Valence tautomeric compounds involving nondixolene-type ligands are rare. The triple-helicate copper(II) complex [Cu-2(II)(L)(3)](ClO4)(4)center dot 3CH(3)CN (1) containing a redox-active N-heterocyclic ligand (L) has been prepared and displays VT equilibrium in solution, as established by electronic spectroscopy, electron paramagnetic resonance spectroscopy, and cyclic and differential pulse voltammetry carried out at variable temperatures. The process involves intramolecular transfer of an electron from one of the L ligands to a copper(II) center, leading to the oxidation of L to an L center dot+ radical with concomitant reduction of the Cu-II center to Cu-I, as shown by the equilibrium [(CuCuL center dot+L2)-Cu-II-L-I](4+) reversible arrow [(Cu2L3)-L-II](4+).