Anion Radical Formation from the Mixture of Polyamine Polymer and 7, 7, 8, 8-Tetracyanoquinodimethane

Abstract

It was found that triiodide ions (I3-) were prgduced from the mixture of polyamine polymer (1) and iodine molecule (12) via charge-transfer (CT) complex formation between them, Its velocity was extremely greater in(1)-I2 system than in its low molgcular weight model compounds-I2 systems. The causes of accelerating the reaction in polymeric systems have been clarified. They were the increments of local donor concentration and of local polarity around the active sites in the polymer chain because the donor nitrogen atoms are fixed on the main chain in contrast with those of the monomer analogues.
Then the reaction of (1) with 7, 7, 8, 8- tetracyanoquinodimethane (CQ), which is one of the rr-acceptorsof large size, was investigated. The rate of formation of CQ anion radicals in polymerie system (pseudo first order reaction) was almost the same as that in itsmodel compound systems. This might be explained by the steric hindrance-of the polymer chain because CQ molecule was too large to approach to the donor sites ofthe polymer chain as I2 in the (1)-I2 system. It was also suggested that this reaction proceeded through direct one electron transfer from donor to acceptor moieties and not through CT complex formation.