When Functionalization Becomes Useful: Ionic Liquids with a “Sweet” Appended Moiety Demonstrate Drastically Reduced Toxicological Effects

Abstract

The growing number of applications of ionic liquids (ILs) in industry have brought attention to the green credentials of synthesis, as well as their cyto-and ecotoxicities both for their use and accidental leakage into the environment. With the above in mind, we designed a class of ILs with either cations bearing gluconamide motif and aliphatic side chains or the anion incorporating gluconic acid (derived from food waste) moiety. An ionic liquid with imidazolium cation with an appended gluconic amide (bearing 5 hydroxyl groups) moiety was also synthesised for a useful comparison. Different structural features were considered, placing emphasis on the nature and length of the alkyl chain and the nature of the anion. For comparison, two ILs with one hydroxyl group and another without any hydroxyl-groups were prepared.

Insights into the Properties and Potential Applications of Renewable Carbohydrate-Based Ionic Liquids: A Review

“…Billeci et al [ 11 , 17 ] pioneered a third approach to IL synthesis using glucono-δ-lactone ( Figure 3 ). A gluconamide derivative was formed through a reaction in methanol with either N , N -dimethylethylenediamine or N , N -dimethylpropylenediamine.…”

“…In addition to [Ch]ILs, carbohydrates have also gained attention as starting materials for synthesizing non-toxic and biocompatible ILs. Carbohydrate-derived ILs generally exhibit very low (eco)toxicity towards bacteria [ 37 ], fungi [ 37 ], human cancer cells [ 17 ], mouse cells [ 13 , 39 ], rat cells [ 54 ], and zebrafish eggs [ 17 ], indicating a promising biocompatible character.…”

“…Currently, broadened perspectives regarding potential IL applications span electrochemistry [ 10 ], energy storage [ 11 , 12 ], anti-bacterial systems [ 13 , 14 ], herbicides [ 15 ], and biomass conversion [ 16 ]. Carbohydrates have also recently been shown to reduce toxicity when incorporated into common imidazolium IL structures, thereby further enhancing their biocompatible character [ 17 ].…”

“…Although sugars are an economically favorable starting material, the process of manufacturing their ionic derivatives was originally complicated because of the required multiple-step synthetic method. Therefore, recent research efforts aimed at improving and simplifying the synthesis of carbohydrate-derived ILs have focused on implementing protocols to reduce the number of synthetic steps and/or integrate green chemistry approaches [ 11 , 17 , 18 ]. Such improvements have highlighted a more economically promising perspective regarding carbohydrate-based ILs and their applications.…”

WO3 and Ionic Liquids: A Synergic Pair for Pollutant Gas Sensing and Desulfurization

“…The tailoring property is very useful also in this context. Indeed, a suitable choice of substituents on the cation or anion structure allows the impact of these solvents to be significantly decreased, both on the environment and human health [102]. On this subject, aliphatic cations are generally preferred to aromatic ones, and among the anions, the ones deriving from amino acids, alkyl sulphates, halides and sugar-based anions are considered the most environmentally friendly [103].…”