ELECTROCHEMICAL REDUCTION OF SOME TRANSITION-METAL CRYPTATES - (222, M)2+ AND (221, M)2+

The electrochemical reduction of the solvated cations M2+ (M = Fe, Co, Ni) and of their cryptates (221, M)2+ and (222,M)2+ has been studied on a mercury electrode, in propylene carbonate, by normal and reverse pulse polarography, by cyclic voltammetry and by potentiostatic coulometry. The in situ complexation of the cations M2+ by the macrobicyclic ligands (221) and (222) has been observed. An unusual polarographic behaviour is observed with the cryptate (221, Ni)2+. © 1979 Elsevier Sequoia S.A.