Preferential solvation in alkan-1-ol/alkylbenzoate binary mixtures by solvatochromic probes

The binary mixtures of methanol with (C(1)-C(4)) alkylbenzoates and of (C(1), C(3), C(5), C(7), C(9), C(11)) alkan-1-ols with methylbenzoate were used as solvents to look into the preferential solvation and intermolecular interactions of the solvatochromic indicators 2-nitroanisole, 4-nitroaniline, 4-nitrophenol, and Reichardt's dye by UV-vis measurements. The experimental data at 298.15 K have served to deduce the corresponding Reichardt and Kamlet-Taft parameters of the mixed solvents. The solvation effects exerted on the solvatochromic probes by the solvents used, either pure or binary mixed, were analyzed by means of the preferential solvation model. Likewise, the (1)H NMR, (13)C NMR, and IR spectroscopic parameters measured for the mixed solvents corroborate the structural effects. The sets of experimental data gathered shed abundant light on the underlying solute-solvent and solvent-solvent interactions. The alkanol/methylbenzoate mixtures display stronger solvation ability than the pure solvents.