Hexakis(dimethylamino)benzene is anodically oxidized to its chemically stable dication in an electrochemically slow two-electron process. This redox process was characterized by cyclic voltammetry, chronoamperometry, chronocoulometry, and bulk electrolysis with isolation of the bis(hexafluorophosphate) of the dication. The crystal structure of this dication salt shows considerable distortion, in accord with earlier results for the bis(triiodide). The sluggishness of the electron transfer is related to structural changes during oxidation: two noncoplanar polymethine systems coupled by two long C ± C single bonds form. The thermodynamics of the oxidation is characterized by inversion of potentials and disproportionation of a hypothetical radical cation. In contrast to earlier reports, no particular destabilization of the dication is assumed. Further oxidation of the dication proceeds via a tri-to a tetracation in two steps. The tri-and tetracations undergo chemical follow-up reactions.

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In contrast to earlier interpretations the two‐electron process yielding 12+ from the electron‐rich compound hexakis(dimethylamino)benzene 1 is characterized as being chemically reversible, but electrochemically quasireversible (right). Inversion of potentials and sluggishness of electron transfer are related to structural changes of the molecule during oxidation. Further electron transfers to tri‐ and tetracation oxidation stages are additionally observed.

The syntheses and the electrochemical behavior of the monomeric peralkylated hexaamino(1,3)metacyclophane 4, the dimeric dodecaamino(1,3)cyclophane 5a, and the dodecaamino(1,3,5)cyclophane 6 are described. Electrochemical measurements show that the hexaaminobenzene units in 4 and 5a undergo an unusually slow two-electron transfer attributed to the deformation of the rings into bis-cyanine cations when oxidized to the respective dication. Further oxidations to tri-, tetra-, and hexacationic units occur at more positive potentials. In the dimeric structures, no interaction between the rings can be seen in the (1,3)cyclophane, but strong interaction for the (1,3,5)cyclophane is observed.

Boron subhalide cluster dianions B6X 2- 6 (X = Cl, Br, I) are electrochemically oxidized in two steps. According to cyclic voltammograms, the first step is chemically reversible and yields the corresponding radical anions B6X .- 6. The electron transfer is nearly diffusion controlled. The second, slower electron-transfer step leads to a species which we assume to be the hitherto not yet described neutral compounds B6X 2- 6. The voltammograms indicate a coupled fast catalytic reaction, producing the radical anions in a reduction by an electrolyte component. Computer simulations of the cyclic voltammograms reveal mechanistic details of the redox reactions, as well as quantitative values for formal potentials, rate constants, and diffusion coefficients. The results are compared to other BnXn redox systems.