Synthesis And Application Of Task-Specific Ionic Liquids In Pharmaceutical Synthesis

As novel green solvent, ionic liquids were widely used in kinds of organic synthesis reactions because of their excellent physical-chemical properties. The changed reaction mechanism and improved activity and stability of catalyst and high yield were always found in task-specific ionic liquid, which was a bursting branch of ionic liquid. Ionic liquid anchored catalysts cherished many advantages such as ease of isolation from reactants or products and catalyst recycle, excellent mechanical performance and high stability, improved catalyst activity and selectivity in homogeneous catalytic system.Amide task-specific ionic liquids were synthesized by three steps. The first step was classical organic synthesis reaction. The conditions of second and third step were optimized by orthogonal experiments. The quatemary ammonium salts were synthesized under the conditions of the mole ratio of alkyl imidazolium and 2-chloroacetamides of 1∶1, reaction solvent of toluene, reaction time of 12.0 hours. The amide task-specific ionic liquids were synthesized under the conditions of the mole ratio of quaternary ammonium and sodium tetrefluoroborate (potassium hexafluoro phosphate) of 1∶1.1, reaction solvent of acetone, reaction time of 24.0 hours. A series of amide-task-specific ionic liquids were synthesized under the above optimum conditions. The structure of the amide-task-specific ionic liquids is characterized by IR and 1^HNMR. The properties were tested and the results showed that they were easily soluble in high polarity solvents, partly soluble or immiscible in moderate or weak polarity solvents; they have excellent thermal stability (The TG-DTA analysis results showed that the thermo steady of they are up to 300℃) and electrochemical performance (The electrochemical windows is 3.5V). The CuCl₂-task-specific ionic liquids were synthesized. The reaction conditions were optimized by single factor experiments. The reaction conditions were including that the reaction solvent is n-hexane, the reaction temperature is reflux temperature, and the reaction time is 4.0 hours. The structure was characterized by IR and 1^HNMR.The application of task-specific ionic liquids in the synthesis of 2, 3-cyclopenteno-pyridrine has been studied. The reaction conditions were established by single factor experiments. The reaction conditions were including that the suitable solvent and catalyst are BMImBF₄ and BMImCl-CuCl₂, the addition of catalyst is 10%, the reaction mole ratio of cyclopentanone and propargylamine is 1∶1.5, the reaction temperature is 60℃, the reaction time is 3.0 hours. The 2, 3-cyclopentenopyridine is obtained in yield of 68% under above optimum reaction conditions. The ionic liquid anchored CuCl₂ is easily to be recycled at least three times with a slightly activity loss. Compared with literature method, the manifest advantages which include short reaction times, high selectivity and yield, simple process, ease of recycle of ionic liquid anchored catalyst had been observed in the novel method.