Dynamic NMR as a Nondestructive Method for the Determination of Rates of Dissociation. III. Ionic Dissociation of α-Chlorodibenzyl Sulfide

Rates of dissociation of α-chlorodibenzyl sulfide have been determined by dynamic NMR technique. Examination of the rates at various concentrations of chloroform-d solutions has confirmed that the rates are not dependent on concentration, thus establishing that the NMR measurement affords data of unimolecular dissociation. The salt effect seems to be very small since addition of tetraethylammonium bromide hardly affects the rates of dissociation. Rates of dissociation in o-dichlorobenzene are smaller than in chloroform-d. The main contribution to the decrease in rates is given by the increase in enthalpy of activation, indicating that the hydrogen-bonding ability of chloroform is favorable for ionic dissociation.