负载型硫酸催化合成二苯甲烷二氨基甲酸甲酯  

Synthesis of 4,4'-Methylene Diphenyl Dimethylcarbamate Catalyzed by Silica-Supported Sulfuric Acid

作　　者：王晶[1] 耿艳楼[1] 赵新强[1] 郭莲[1] 安华良[1] 王延吉[1] 

机构地区：[1]绿色化工与高效节能河北省重点实验室河北工业大学化工学院,天津300130

出　　处：《石油化工》2009年第1期82-85,共4页Petrochemical Technology

基　　金：国家自然科学基金资助项目(20576025);河北省自然科学基金资助项目(B2007000010);河北省科学技术研究与发展计划项目(07215602D)

摘　　要：制备了SiO2负载硫酸催化剂,并将其用于催化苯氨基甲酸甲酯(MPC)与甲醛进行缩合反应合成二苯甲烷二氨基甲酸甲酯(4,4′-MDC)。以碳酸二甲酯(DMC)为溶剂,考察了反应时间、反应温度、原料配比、催化剂用量、溶剂用量等因素对该缩合反应的影响。得到的适宜反应条件为:催化剂的酸量与甲醛的摩尔比为1.3、MPC与甲醛的摩尔比为4、DMC与MPC的质量比为8、反应温度80℃、反应时间3h。在此条件下,4,4′-MDC的收率为56.0%,选择性为75.0%。在催化剂循环使用过程中,催化剂初次使用后,活性有所降低,但选择性提高;此后其催化活性和选择性稳定,循环使用4次基本保持不变。Silica-supported sulfuric acid was prepared and used as catalyst in synthesis of 4,4＇- methylene diphenyl dimethylcarbamate （ 4,4＇-MDC ） from methyl N-phenyl carbamate （ MPC ） and formaldehyde with dimethyl carbonate （DMC） as solvent. The influences of reaction time, reaction temperature, mole ratio of MPC to formaldehyde, dosage of silica-supported sulfuric acid catalyst and amount of solvent on 4,4＇-MDC synthesis were studied. Under optimal reaction conditions： 80℃, mole ratio of MPC to formaldehyde 4, mole ratio of H ^＋ of catalyst to formaldehyde 1.3, mass ratio of DMC to MPC 8 and reaction time 3 h, yield and selectivity to 4,4＇-MDC are 56.0% and 75.0%, respectively. The preparation of silica-supported sulfuric acid catalyst is simple. The H^＋ amount on catalyst is determined by titration. Although after first run catalytic activity of silica-supported sulfuric acid catalyst decreases and selectivity increases, there is no significant loss in both catalytic activity and selectivity in the following four cycles of runs.

关 键 词：二氧化硅负载硫酸催化剂 苯氨基甲酸甲酯 二苯甲烷二氨基甲酸甲酯 甲醛 缩合反应 

分 类 号：TQ203.2[化学工程—有机化工]