(2-Hydroxyethyl)ammonium Lactates—Highly Biodegradable and Essentially Non-Toxic Ionic Liquids

Sanita Pavlovica, Andris Zicmanis, Elina Gzibovska, Maris Klavins, Peteris Mekss

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DOI: 10.4236/gsc.2011.13017                

Abstract

(2-Hydroxyethyl)ammonium lactates have been prepared by reactions of the corresponding (2-hydroxyethyl) amines with lactic acid and characterized by their 1H NMR, IR, and mass spectra. They have been quantita- tively analyzed by HPLC, and their water contents have been determined by the Karl-Fischer method. The title salts are low-melting solids or viscous liquids, and they belong to the class of polar, hydrophilic ionic liquids. The toxicity and chemical and biological degradation of the synthesized ionic liquids have been evaluated by methods described in European Standards. The measurements showed these ionic liquids to be highly biodegradable and only slightly toxic substances. Condensation reactions of benzaldehyde with ethyl cyanoacetate and with acetophenone have been performed in these materials as solvents. The possibility of simultaneously applying these ionic liquids as both solvents and catalysts for the mentioned reactions has been demonstrated, as well as repeated use of the same ionic liquid for a number of condensation reactions without any purification.

Keywords

Ionic Liquids, Biodegradation, Toxicity, Polarity, Condensation Reactions

Conflicts of Interest

The authors declare no conflicts of interest.

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