialization exploitation.