An electrochemical, spectroscopic, and theoretical study of poly(2,3-diaminophenazine)

The electrochemical polymerization of 2,3-diaminophenazine is affected by the presence of light and oxygen, causing a significant increase in the rate of polymerization. The electrochemical properties of poly(2,3-diaminophenazine) films prepared under different conditions vary slightly and are different from the properties of the related poly(o-phenylenediamine). Isolation of the initial photoproduct shows that this compound is a 1,2-coupled dimer of 2,3-diaminophenazine, suggesting that the structural differences between poly(2,3-diaminophenazine) and poly(o-phenylenediamine) arise from different coupling positions between monomer units during polymerization. Visible reflectance spectra measured for the two polymers also indicate that poly(o-phenylenediamine) contains quinonediimine linkages not found in poly(2,3-diaminophenazine). Density Functional Theory calculations support this assignment.