Correlation of the rates of solvolysis of the benzhydryldimethylsulfonium ion. Application of the aromatic ring parameter

Article abstract of DOI:10.1021/jo960909t

Values for the specific rates of solvolysis of the benzhydryldimethylsulfonium ion in 34 solvents have been analyzed using various forms of the extended Grunwald - Winstein equation. The specific rates are insensitive toward changes in solvent nucleophilicity (N_T) values, and they correlate best against a combination of Y⁺ values (based on the solvolyses of the 1-adamantyldimethylsulfonium ion) and aromatic ring parameter (I) values. Common-molecule return is observed, being especially powerful in solvents rich in fluoro alcohol; the logarithm of the associated mass law constant correlates inversely with the solvent NT values. The product selectivities in ethanol - water mixtures are also consistent with an S_N1 mechanism for the solvolyses.