KINETICS AND SELECTIVITIES FOR THE SOLVOLYSIS OF N,N-DIPHENYLCARBAMOYL CHLORIDE

Values for the specific rates of solvolysis of N,N-diphenylcarbamoyl chloride have been analyzed using the two-term Grunwald-Winstein equation, incorporating the N-T solvent nucleophilicity scale and the Y-Cl solvent ionizing power scale. The sensitivities of 0.23 +/- 0.04 to changes in N-T and of 0.58 +/- 0.03 to changes in Y-Cl are consistent with an S(N)1 pathway with extensive internal nucleophilic assistance and a weak nucleophilic solvation of the developing carbocation. Product studies have been performed in mixtures of water with methanol, ethanol, and 2,2,2-trifluorethanol (TFE) and in TFE-ethanol mixtures. Giving further support to the proposed S(N)1 mechanism, both the sensitivity to changes in solvent nucleophilicity and the product selectivities in aqueous ethanol and methanol parallel closely those previously determined for solvolyses of p-methoxybenzoyl chloride.