Hexaaminobenzene derivatives: Synthesis and unusual oxidation behavior

The syntheses and the electrochemical behavior of the monomeric peralkylate d hexaamino(1,3)metacyclophane 4, the dimeric dodecaamino(1,3)cyclophane 5a , and the dodecaamino(1,3,5)cyclophane 6 are described. Electrochemical mea surements show that the hexaaminobenzene units in 4 and 5a undergo an unusu ally 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 p otentials. 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)cyclo phane is observed.