摘要
室温下以分子筛固载氟化钾为催化剂催化芳香醛和丙二腈(或氰乙酸乙酯)的Knoevenagel缩合反应,合成了一系列的不饱和产物。考察了原料和催化剂的用量对产率的影响,利用薄板层析(TLC)确定反应时间。最佳合成条件是芳醛和丙二腈(或氰乙酸乙酯)的物质的量比为5∶5.5,催化剂用量为0.30g,室温反应45～300min,产率可达87%～99%。该反应具有操作和后处理方便、产率高、污染少等优点。另外,催化剂通过简单的处理即可循环使用,为该化合物的制备提供了简便易行的方法,既可强化学生的环保意识,又可使学生掌握绿色化学的实用技术。
KF supported on molecular sieve is used as the catalyst for the Knoevenagel condensation reaction of aromatic aldehydes with malononitrile or ethyl cyanoacetate at room temperature . A series of unsaturated products are synthesized .Effects of the amount of raw materials and the catalyst loadings on the yields are investigated ,and the reaction times are determined by thin layer chromatography （TLC ） . The optimum reaction conditions are as follows ：the molar ratio of aromatic aldehydes to malononitrile or ethyl cyanoacetate is 5∶5 .5 ,the amount of the catalyst is 0 .3 g and the reaction time at room temperature is 45-300 min .The yield of products reaches 81~93% .This method possesses the advantages of simple operation and work-up procedure ,good yields and less pollution .The catalyst can be recycled by simple treatment .This reaction provides a simple and easy method for the preparation of the compounds .Using this method ,students can raise their consciousness of environmental protection and master practical teaching techniques of green-chemistry .
出处
《实验技术与管理》
CAS
北大核心
2014年第7期39-42,共4页
Experimental Technology and Management
基金
国家自然科学基金资助项目(21272167)
