Silica-Grafted Ionic Liquids as Recyclable Catalysts for the Synthesis of 3,4-Dihydropyrano[c]chromenes and Pyra-no[2,3-c]pyrazoles  

作　　者：Khodabakhsh Niknam Abolhassan Piran 

机构地区：[1]Department of Chemistry, Faculty of Sciences, Persian Gulf University, Bushehr, Iran

出　　处：《Green and Sustainable Chemistry》2013年第2期1-8,共8页绿色与可持续化学（英文）

摘　　要：Silica-grafted N-propyl-imidazolium hydrogen sulfate ([Sipim]HSO4) is employed as a recyclable heterogeneous ionic liquid catalyst for the synthesis of 3,4-dihydropyrano[c]-chromenes by the reaction of aromatic aldehydes, malononitrile and 4-hydroxycoumarin at 100°C under solvent-free conditions. Also, heterogeneous ionic liquid catalyst was used for the synthesis of pyrano[2,3-c]-pyrazoles by the reaction of aromatic aldehydes, malononitrile and 3-methyl-l-phenyl-5-pyrazolone at 110°C under solvent-free conditions. The heterogeneous ionic liquid showed much the same efficiency when used in consecutive reaction runs.Silica-grafted N-propyl-imidazolium hydrogen sulfate ([Sipim]HSO4) is employed as a recyclable heterogeneous ionic liquid catalyst for the synthesis of 3,4-dihydropyrano[c]-chromenes by the reaction of aromatic aldehydes, malononitrile and 4-hydroxycoumarin at 100°C under solvent-free conditions. Also, heterogeneous ionic liquid catalyst was used for the synthesis of pyrano[2,3-c]-pyrazoles by the reaction of aromatic aldehydes, malononitrile and 3-methyl-l-phenyl-5-pyrazolone at 110°C under solvent-free conditions. The heterogeneous ionic liquid showed much the same efficiency when used in consecutive reaction runs.

关 键 词：Silica-Grafted N-Propyl-Imidazolium Hydrogen Sulfate Aldehydes Pyrano[2 3-c]-Pyrazoles 3 4-Dihydropyrano[c]-Chromenes Solvent-Free Heterogeneous Ionic Liquid Catalysts 

分 类 号：O6[理学—化学]