Ionic Liquids
Chapter 1: Introduction
Chapter 1: Introduction Ionic liquids (ILs) can be viewed as a new and remarkable class of solvent. They are also a type of materials that have a long and useful history, where the earliest material that meets the current definition of IL was observed in the mid-19th century when a separate liquid phase called the “red oil” was observed in Friedel-Crafts reaction [17]. Over the following years, there has been a rapid growing of interest in ILs due to the realization that these materials may have greater utility as reaction solvent, although they were formerly used for specialized electrochemical applications. Unlike the more volatile organic solvents, ILs are non-volatile, non-flammable and thermally stable. The physiochemical properties of the ILs can be altered by changing the anion and cation combination. These not only offer new opportunities on how to perform known reactions, but the ILs can even be tailored to meet specific synthetic needs. One notable application of IL is the salt ability to act as solvent in many organic reactions is known to accelerate product formation or alter the selectivity of the reaction. For example, in the Diels-Alder reaction, where higher reaction rate and selectivity are obtained in polar solvents compared to non-polar solvents [17]. However, the vast applications of ILs are not without problems, one being that yields, purity and selectivity can vary according to the batch of ionic liquid used and the methods used to synthesis and purify the ILs. Therefore it is of great interest to study methods on how to minimize this problem.
The Objective of Research.
The objective of this research is to synthesize and characterize eight ionic liquids using 1-methylimidazole as the starting material by using the alkylation and metathesis synthesis methods. H1-NMR and Ion Chromatography (IC) analysis will be used to verify the characteristic and presence of impurities to determine the purity of
Chapter 1: Introduction Ionic liquids (ILs) can be viewed as a new and remarkable class of solvent. They are also a type of materials that have a long and useful history, where the earliest material that meets the current definition of IL was observed in the mid-19th century when a separate liquid phase called the “red oil” was observed in Friedel-Crafts reaction [17]. Over the following years, there has been a rapid growing of interest in ILs due to the realization that these materials may have greater utility as reaction solvent, although they were formerly used for specialized electrochemical applications. Unlike the more volatile organic solvents, ILs are non-volatile, non-flammable and thermally stable. The physiochemical properties of the ILs can be altered by changing the anion and cation combination. These not only offer new opportunities on how to perform known reactions, but the ILs can even be tailored to meet specific synthetic needs. One notable application of IL is the salt ability to act as solvent in many organic reactions is known to accelerate product formation or alter the selectivity of the reaction. For example, in the Diels-Alder reaction, where higher reaction rate and selectivity are obtained in polar solvents compared to non-polar solvents [17]. However, the vast applications of ILs are not without problems, one being that yields, purity and selectivity can vary according to the batch of ionic liquid used and the methods used to synthesis and purify the ILs. Therefore it is of great interest to study methods on how to minimize this problem.
The Objective of Research.
The objective of this research is to synthesize and characterize eight ionic liquids using 1-methylimidazole as the starting material by using the alkylation and metathesis synthesis methods. H1-NMR and Ion Chromatography (IC) analysis will be used to verify the characteristic and presence of impurities to determine the purity of
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