Synthesis of polyamines with pendant cyanoimidazole units and their electrochemical properties

Abstract

The 2-(1-methyl-4,5-dicyanoimidazolyl) group was attached to poly(diallylamine) and polyethylenimine, affording polymers containing an electron-withdrawing pendant group. The key to their preparation is high reactivity of 1-methyl-2-fluoro-4,5-dicyanoimidazole (1) toward nucleophilic aromatic substitution (NAS) reactions with aliphatic amines. Cyclic voltammograms of these polymers show reduction waves at −2.6 to −2.7 V vs. Ag/Ag + but no reoxidation waves, unlike those of monomeric and oligomeric model compounds, which are quasi-reversible. The cyclic voltammetry studies of oligomeric model compounds with different alkyl spacers show that the degree of quasi-reversibility decreases as dicyanoimidazoles are crowded together in a molecule, suggesting that a certain degree of chemical reaction occurs between reduced dicyanoimidazole groups. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2619–2629, 1998