Spectrophotometric and voltammetric study of the interaction between iodine and poly[bis(p-tolylamino)]phosphazene in methylene chloride

The reaction between iodine and polybis(p-tolylamino)]phosphazene (PTAP) in methylene chloride was investigated and attributed to a charge-transfer interaction between the imine donor sites of the polymer and the halogen molecules. The mechanism of this process seems to be similar to that already proposed for the charge transfer between p-toluidine and iodine. In particular, the formation of a polar “inner” complex is strongly favoured when a polar substance, such as tetrabutylammonium perchlorate (TBAP), is added to the polymer-iodine system. Even if experimental evidence was not obtained, iodination of the aromatic ring, following the “inner” complex formation, cannot be excluded.