Influence du substituant tertiobutyl-4 sur les constantes d'acidité du cation cyclohexylammonium et de l'acide cyclohexane carboxylique dans les milieux mixtes eau–DMSO et méthanol–DMSO

Abstract

Acid dissociation constants for the compounds 1–6 in water–DMSO and methanol–DMSO of varying composition have been determined by a potentiometric method. In all solvents the equatorial group ionized more easily, by gain or loss of a proton, than the axial group, but in the more aqueous solvents the presence of a tert-butyl group across the cyclohexane ring inhibited this ionization slightly. An explanation based on displacement of solvent molecules from the outer solvation sphere is advanced.