Further consideration of the correlation of the rates of solvolytic displacement of chloride ion from phosphorus (V)

Abstract

Specific rates of solvolysis of diphenyl (1) and bis(2,4-dichlorophenyl) (3) phosphorochloridate (chlorophosphate) have been determined by a conductivity technique. The available specific rates together with those determined earlier for bis(4-chlorophenyl) phosphorochloridate (2) have been analyzed in terms of the extended (two-term) Grunwald-Winstein equation. It is found that rather poor overall correlations found earlier for 1 and 2 and now for 3 are considerably improved when data points for 2,2,2-trifluoroethanol-ethanol and acetone-water mixtures are excluded. The large sensitivities toward changes in solvent nucleophilicity are consistent with a bimolecular process. The differences in nucleophilicity of an acetone-water mixture for attack at carbon or at phosphorus are discussed. Copyright (C) 2010 John Wiley & Sons, Ltd.