Equilibrium acidities of HA2+ dications in dimethyl sulfoxide solution

A combination of the equilibrium acidities of weak acids with the oxidation potential of the acid and those of the corresponding A(super -) anions, A(super -) radicals, and HA(super +) radical cations enables the estimation of the acidities of HA(super 2+)-type dications. The instability of the radical cation prevents the measurements of the oxidation potential by cyclic voltammetry. The oxidation potentials of three acids are measured and examined.