Electropolymerized Films of Salen Complexes

Thin films of cr-bonded tetraazaannulenic complexes of cobalt were electrochemically synthesized. From a potential cycling applied to a platinum electrode in an electrolytic solution containing the monomer, the electrodeposition process occurred via a 6-6 polymerization of the monomers . Also, the electrochemical homopolymerization of M-78 (M = Ni, Cu) derivatives was thoroughly investigated , some of which were functionalized at the y-position . 

By the same manner, the electropolymerization of the copper complex of 80 (half-unit = 2,6-diacetylpyridine-mono(ethylene(liamine)) was performed, which led to an electroactive polymeric Him whose electrocatalytic properties towards biodegradable agrochemicals were evaluatedOne can cite the example of the electrooxidative polymerization of 81, a 3-[l-(2-amino-phenylimino)-ethyl]-6-methylpyran-2,4-dione Schiff base. The corresponding films are insoluble in most solvents, electroactive in water but electro-inactive in acetonitrile and they display electrocatalytic properties towards the oxidation of hydroquinone .  

ITO electrode (---). Potentials are referred to SCE. Reprinted from ref.[197]. Copyright 

Finally, innovative bimetallic complexes as dissymmetric ligands can easily be built, giving birth to an unprecedented class of metal Schiff base salen complexes that can be successfully electropolymerized concomitantly with an overoxidation process. The electrooxidation of 8-(3-acetylimino-6-methyl-2, 

4-dioxopyran)-1 -amino-naphthalene Schiff base in acidic aqueous solution yielded a polymer film on glassy carbon electrodes that showed a reversible well-defined redox system in aqueous acidic solution, as well as electrocatalytic activity towards oxidation of catechol andhydroquinone.  

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