| Summary: | 碩士 === 國立暨南國際大學 === 應用化學系 === 91 === The oxidation potentials of triphenylamines containing nitro- group at the 2- and 4- positions of a phenyl group, cyano- or carboxylic acid group at the 3- and 4- positions are oxidized with peak potential at ＋1.48, ＋1.43 and ＋1.36 V, respectively. The CV exhibits irreversible oxidative waves, probably due to dimerization upon amine oxidation. When a phenyl group is substituted with amino- group at the 2- and 4- positions, the CV exhibits three irreversible oxidation waves at ＋0.63, ＋1.12 and ＋1.50 V.
A series of p-phenylenediamine derivatives have different electrochemical results for various substituted groups. For nitro- and cyano- substituted compounds, the CV and spectroelectrochemistry exhibit the same patterns. Compound NPD has two reversible redox couples in the oxidative scan at E1/2 = ＋1.00 and ＋1.28 V and compound CPD at E1/2 = ＋0.90 and ＋1.23 V. NPD and CPD exhibit absorption peaks at 416 and 340 nm, respectively. After one-electron oxidation, the absorption peaks at 862 and 875 nm, respectively, are generated. But after second-electron oxidation, the absorption peaks decrease. CV of compound APD shows two reversible redox couples at E1/2 = ＋0.40 and ＋0.70 V and two irreversible oxidative wave at Epa = ＋1.24 and ＋1.40 V. The spectral change for compound APD is different from those of NPD or CPD. No redox couples are obtained in oxidative scan by CV for CAPD. There is one reversible redox couples at E1/2 = －1.47 V in reductive scan and one irreversible reductive wave at Epc = －1.90 V.
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