Collect. Czech. Chem. Commun. 1987, 52, 830-837

Transfer of 1,1'-dialkyl-4,4'-bipyridinium dication (viologen) across the water-dichloroethane and water-nitrobenzene interfaces

Josef Hanzlík and Zdeněk Samec

The J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, 102 00 Prague 10-Hostivař


Transfer of viologen dications R2V2+ (R = methyl, ethyl, propyl, butyl, pentyl, heptyl or benzyl) across the water-1,2-dichloroethane and water-nitrobenzene interfaces has been studied by cyclic voltammetry. Effects of the changes in the viologen structure and in the composition of solutions of both phases on the voltammetric behaviour have been inspected. Ion association, in particular that occuring in the organic phase, has a considerable influence on the viologen dication transfer and plays the key role in the proposed charge transfer mechanism. From the conductivity measurements the association constants for viologen tetraphenylborates in nitrobenzene have been evaluated. From the voltammetric measurements the Gibbs energies of transfer of viologen dications across the water-nitrobenzene interface have been determined.