New electropolymerizable aromatic compounds (i.e. pyrrole, thiophene, aniline) bearing boronic acid and ester substituents have been synthesized and their electrochemical behavior has been investigated. Functionalized polythiophene and polypyrrole films could be anodically generated in acetonitrile, whereas the polyaniline derivative was electroformed in an acidic aqueous solution. The electrochemical responses of some of these materials were changed when fluoride ions were added to the electrolytic solutions. The strongest modifications, caused by binding of fluoride by the immobilized boron, were observed for the polypyrrole derivative in hydroorganic media.

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Primary alkyl iodides (RI) have been found to react with a cathodically charged glassy carbon surface at potentials more negative than -1.7 V vs Ag/AgCl. In aprotic solvents, this reaction results in grafting of the alkyl chains onto carbon. It is proposed that the process corresponds to the cathodic charge of graphitized and fullerenized zones present in carbon followed by a displacement reaction (analogous to a nucleophilic attack) toward alkyl iodides. This new mode of grafting is applied to the immobilization of ferrocene used as an electrochemical probe. The present work points out the reaction of ω-iodoalkylferrocenes and quantifies the level of grafting of alkyl chains via this promising method for modification of carbon surfaces. Coverage levels were found to be high, reaching the apparent surface concentrations of 8 × 10(-9) mol cm(-2). These large values are explained on the basis of swelling of the interface provoked by progressive charging of the carbon surface via insertion of tetraalkylammonium cations concomitantly with the substitution process. Alkylferrocene layers deposited onto carbon were found to be chemically and electrochemically stable.