ZnCl2催化尿素与苯酚合成氨基甲酸苯酯反应研究  

Synthesis of phenyl carbamate with urea and phenol catalyzed by ZnCl2

作　　者：仝甜 汪欣萍 王桂荣[1] 赵新强[1] 王延吉[1] TONG Tian;WANG Xin-ping;WANG Gui-rong;ZHAO Xin-qiang;WANG Yan-ji(School of Chemical Engineering,Hebei University of Technology,Tianjin 300130,China)

机构地区：[1]河北工业大学化工学院

出　　处：《高校化学工程学报》2020年第1期117-124,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(21236001);河北省自然科学基金(B2011202054)

摘　　要：采用催化剂筛选、正交实验、单因素实验、红外表征等实验手段,对尿素与苯酚合成氨基甲酸苯酯(PC)的反应性能及反应机理进行了研究。结果表明,在以ZnCl2为催化剂,n(尿素):n(苯酚)=1:36、催化剂用量为物料总质量的1%、反应温度150℃、反应时间9 h的较好反应条件下,PC收率可达64.25%。ZnCl2催化尿素与苯酚合成PC的反应机理为:尿素与ZnCl2首先形成新的配位配合物,即ZnCl2中Zn^2+与尿素羰基上的氧进行配位,使碳原子上的正电荷增多,进而碳原子被活化;然后苯酚中显负电的苯氧基作为亲核试剂进攻配合物中羰基碳原子,从而完成亲核取代反应生成目的产物PC。The reaction and mechanism of phenyl carbamate synthesis with urea and phenol were investigated by catalyst screening,orthogonal and single factor experiments and analyzed by Fourier transform infrared spectroscopy.The results show that yield of 64.25%can be obtained using ZnCl2 catalysts under conditions of molar ratio of urea/phenol=1/36,mass ratio of catalyst/total material=1%,reaction temperature of 150℃ and reaction time of 9 h.The reaction mechanism is as follows:a new complex forms from urea and ZnCl2 first,i.e.Zn2+coordinates with oxygen from carbonyl in urea,which leads to more positively charged carbon atom and the carbonyl group is activated.The negatively charged phenoxy group of phenol as a nucleophilic reagent attacks the carbon atom and the nucleophilic substitution reaction happens to produce the target product PC.

关 键 词：ZNCL2 尿素 苯酚 氨基甲酸苯酯 反应机理 

分 类 号：TQ243.2[化学工程—有机化工]