摘要
制备了一系列磺酸吡啶功能化酸性离子液体(ILs),采用Hammett指示剂与紫外联用法测定了其酸强度。考察了各酸性离子液体在苯氨基甲酸甲酯(MPC)与甲醛缩合制备二苯甲烷二氨基甲酸甲酯(MDC)反应中的催化活性。结果表明,离子液体的酸强度与其催化活性关联较好;[HSO3-bpy]CF3SO3酸强度最高,催化活性也最好。以[HSO3-bpy]CF3SO3为催化剂兼溶剂,优化了MDC合成反应条件。在反应温度70℃,反应时间60min,MPC与甲醛的摩尔比为12,离子液体与MPC的质量比为4的条件下,MDC产率最高可达91·5%。用水处理反应液,通过减压蒸馏后的离子液体可以循环使用5次以上。
A series of sulfonic acid-functional ionic liquids (ILs) were prepared and their acid strength was determined by the Hammett method combined with UV-visible spectroscopy. Then the catalytic activity of the ILs for the synthesis of methylene diphenyl dimethylcarbamate (MDC) from methyl phenyl carbamate (MPC) and formaldehyde (HCHO) was evaluated. The result showed that the acid strength of the ILs was well consistent with their catalytic activity. The acidity of [HSO3-bpy] CF3SO3 was the strongest and its catalytic activity was the highest. The reaction conditions for the synthesis of MDC were optimized using [HSO3-bpy] CF3SO3 as reaction media. Under the suitable reaction conditions of 70℃, 60 rain, molar ratio of MPC to HCHO 12 and mass ratio of ILs to MPC 4, the yield of MDC was 91.5%. [HSO3-bpy]CF3 SO2 could be reused more than five times after the removal of water by vacuum distillation.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2008年第4期887-891,共5页
CIESC Journal
基金
国家自然科学基金项目(20576025)
河北省自然科学基金项目(B2007000010)
河北省科学技术研究与发展计划项目(07215602D)~~
关键词
磺酸吡啶酸性离子液体
苯氨基甲酸甲酯
甲醛
二苯甲烷二氨基甲酸甲酯
sulfonic acid-functional ionic liquid
methyl N-phenyl carbamate
formaldehyde
methylene diphenyl dimethylcarbamate
作者简介
王娜(1983-),女,硕士研究生。
联系人:赵新强。