Study On The Preparation Of Several Crown Ether Complex Metal Cation Ionic Liquidand Their Applications In Organic Reactions

In the past decades, the room temperature ionic liquids (RTILs) had been an explosion of development. The unique composition of ionic liquids led to the special characteristics that were negligible vapour pressure, high ionic conductivity, substitute for organic solvents, catalytic organic reactions and so on. Based on the our group previous work, five kinds of Lewis acidic ionic liquids composed of crown ether complex cations were designed and applied in organic reaction. In addition, a series of rare based crown ether complex cation ionic liquids were used in multicomponent reactions. This artical was consisted of four parts:Chapter 1:In this paper, the properties of ionic liquids and theirs applications in many fields were reviewed.Chapter 2:A series of Lewis acidic ionic liquids composed of crown ether complex cations, were designed, synthesised and characterised by Raman, MS, FT-IR, thermogravimetric differential thermal analysis (TG-DTA) and elemental analysis.Chapter 3:These Lewis acidic ionic liquids were utilized as catalysts to prepare benzimidazole and 1-benzyl-2-phenyl-1H-benzo[d]imidazole, with the different reaction conditions and experimental procedure, we could get the different selectivity target product. In addition, the ionic liquids were best catalyst in Friedel-Crafts alkylation reaction under mild conditions.Chapter 4:Five crown ether complex cation ionic liquids [18-C-6K][X] (X= PO4, HPO4, H2PO4, OAc, CO3) were applied as high efficient catalysts to Knoevenagel condensation and revealed excellent performances in three-component reactions of aldehydes and active hydrogen compounds to 4H-pyran derivatives in excellent yields. All reactions were taken place under extremely mild condition within several minutes and easy to handle. Moreover, the catalyst of ionic liquid [18-C-6K]3[PO4] can be recovered and reused six times without loss of activity.