Electron-Donating Ability of the Cyclopropyl Substituent in the Solvolyses of an α-CF3-Substituted Secondary-Alkyl Tosylate

Article abstract of DOI:10.1021/jo00019a037

The solvolysis rates of cyclopropyl(trifluoromethyl)carbinyl tosylate (1) have been determined in a series of aqueous alcohol, aqueous trifluoroethanol, and carboxylic acid solvents.Analysis of the rate data for percent internal-return isomerization and salt effects and correlation with Y_OTs values indicates that 1 underwent solvolysis by the k_Δ pathway.Comparison of the relative ability of cyclopropyl and phenyl groups to stabilize carbocation-like transition states in solvolysis reactions of the secondary systems RCH(Y)CH3 and RCH(Y)CF3 reveals that replacement of phenyl with cyclopropyl increases the rate in both systems by a factor of 10².