The experimental HOMO and LUMO energies were estimated using cyclic and differential pulse voltammetry (CV and DPV) in DCM with 0.1 M tetra-n-butylammonium hexafluorophosphate as the supporting electrolyte (Figure ). The electrochemical data were referenced to Fc/Fc + and are reported relative to a saturated calomel electrode (SCE). Both compounds show two highly reversible reduction waves, typical behavior of the benzoquinone moiety. The first reduction potentials are -0.78, -0.79 and -0.76 V for MeTPA-BQ, tBuTPA-BQ and TPPA-BQ respectively.