Potentiometric titration of phenols in nonaqueous solvents

Phenolic and carboxylic acids have been potentiometrically titrated in nonaquous solvents such as pydine, N,N-dimethylformamide(DMF) and ethylenediamine. Nonaqueous solutions of sodium methoxide is used as the titrant and a platinum and standard sleeve-type calomel electrode pair is used with a vibrating reed electrometer. Titration curves are obtained in Pydine which span a potential range two to three times as great as those obtained in DMF or Ethylenediamine. Many mixtures of protonic acids and phenols can be differentiated potentiometrically.