季铵盐相转移催化合成对硝基苯甲醚工艺研究

STUDY ON SYNTHESIS OF p-NITROANISOLE USING QUATERNARY AMMONIUM SALTS AS PHASE TRANSFER CATALYST

在氢氧化钠碱性介质中 ,以氯化苄基三乙基铵 (TEBA)为相转移催化剂 ,由对硝基氯苯 (PCNB)和甲醇(CH3OH)反应合成了对硝基苯甲醚 (PNA) ,研究了催化剂用量、催化剂结构、碱用量等对反应的影响 ,确立的适宜的反应条件为 :n(PCNB)∶ n(CH3OH)∶n(Na OH)∶ n(TEBA) =1∶ 3∶ 3∶ 0 .0 2 5～ 0 .0 5 ,反应温度约 80℃ ,反应时间约 7～ 8h。该条件下 ,相转移催化反应为假一级反应 ,反应的活化能约为 74.1 k J/mol。产品 PNA收率大于 95 % (按对氯硝基苯计算 ) ,经气相色谱分析 ,产品纯度为 99.7%。

In the presence of sodium hydroxide, p nitroanisole was obtained using triethyl benzyl ammonium chloride (TEBA) as phase transfer catalyst by reaction of p chloronitrobenzene (PCNB) and methanol. Effects of amounts of catalyst and its structure, amounts of base and its concentration and so on to the reaction were studied. The optimum reaction conditions were determined, that is, n (PCNB)∶ n (CH 3OH)∶ n (NaOH)∶ n (TEBA)=1∶3∶3∶0.0250.05, the reaction temperature is about 80 ℃, reaction time is about 78 h. Under these conditions, the phase transfer catalysis reaction is a pseudo first order reaction, and the reaction activation energy is about 74.1 kJ/mol. The yield of p nitroanisole based on p chloronitrobenzene is over 95%, the purity of the products is about 99.7% by GC analysis.