Deep eutectic solvent as an operative media on structure‐reactivity relationships

Abstract

Deep eutectic solvents seem to be environmentally friendly solvents, particularly because they are prepared easily and have very low‐vapor pressures under ambient conditions. They are suitable candidates as green solvents for reaction media with special properties. To present this behavior, substitution reactions of some para‐ and meta‐substituted anilines with 1‐fluoro‐2,4‐dinitrobenzene have been spectrophotometrically investigated in varying mole fractions of ethaline as a deep eutectic solvent in dimethyl sulfoxide (DMSO). The measured rate coefficients of the reaction demonstrated a noticeable variation with the increasing mole fraction of ethaline in ethaline‐DMSO mixtures. The linear free energy relationship (LFER) of second‐order rate coefficients based on Hammett's substituent constants demonstrates a reasonably linear straight line with a negative slope in different mole fractions of ethaline‐DMSO mixtures. Another LFER investigation based on the polarity parameters of the media showed a good agreement with hydrogen bond donor and acceptor abilities of the solvent. Non‐LFER assay according to the preferential solvation model confirmed differences between the microsphere solvation of the solute molecules and the bulk composition of the solvents.

A Comprehensive Study of Density, Viscosity, and Electrical Conductivity of (Choline Chloride + Glycerol) Deep Eutectic Solvent and Its Mixtures with Dimethyl Sulfoxide

“…These {glyceline+DMSO} mixtures, which are stable over the entire composition range for temperatures T ≥ 293.15 K, are of practical interest due to their significantly lower viscosity compared to neat glyceline. Recently, DESs mixed with DMSO have been considered as operative media for substitution reactions of para- and meta-substituted anilines with 1-fluoro-2,4-dinitrobenzene. , The employed DESs were 1:2 ChCl/ethylene glycol, usually called ethaline, , and glyceline . The analysis of the solvent effect on the reaction kinetics showed that the reactants and intermediate products are preferentially solvated by DES components and DMSO, respectively, which can be used as a factor of controlling the reaction rate.…”

Expected and unexpected products from reacting Sanger’s reagent with p-phenylenediamine

“…2 (d, F-C-C 2,4-Dinitrofluorobenzene 1 (200 mg, 1.1 mmol) in EtOH (15 mL) was mixed with aniline (200 mg, 2.2 mmol) for 3 h at room temperature. 25 The precipitate was filtered and air dried to give the title compound (130 mg, 46 %) as orange/ red crystals, m.p. 158-159 °C (from dichloromethane:light petroleum ether).…”

Interdependence of the Hammett and isokinetic relationships: a numerical simulation approach

“…Let us start by considering a homologous reaction series that follows either the Hammett or the Taft equation irrespectively of temperature (within a certain range). In the hypothetical case chosen as an example, the reaction constant (slope of the LFER-type plot) is negative (  or *  < 0), corresponding to a favorable effect of the electron-donating substituents [55,56], whereas a positive value (  or *  > 0) would correspond to a favorable effect of the electron-withdrawing substituents [57,58].…”