Infrared spectroscopic study of the interaction between 2,6-diarylphenols and alkyl cyanides

Abstract

The O–H stretching absorptions of 2,6-diarylphenols are composed of two symmetrical bands (intramolecular OH ⋯π and intermolecular OH ⋯ N interactions) in the presence of alkyl cyanides in carbon tetrachloride solution.

The equilibrium constants K for the competitive interactions were determined. The equilibrium study suggested that the K values depend on the dihedral angle between the phenol ring and the 2,6-aryl groups. Comparison of log K with ν₀(OH)(the frequency of the OH ⋯ N band at infinite dilution in CCl₄) revealed a linear relation. Furthermore it was found that the frequency shifts caused by the concentration of cyanide can be explained by the Kirkwood-Bauer-Magat relationship.