The Synthesis And Applications Of Crown Ether Complex Metal Cation Ionic Liquids

As new media and soft functional materials developed under the concept of green chemistry, ionic liquids have many advantages such as good thermal stability, not volatile, solubility adjustable, structure adjustable, recyclable, good solubility and stability of organic compounds and inorganic compounds, can be used as solvents and catalysts in a variety of organic reactions. The design, synthesis and development of new ionic liquids are of the most important in green chemistry. We have successfully chelated crown ethers and organic or inorganic metal salt, alkali compound and gained series of salts with melting points less than200℃, defined as the " Crown Ether Complex Cation Ionic Liquid"(CEIL).In this thesis, we have studied the applications of crown ether complex cation ionic liquids in organic reactions in the following areas:Chapter1:An overview of the classification, nature, history, synthetic methods of the ionic liquids, and its applications in organic synthesis, cellulose and other areas.Chapter2:Design and synthesize a series of new ionic liquids-crown ether complex cation Ionic liquids. We synthesized17kinds of non-chiral crown ether complex cation ionic liquids using crown ethers and alkali metal salts or alkali, and28kinds of chiral crown ether complex cation ionic liquids using crown ether, NaOH or KOH and natural amino acids in the aqueous solution. The melting points of the crown ether complex cation compounds are less than200℃, and we define them as the "crown ether complex cation ionic liquids". In addition, we also used the aza-crown ether instead of the crown ether to prepare8kinds of aza-crown ether complex cation ionic liquids. Chapter3:The applications of CEIL [15-C-5Na][OH] in Michael addition reaction. We have used the alkaline ionic liquid [15-C-5Na][OH] efficiently catalyzed23teams of Michael addition reactions. Most of the reactions can be achieved with relatively high yields (>80%) in a short time (within30min) under room temperature.[15-C-5Na][OH] can be used as both catalyst and solvent, and showed significant solvent effect in the reaction. The ionic liquid can be recycled five times without lost of activity.Chapter4:The application of CEIL [18-C-6K][OH] in Henry reaction. Alkaline ionic liquid of [18-C-6K][OH] showed high catalytic activities in the reactions of aldehydes and nitromethane at room temperature. From the study of Henry reactions of20kinds of aldehydes with nitromethane, we found that the reactions of aromatic aldehydes could be occured efficiently at room temperature, but aliphatic aldehydes must be reacted at low temperatures (-15℃) to obtain target products due to its high activities. In these reactions the catalyst can be recycled.[18-C-6K][OH] reused five times without obvious lost of catalytic activity in the reaction of2-nitrobenzaldehyde and nitromethane.[18-C-6K][OH] also showed high catalytic activities in Knoevenagel condensations of aromatic aldehydes and malononitrile.Chapter5:The applications of CEILs [18-C-6K]3[PO4],[18-C-6K]2[HPO4],[18-C-6K][H2PO4] in Heck reaction.[18-C-6K]3[PO4]/PdCl2/K2CO3,[18-C-6K]2[HPO4]/PdCl2/K2CO3and [18-C-6K][H2PO4]/PdCl2/K2CO3catalyst systems showed high activities in the Heck reactions of aromatic halides and alkenes. Among these catalytic systems,[18-C-6K]3[PO4]/PdCl2/K2CO3have the best catalytic activity. Using this system, we carried out22groups of Heck reactions in N, N-dimethyl formamide (DMF), most of which gained high yields in a short time. It can be seen from the results that a synergistic effect existed between [18-C-6K]3[PO4] and DMF, which promoted the occurrence of the reaction. And the catalytic system is non-sensitive to water and oxygen.Chapter6:The applications of chiral CEILs in the asymmetric cycloaddition reactions of CO2and epoxides. The chiral CEILs as cocatalyst and chiral SalenCo (Ⅲ) as catalyst formed new chiral catalyst systems, which can catalyze the asymmetric cycloaddition reactions of CO2and epoxides efficiently. The synergistic effect between chiral amino acid anions and chiral SalenCo (Ⅲ) increased the ee values of products.Chapter7:The applications of aza-crown ether complex cation ionic liquids in organic reactions. Aza-crown ether complex cation ionic liquids can be used alone as catalysts in the coupling reaction of CO2and epoxides. In addition, the aza-crown ether complex cation ionic liquids also can catalyze the reactions of propylene carbonate and aniline compounds which produce important intermediates in organic synthesis and pharmaceutical precursors.