Effect of Substitution on the Electrochemical and Xerographic Properties of Triarylamines: Correlation to the Hammett Parameter of the Substituent and Calculated HOMO Energy Level

It has been found that both the electrochemical and xerographic properties of a series of triarylamines vary with the nature (quantified by its Hammett parameter, σ) and the frequency of substituents that make up a triarylamine. Three series of triarylamines, encompassing a total of 35 compounds, have been synthesized by Ullman condensation of an appropriately substituted aniline with an excess of an appropriately substituted iodophenylene by a published procedure [Goodbrand, H. B.; Hu, N. X. J. Org. Chem. 1999, 64 (2), 670−674]. The xerographic properties, including transport properties, of a select number of compounds have been measured as solid-state solutions in polycarbonate-Z. The recorded xerographic properties varied with the measured oxidation potential ( E 1/2 ) of the molecule, which in turn correlates to both the Hammett parameter of the substituent and the calculated HOMO energy level of the triarylamine.