Application of reaction field theory to the calculation of solvent effects on the Menschutkin reaction of tripropylamine with methyl iodide

Abstract

The reaction field theory previously applied to the calculation of solvent effects on ΔG^‡ values for the decomposition of t-butyl chloride has now been applied similarly to the Menschutkin reaction of tripropylamine with methyl iodide. Calculations have been carried out using a transition state model of µ= 7.60 D, corresponding to a charge separation of 0.396 units, and cover reaction in 68 aprotic solvents. There is good agreement (±0.2 kcal mol^–1) between calculated solvent effects and observed values of δΔG^‡ for 28 solvents, and it is suggested that in this set of solvents specific solvent effects are small or absent. The remaining 40 solvents, including aromatic solvents and polyhalogenated solvents, generally lead to δΔG^‡ values smaller than those calculated.