Kinetic studies of nucleophilic substitution reactions of para-substituted benzylchlorides with anilines were conducted in a range of MeOH-MeCN mixtures at $55.1^{circ}C$. Hammett ${ ho}_C$, ${ ho}_N$ values and Bronsted ${eta}$ values were determined, in other to examine the transition state variations caused by changes in nucleophiles, substituents and solvents properties (${pi}^{ast}$ and ${alpha}$). Applications of potential energy surface (PES) and quantum mechanical (QM) models of transitheion state characterization lead us to conclude that the reaction proceeds via the dissociative $S_N2$ mechanism.