Influence of the Methyl Group in the Electron Spin Distribution in N-Methyl Benzotriazole Anion Radicals

Benzotriazoles have many uses in pharmaceuticals and photovoltaics. N1-Benzotriazole derivatives can be used for antibacterial, antioxidant, and antifreezes among others, while the N2-Benzotriazole polymers easily accept electrons, allowing them to be used in organic photovoltaics. Although myriad chemical studies have been performed on these systems, it is interesting that studies involving their one electron reduction have largely been unexplored. We have performed alkali metal reductions on both of these molecular compounds in polar aprotic solvents to determine how the placement of the methyl group affects electron spin density within the triazole moiety. The anion radicals of both compounds were generated and detected using Electron Paramagnetic Resonance (EPR) spectroscopy. Our results reveal considerable differences in the distribution of electron spin within these two anion radicals