Conducting discotic polyaromatic material with two unpaired electrons at oxidized state: Synthesis and properties.
CNRS - Université Denis Diderot, ITODYS (ITODYS), Place Jussieu, Paris F-75005, France
|Polyaromatic molecules having symmetry axis equal or larger than three, possess degenerate HOMO’s and LUMO’s. This opens the possibility to abtain radical anions or cations in a high spin state. Oragnic molecules having high spin state are attractive in the search of electrical conductivity, ferromagnetism and even superconductivity. Polyaromatic hydrocarbons are of interest as high spin-systems, because many of the monoradicals and diradicals are relatively stable systems. 
We report the electrohemical oxidation in acetonitrile of hexapyrrolyl benzene (HPyB) a polyaromatic heterocyclic compound. This oxidation leads to a discotic polyaromatic heterocyclic material (HPyB6a) and not to a linear polymer.  The electroactivity of this material shows two successive reversible redox waves corresponding to the transfer of two electrons and esr measurements at oxidized sate shows paramagnetic behaviour at room temperature.
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Presentation: Invited at E-MRS Fall Meeting 2007, Symposium D, by Mohamed Jouini
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-05-14 19:08 Revised: 2009-06-07 00:44