Nuclear magnetic resonance spectroscopy of diphenylallyl carbanions. Part I. The determination of equilibrium constants for ion pairing

Abstract

The results of a study of the ¹H n.m.r. spectra of the alkali-metal salts of 1,3-diphenylpropene in several different ethers provide further evidence for the existence of contact and solvent-separated ion pairs. The thermodynamic parameters ΔH° and ΔS° have been determined for the solvation process for the sodium salt in tetrahydrofuran and 2-methyltetrahydrofuran and for the potassium salt in tetrahydrofuran. The composition of ether complexes in C₆D₆ and the effect of methyl substitution in the 1-position have also been investigated.