论文部分内容阅读
以2-溴-4-叔丁基苯酚、甲苯为原料,经叔丁基转移反应合成重要的有机中间体2-溴苯酚。该文考察了催化剂的种类、用量及反应条件对叔丁基转移反应的影响,结果表明:三氯化铝及其与叔胺盐酸盐的复合盐对叔丁基转移反应具有较好的催化活性。27Al NMR的分析表明:催化活性中心可能是三氯化铝与水解产生的氯化氢反应后形成的氯铝酸。进一步研究表明:氯化氢及溴化氢可提高三氯化铝的催化活性,降低三氯化铝的用量。优化后的工艺条件为:在二氯甲烷溶剂中,4-叔丁基苯酚与Br2在0℃反应,选择性形成2-溴-4-叔丁基苯酚,体系中n(2-溴-4-叔丁基苯酚)∶n(催化剂)∶n(甲苯)=1∶0.3∶6,于30℃“一锅法”反应制备了2-溴苯酚,其中,2-溴-4-叔丁基苯酚反应的转化率可达96.5%、2-溴苯酚的选择性达99.6%。
Using 2-bromo-4-tert-butylphenol and toluene as raw materials, 2-bromophenol, an important organic intermediate, was synthesized via t-butyl transfer reaction. The effects of catalyst type, amount and reaction conditions on the reaction of tert-butyl transfer were investigated. The results showed that aluminum trichloride and its complex salt with tertiary amine hydrochloride had a good catalytic activity for tert-butyl transfer active. 27 Al NMR analysis shows that the catalytic activity center may be formed by the reaction of aluminum chloride and hydrogen chloride generated after hydrolysis of chloroaluminate. Further studies show that: hydrogen chloride and hydrogen bromide can improve the catalytic activity of aluminum trichloride, reduce the amount of aluminum trichloride. The optimized conditions are as follows: 4-tert-Butylphenol reacted with Br2 at 0 ℃ in dichloromethane solvent to form 2-bromo-4-tert-butylphenol selectively, n 2-Bromo-4-tert-Butylphenol: n (Toluene) = 1: 0.3: 6 at 30 ° C for one- The conversion of butylphenol was 96.5% and the selectivity of 2-bromophenol was 99.6%.