Preferential solvation and association constants of 2-exo and 2-endo norbornyl chlorides in water–acetone mixtures

Abstract

Molecular dynamics simulations of 2-exo and 2-endo norbornyl chlorides are performed in water–acetone mixtures to investigate the role of preferential solvation on the dissociation process of norbornyl chlorides. Increase in the association constants between carbon (C2) and chloride (Cl) of norbornyl chlorides with an increase in mole fraction of acetone supports the experimental data for the corresponding decrease in the rates of solvolysis for both exo and endo norbornyl chlorides. When the mole fraction of water is increased in water–acetone mixtures, acetone molecules are replaced by water molecules around C2 as well as Cl of norbornyl chloride. Preferential solvation by water is analysed using running coordination numbers and excess coordination numbers around C2 and Cl.