5Common DefinitionIonic Liquids (ILs) is the generic term for a class of materials, consisting entirely of ions and being liquid below 100°C.If they are liquid at room temperature, we call them room temperature ionic liquids (RTILs).
6Typical Cation and Anion Typical IL Cations* [PF6]- for moisture stable, water immiscible IL* [BF4]- for moisture stable, but water miscible IL* [AlCl4-] (or other Lewis acids) decomposes in water
7Discovery and History Paul Walden * The description of a low melting point saltEthyl ammonium nitrate* The first room temperature ionic liquidN-ethylpyridinium bromide- aluminium chloride melt* The most stable and conductive salts1,3-dialkylimidazolium salts* The hydrophobic ionic liquids1-ethyl-3-methylimidazolium tetrafluoroborate
2012 principles of Green Chemistry 1. Waste Prevention2. Atom Economy3. Less Hazardous Chemical Process4. Designing Safer Chemicals5. Safer Solvents and Auxiliaries6. Energy Efficiency7. Renewable Feedstocks8. Reduce Derivatives9. Catalysis10. Design for Degradation11. Real-time Analysis for Pollution Prevention12. Safer Chemistry for Accident Prevention
21Journal of Fluorine Chemistry A novel pyrrolidinium ionic liquid with 1,1,2,2 tetraﬂuoro 2 (1,1,2,2-tetraﬂuoroethoxy) ethanesulfonate anion as a recyclable reaction medium and efﬁcient catalyst for Friedel–Crafts alkylations of indoles with nitroalkenesJin-Hong Lin, Cheng-Pan Zhang, Zhi-Qiang Zhu, Qing-Yun Chen, Ji-Chang Xiao *
25Green AspectsThe yeild for preparing Ionic liquid is as high 99%. (Principle 2)Seperation of Ionic liquid is easy , just by filtration.Reaction condition is mild .(Principle 12)No byproducts in the preparation .(Principle 8)
26Green AspectsThe high concentration of highly acidic species that can be immobilized in ionic liquids and that leads to a highly reactive catalytic phase allowing for fast reactions under mild conditions. In fact, acidic ionic liquids catalyze all reactions that are conventionally catalyzed by AlCl3, but without suffering the disadvantage of the low solubility of AlCl3 in many solvents.(Principle #3,5,9)The liquid nature of the catalytic phase eliminates the heat and mass transfer problems frequently encountered with heterogeneous Friedel–Crafts-catalysts and make the reaction get high yield .(Principle 2)The miscibility gap of most ionic liquids with alkylated aromatics allows for product isolation by simple decantation.(Principle #1,7)
27Green AspectsIonic liquid also act as solvent in this reaction ,it prevents the waste of solvent.(Principle 1)Ionic liquid can be used directly for the next run after removing the solvent. Principle 7
28ConclusionIonic liquids ,as the new materials of multifunction , are widely used in various of fields.Environmently-friendly reaction process have vigorously been studied from the standpoint of green chemistry and based on the properities of easy separation , low toxicity , selective miscibility , ILS play an important role in organic synthesis as the green alternative solvent.Withe the development of multifunctional ILS , we can expect IlS would apply in more fields .