1,4-Di-tert-butyl-2,5-dimethoxybenzene (A) reversibly forms a radical-cation (B) at E1/2a = 1.15 V (Pt, vs. Ag+ AgCl (sat.) KCl, 18-degrees-C) in dry and in aqueous acetonitrile. B is stable in many solvents, is unreactive towards nucleophiles but reacts readily with radicals. This special activity pattern appears to be characteristic of electron rich radical-cations and is utilized to investigate the linkage of catalysed electro-oxidation of water to organic electrooxidations. When electrolysis of A is conducted in presence of both water and either RuCl3 . 3H2O or Ru(acac) it reacts to yield 2,5-di-tert-butyl-1,4-benzoquinone (D), with practically 100% selectivity. RuCl3 . 3H2O and Ru(acac)3 are catalysts for the electrooxidation of water and the role of electrogenerated radicals in the process is indicated, in support of previous work. RuCl3 . 3H2O also catalyzes the homogeneous oxidation of A to D by H2O2 in a semblance to the Fenton reaction.