TSILs in Acid- and Base-catalyzed Reactions

Imidazolium-based ionic liquids are the most investigated and used ILs to date. Related to their solvent properties, they are characterized by n values similar to water, by moderate tx values, which depend primarily on the cation, and by moderate values determined mainly by the anion. In particular, imidazolium ILs bearing a CH group between nitrogen atoms have larger tx values than those in which a methyl group is present on the connecting carbon atom. 

Nevertheless, in the category of acidic ILs can be also included ILs based on protic ammonium, pyrrolidinium, pyridinium and imidazolium cations. These salts are formed through the transfer of a proton from a Bronsted acid to a Bronsted base  

Related to their application in synthesis, protic ILs have been used in C-C bond-forming reactions (Knoevenagel condensations, Diels Alder reactions, alkylation and Henry reactions, aldol condensations and Mannich reactions) 

Ionic liquids with tertiary amines on the side chain are effective solvents for these reactions furthermore, tertiary aliphatic amines may act as a reducing 

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