Ionic Liquids: Synthesis and Applications in Catalysis

Abstract

Ionic liquids have emerged as an environmentally friendly alternative to the volatile organic solvents. Being designer solvents, they can be modulated to suit the reaction conditions, therefore earning the name "task specific ionic liquids. " Though primarily used as solvents, they are now finding applications in various fields like catalysis, electrochemistry, spectroscopy, and material science to mention a few. The present review is aimed at exploring the applications of ionic liquids in catalysis as acid, base, and organocatalysts and as soluble supports for catalysts.

Ionic Liquids: An Emerging Tool for an Improved Organic Synthesis

“…In view of the acidic behavior of ionic liquids, the replacement of harmful acids by reusable ionic liquids is one of the great catalytic systems in organic synthesis. The ionic liquids possessing acidic behavior were exploited as catalysts for many organic transformations like Koch carbonization, Pechmann reaction, AzaMichael reaction, aldol condensation, esterification of alcohols, Beckmann rearrangement, oxidation reaction, Prins reaction and Mannich reactions to mention a few [5].…”

“…After that several classes of ionic liquids and their applications in the various areas have been reported. In 1999, the concept of designing ionic liquid to interact with a solute in a specific manner was demonstrated and introduced the term "task specific ionic liquid" [5].…”

Synthesis of Some Derivatives of 4-phenyl-1,3-dihydro-2H-imidazole-2-thion Using Ionic Liquid as Catalyst and Evaluation of Their Antimicrobial Activity

“…These salts are formed of organic cation and inorganic anions (Ratti, 2014). Ionic liquids have been applied widely as alternative solvents to support green chemistry considering particular physical and chemical properties (Selva, Perosa, Guidi, & Cattelan, 2016).…”

“…Besides this common usage, ILs appear to be applied as green catalysts for the replacement of conventional catalysts (Ratti, 2014;Olivier-Bourbigou, Magna, & Morvan, 2010;Zhao, Wu, Kou, & Min, 2002).…”

“…Due to the functional groups of the cation or anion in ILs, they can be considered as acidic, basic or organic catalysts (Ratti, 2014).…”