Introduction.

In all chemical processes, a reaction medium or solvent is required, and such organic solvents are highly volatile so they are pollutants to the atmosphere, and new methods, processes and other solvents are required to minimize the contamination, and Ionic liquids are proving to be a great alternative to such problem.

Objective.

Synthesize imidazole based ionic liquids with both inorganic and organic anions and evaluate their potential application as catalysts in important reactions of organic synthesis, such as asymmetric synthesis, specifically in asymmetric aldol reaction.

Materials and Methods.

Methyl imidazole (99%), 1-bromobutane (97%), proline (98%), KOH (97%), Ethyl acetate, ethanol, reagent grade were supplied by Sigma Chemical Co. It was used the methyl imidazol for the synthesis of the ionic liquid butyl methyl imidazole bromide, [Bmim] [Br], and the other ionic liquids were obtained by metathesis reaction from such ionic liquid, to obtain the butyl methyl imidazole hydroxy [Bmim] [OH], and the butyl methyl imidazole prolinate, [Bmim] [Pro]. These ionic liquids were used as catalysts in the asymmetric aldol reaction.

Results.

A classical aldol reaction, p-nitrobenzaldehyde with cyclohexanone was performed to test the ionic liquids synthesized as catalysts, and when comparing the results obtained with conventional methods, advantages were observed, such as high yields and high selectivity in less time reaction.

Conclusions.

Under very mild reaction conditions, it was possible to reuse up to 6 times the ionic liquid as a reaction catalyst without losing the mentioned advantages, which makes it a sustainable system.

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