Charge-transfer interaction of iodine with some polyamidoamines

The interaction of iodine as a σ-acceptor with two derivatives of polyamidoamine dendrimers (donor), 1,8-naphthalimide polyamidoamine (PAM1) and 4-piperidino-1,8-naphthalimide polyamidoamine (PAM2) have been investigated spectrophotometrically at room temperature in chloroform. The results indicate the formation of two CT-complexes [(PAM1)I] +I 3 − and [(PAM2) 2I] +I 3 − with molar ratios of 1:2 and 1:1, respectively. The formation of these two complexes are in good agreement with their elemental analysis, infrared measurements and photometric titration plots based on the characteristic absorption bands of I 3 − ion around 280 and 360 nm. Moreover the formation of triiodide ion, I 3 −, in both of the two complexes was supported by measuring their spectra in the far-infrared region. Three characteristic bands are observed at 125, 110 and 75 cm −1 due to ν as(I–I), ν s(I–I) and δ(I 3 −), respectively, with C 2v symmetry.