采用L18(36×61)正交实验,考察了反应温度、氢氧化钠溶液浓度、油水体积比、十二烷基苯磺酸钠用量、Pd(PPh3)2Cl2用量、PPh3用量、溶剂(叔丁醇、正丁醇、正庚烷)等因素对氯化苄单羰基化合成苯乙酸的影响,得出其较佳反应条件为以正丁醇为反应溶剂,不加表面活性剂,加0.24 g PPh3、0.4g Pd(PPh3)2Cl2、20 mL氯化苄、55 mL正丁醇、75 mL 3.5 mol/L的NaOH水溶液,在50℃下反应3 h,此时苯乙酸的产率可达99.0%;另外,还探讨了反应体系中空气与苯乙酸的引入对反应的影响,结果表明:反应体系中空气的存在以及循环油相反应液中苯乙酸的带入对反应的速率、催化剂的稳定性及性能、苯乙酸的产率影响很大.%The influences of the factors affecting the synthesis of phenylacetic acid in the carbonylation of benzyl chloride are studied by means of an orthogonal experiment[L18(36×61)] in this article. These factors include reaction temperature, the concentration of sodium hydrate liquor, the ratio of organic phase volume to aqueous phase volume (Vo:Vw), the amount of sodium dodecyl benzene sulfonate, the amount of Pd(PPh3)2Cl2 and PPh3, the solvent(primarily tert-butyl alcohol, n-butyl alcohol, n-heptane) etc. The optimum reaction conditions have been concluded: n-butyl alcohol was used as the solvent, with one-time pour of 0.24g PPh3, 0.4g Pd(PPh3)2Cl2, 20 mL benzyl chloride, 55 mL n-butyl alcohol and 75 mL sodium hydrate liquor of 3.5 mol/L but no surfactant, and the reaction was carried out at 50℃for 3 hours. The so-obtained yield of phenylacetic acid can be up to 99%. In addition, the influences of the presence of phenylacetic acid and air in the reaction system are also studied. The result shows that the presence of air in the system and the entrainment of phenylacetic acid in the circulating organic phase have great influence on reaction rate, the stability and performance of catalyst and the yield of phenylacetic acid.
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