Invoking Pairwise Interactions in Water‐Promoted Diels–Alder Reactions by using Ionic Liquids as Cosolvents

Abstract

Rate constants and derived activation parameters of organic reactions in aqueous media, in particular Diels-Alder reactions, are sensitive to the presence of cosolvents in water. To enhance the solubility window of water, we introduced ionic liquids as cosolvents in the aqueous Diels-Alder reaction between anthracene-9-carbinol and N-ethylmaleimide. The reactive potentials of the organic compounds are parameterized by using semi-empirical quantum chemical methods. The principle of Savage-Wood additivity of group interactions is used to quantify the pairwise group interactions among chemically inert ionic liquids and organic reactants, both at initial and transition states of the reaction. The present approach shows promise, as the use of simple calculations from easily available kinetic data can help researchers to understand the versatility of green ionic-liquid alternatives to volatile organic solvents.

Thermal, electrical and structural studies on ionic liquid confined in ordered mesoporous MCM-41

“…41 Physicochemical properties of ionic liquids change in the presence of impurities like water, organic solvents and halide ions. [42][43][44] Therefore, prior to conning IL into the mesoporous MCM-41 support, IL as well as IL containing MCM-41 mesoporous materials were dried at 100 C under vacuum (10 À3 torr). Fig.…”

Experimental and theoretical studies on solvation in aqueous solutions of ionic liquids carrying different side chains: the n-butyl-group versus the methoxyethyl group

“…The effect of decreasing viscosity on reactivity was nicely demonstrated by the observed increase in the rates of Diels-Alder reactions as a result of decreasing the viscosity of the medium, both for pure ILs and their aqueous solutions. 23,24 The use of aqueous ILs for pulp fractionation, ber spinning, 25 and as additives for improving dying of natural and synthetic bers 26 are interesting examples of the potential applications of green chemistry to improve these important industrial processes.…”

Ionic liquids: “normal” solvents or nanostructured fluids?

“…In an effort to single out the effect of pairwise interactions between ILs and reactants on the rate of the process, 91 the same authors devised a model relating the ratios of reactivity measured in purely aqueous media and in dilute aqueous solutions of ILs, with the magnitude of these pairwise interactions. It is shown that in the presence of some ILs, reactivity is explained in terms of pairwise interactions, whereas others interact through bulk interactions.…”