The Study On The Applications Of Room Temperature Ionic Liquids In Selective Organic Reaction

This dissertation consists of three parts. The first part, we reviewed the application of ionic liquids in selective organic reaction and promoting organic reaction. In part two, we studied the ionic liquids-promoted selective organic reaction, the selective bromonation of activated aromatic compounds using ionic liquid [Bmim]Br₃. In part three, we reported the experimental procedure and spectroscopic data etc.In the first chapter of part two, first, we studied the selective N-alkylation of benzotriazole with a variety of halogen using base or in absent of base in ionic liquid [Bmim][BF₄], [Bmim][PF₆]. This method not only improved yields and selectivity, but also the ionic liquids can be recovered and reused with no appreciable decrease in yield. Second, we completed the selective N-alkylation and electrophilic addition of pyrrole ionic liquids [Bmim][BF₄], [Bmim][PF₆]. The present method has many obvious advantages, which provides a simple and efficient method for the synthesis of the N-substituted pyrroles. Third, we studied the N-alkylation of phthalimide, indole, benzimidazole, succinimide with a variety of halogen in ionic liquid [Bmim][BF4], [Bmim][PF₆]. The present method has many obvious advantages, compared to those reported in the literature, including the generality, simplicity of the methodology, the ease of product isolation, the higher yield and potential for recycling of ionic liquids. Fourth, we completed the condensation of succinic anhydride, maleic anhydride and phthalic anhydride with aromatic amines and alphatic amines without an added base in ionic liquids [Bmim][BF4], [Bmim][PF6]. This method decreased reaction temperature, improved yields. Fifth, we reported the three- component condensation of benzotriazole with aldehyde and alcohol in ionic liquids [Bmim][BF₄], [Bmim][PF₆] and [BuPy]BF₄. The present method has many obvious advantages compared to the conventional method, including rate acceleration, environmentally more benign, the simplicity of isolation of the product, higher yield, and possibility of recycling of the ionic liquid.In the second chapter of part two, we reported the regioselective mono-bromination of arylamines, phenols and several activated aromatic compounds with under solvent-free conditions using a new reagent [Bmim]Br3, demonstrated regioselective monobromination of arylamines, phenols and several activated aromatic cimpounds with [Bmim]Br3 can efficiently be performed under solvent-free conditions, which will be a highly useful method because of its ease, simplicity, high selectivity, excellent yield of product, and environmentally more benign. The ionic liquid plays the dual role of solvent and promoter.In summary, the above alkylation, condensation reactions, selective reaction and the synthetic methods possess such advantages as readily available starting materials, mild reaction conditions, simple operation, high selectivity, high yields, environmentally benign and the potential for recycling of ionic liquids.