SOLVENT NUCLEOPHILICITY - SCALE BASED ON TRIETHYLOXONIUM ION SOLVOLYSIS

First-order rate coefficients have been obtained for the solvolysis of triethyloxonium hexafluorophosphate in a variety of organic and aqueous-organic solvents. These have been used to set up a scale of solvent nucleophilicities based upon the four-parameter (two-term) Grunwald-Winstein equation. The required corrections for variation in solvent influence upon the leaving group were estimated from data available for tert-butyldimethylsulfonium ion solvolysis. A previously established scale, based upon methyl p-toluenesulfonate solvolysis, can be brought into good agreement with this scale if a revised value is used for methyl p-toluenesulfonate sensitivity to the electrophilic influence of the solvent. The scale is applied to previously studied solvolyses of alkyl p-toluenesulfonates and chlorides. © 1979, American Chemical Society. All rights reserved.