Experimental determination of solubility of dihydropyridine derivatives in organic solvents at different temperatures: Interactions and thermodynamic parameters relating to the solvation process

A novel series of dihydropyridine derivatives were synthesized and characterization of all these synthesized compounds was done by IR, H-1 NMR,C-13 NMR and mass spectral data. For all these compounds, solubility was determined by gravimetric method in various polar and non-polar solvents such as methanol, ethanol, 1-propanol, 1-butanol, chloroform, ethyl acetate and 1,4-dioxane. It is found that solubility increases with temperature and is found to be greater in 1,4-dioxane for all the compounds. The modified Apelblat and Buchowski-Ksiazczak lambda h models were used to correlate the experimental solubility with temperature. Using Van't Hoff and Gibb's equations, some thermodynamic parameters such as Gibb's free energy, enthalpy and entropy of dissolution were also evaluated from solubility data. (C) 2016 Elsevier B.V. All rights reserved.