Cation radical salts of arenes have been the subject of much recent attention since the discovery of their very narrow ESR line (10–20 mG). The 2:1 fluornthenium salt, for example, exhibits 1-D stacks with a characteristic mode of overlap. In order to modify the electronic properties of the fluoranthene molecule, without disturbing its geometry and hence the possibility of a well defined stacking, we prepared an aromatic, closed-shell cation, “aza” analog of the fluoranthene. The efficient three-steps synthesis of isoindolo[1,2,3-de]quinolizinium bromide and its X-ray molecular structure are described. A TCNQ salt prepared by electrocrystallisation presents an activated conductivity ( σ RT = 5 ω −1cm −1), a single narrow ESR line ( ΔH RT = 310 mG) and a Pauli-like susceptibility down to 70 K.