Dimethyl sulfoxide/deep eutectic solvents mixtures as media in the reaction of 1‐fluoro‐2,4‐dinitrobenzene with piperidine: A solvent effect study

Abstract

Aromatic nucleophilic substitution reaction of 1‐fluoro‐2,4‐dinitrobenzene with piperidine was kinetically investigated in ethylene glycol‐choline chloride and glycerol‐choline chloride as 2 deep eutectic solvents (DESs) mixed with dimethyl sulfoxide, in whole mole fractions, at room temperature. The investigation of the reaction in different concentrations of the piperidine shows that the reaction follows the base‐catalyzed mechanism. The measured rate coefficients of the reaction demonstrated a sharp decreasing in all mixtures with the increasing mole fraction of DESs. Linear free energy relationship investigations confirm that hydrogen bond donor ability in addition to polarity‐polarizability of the media has a major effect on the reaction rate. The decrease in the rate coefficient is attributed to not only hydrogen‐bonding donor interactions of the media with piperidine as both reactant and catalyst but also the preferential solvation of reactants by DES compared with the intermediate of the reaction.

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.…”

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

“…FDNB is a good candidate for a nucleophilic aromatic substitution with the addition‐elimination mechanism. In continuing our recent study of solvent effects on organic reactions and similar studies, we were interested in studying effects of mixtures on DESs with molecular solvents. The reaction of FDNB with some substituted anilines was studied at 25°C in binary mixtures of ethaline and DMSO mixtures.…”

“…However, the solute-solvent interactions have been widely investigated by using the physical property Y as a solvatochromic parameter, 27,[31][32][33] the use of this model as a nonlinear relationship between activation free energy of chemical reactions and solvent composition (non-LFER) has demonstrated interesting results. 20,33,34 Equation 6 was applied for log k A , and the results are summarized in Table 4. Statistical parameters and good agreement shown in Figure 3 confirm the ability of Equation 6 in reproducing the reaction rate coefficients.…”

“…Many recent studies have focused on bulk physical properties, including phase diagrams information, viscosity, density, and electrical conductivity data, and the effect of molecular structure on the physical properties of DESs . A few academic reports can be found about the investigation of microscopic physical properties of DESs and the prediction of their influence on chemical reaction rates . Such studies provide deep insights into the necessary information to design new DESs with desirable properties.…”

“…19 A few academic reports can be found about the investigation of microscopic physical properties of DESs and the prediction of their influence on chemical reaction rates. 20 Such studies provide deep insights into the necessary information to design new DESs with desirable properties.…”