Comparison of the efficiency of two imidazole-based dicationic ionic liquids as the catalysts in the synthesis of pyran derivatives and Knoevenagel condensations
作者:Zahra Sharifi、Nader Daneshvar、Mohaddeseh Safarpoor Nikoo Langarudi、Farhad Shirini
DOI:10.1007/s11164-019-03874-5
日期:2019.10
([C4(MIm)2]·2HSO4) were prepared via adequate, solvent-free methods and characterized using FT-IR, 1H NMR, 13C NMR, and potentiometric titration techniques. These reagents were investigated in the synthesis of 5-arylidene (thio)barbituric acids, 2-arylidene malononitriles, 4H-pyrans, and pyrano[2,3-d] pyrimidineones, and their catalytic activities were compared in the promotion of these reactions. Based
在目前的工作中,使用3,3'-(1-丁烷1,4-丁二)双(1-甲基-1 H-咪唑-3-鎓)二氯化物([C 4(MIm)2 ]·2Cl)和3,通过适当的,无溶剂的方法制备了3 ' -(丁烷-1,4-二基)双(1-甲基-1 H-咪唑-3-鎓)硫酸氢盐[[C 4(MIm)2 ]·2HSO 4) FT-IR,1 H NMR,13 C NMR和电位滴定技术进行表征。在合成5-芳基(硫代)巴比妥酸,2-芳基丙二腈,4 H-吡喃和吡喃并[2,3- d]时对这些试剂进行了研究。比较嘧啶酮及其催化活性,以促进这些反应。根据获得的结果,我们发现[C 4(MIm)2 ]·2Cl在需要碱性或弱酸性介质的情况下显示出更高的催化效率。相反,在需要酸性催化剂以提高反应速率的反应中,[C 4(MIm)2 ]·2HSO 4是强大的催化剂。使用这些试剂,可以在较短的反应时间内,在温和,环保的条件下以优异的收率形成产物,而无需使用柱色谱进行后处理。