Electrochemical studies of amines were performed by numerous workers at various conditions such as aqueous and non-aqueous solvent or at various pHs [1]. It was reported that electrochemical oxidation of aromatic amines is quite complex, and leads to a variety of products depending on their structure and electrolysis conditions [2]. The reported results indicated that hydrolization can occur in electrochemical oxidation of some amines, and rate of the hydrolysis is dependent to pH and the structure of molecule [3]. It was reported that amines with more positive oxidation potential (EpA1) have larger ΔGtot values and there is a linear relation between these parameters [4]. In this work firstly using the oxidation potential of 4-aminodiphenylamine (1) in pH=7 and calculated ΔGtot of it, and calculated ΔGtot studied diamine derivatives (2-9), oxidation potentials of the species (2-9) were estimated. The electrochemical oxidation of para diamine species indicates that these species convert to their p-quinone dimines via two electron process. Reported results show that electrogenerated p-quinone dimines participate in the hydrolysis reaction and are converted to their p-benzoquinones and rate of hydrolysis dependence to N=C bond orders. Secondly using structure of 4-aminodiphenylamine (1) in pH=1 and its NBO analysis rate of hydrolysis reaction for all studied species (1-9) were compared with each other. All calculations were performed using Density Functional Theory (DFT) B3LYP level of theory and 6-311G (p,d) basis set.
