Electrochemical studies of sulfonates in non-aqueous solvents: Part I. Polarographic reductions of alkali metal ions with sulfonate supporting electrolyte in N,N-dimethylformamide and acetonitrile

The effect of the supporting electrolytes tetraethylammonium p-toluenesulfonate, methanesulfonate and trifluoromethanesulfonate on the polarographic reduction of alkali metal ions in N,N-dimethylformamide and acetonitrile has been investigated. In tetraethylammonium trifluoromethanesulfonate supporting electrolyte, the polarographic reductions of alkali metal ions are almost the same as those in perchlorate in both solvents. In tetraethylammonium p-toluenesulfonate and methanesulfonate, the half-wave potentials shift to more negative potentials, especially in acetonitrile. These shifts can be explained in terms of ion-pair formation between the alkali metal ion and the supporting electrolyte anion.