ON THE DETERMINATION OF REDOX POTENTIALS OF HIGHLY REACTIVE AROMATIC MONOCATIONS AND MULTICATIONS

Thermodynamic redox potentials of reactive mono-and multiple charged cations of aromatic systems can be accurately determined by cyclic voltammetry by using solvents such as SO2 or CH2C12, a sophisticated sample preparation technique, low temperatures, and an appropriate time scale in the experiment. These conditions allow inter alia the measurement, for the first time, of the redox potentials (vs Ag/AgCl) of the reversible mono-, dication (tri-or tetracation) formation of naphthalene (1.67 V), fluoranthene (1.46 V), triphenylene ([di] 2.49 V),α,α-binaphthyl ([mono] 1.58 V, [di] 1.86 V), benzo[c]benzo-[3,4]cinnolino[1,2-a] cinnoline ([tri] 2.75 V), hexamethoxytriphenylene ([tetra] 2.27 V), 5,5'-dimethyl-2,2'-bithienyl ([mono] 1.08 V, [di] 1.68 V), and 3,3'-dimethoxy-2,2'-bithienyl (0.79 V). © 1990, American Chemical Society. All rights reserved.