Stergiou, A., Rio, J., Griwatz, J. H., Arcon, D., Wegner, H. A., Ewels, C. P. & Tagmatarchis, N. (2019) A Long-Lived Azafullerenyl Radical Stabilized by Supramolecular Shielding with a [10]Cycloparaphenylene. Angew. Chem.-Int. Edit.
Added by: Richard Baschera (2019-12-20 09:42:21) Last edited by: Richard Baschera (2019-12-20 09:48:47) |
Type de référence: Article DOI: 10.1002/anie.201909126 Numéro d'identification (ISBN etc.): 1433-7851 Clé BibTeX: Stergiou2019 Voir tous les détails bibliographiques |
Catégories: INTERNATIONAL, PMN Mots-clés: [10]cycloparaphenylene, azafullerenes, c59n, cycloparaphenylenes, dimer, energy-conversion, esr, host-guest complexes, long-lived radicals, nanoscale, photoinduced radical generation Créateurs: Arcon, Ewels, Griwatz, Rio, Stergiou, Tagmatarchis, Wegner Collection: Angew. Chem.-Int. Edit. |
Consultations : 1/580
Indice de consultation : 7% Indice de popularité : 1.75% |
Résumé |
A major handicap towards the exploitation of radicals is their inherent instability. In the paramagnetic azafullerenyl radical C59N., the unpaired electron is strongly localized next to the nitrogen atom, which induces dimerization to diamagnetic bis(azafullerene), (C59N)(2). Conventional stabilization by introducing steric hindrance around the radical is inapplicable here because of the concave fullerene geometry. Instead, we developed an innovative radical shielding approach based on supramolecular complexation, exploiting the protection offered by a [10]cycloparaphenylene ([10]CPP) nanobelt encircling the C59N. radical. Photoinduced radical generation is increased by a factor of 300. The EPR signal showing characteristic N-14 hyperfine splitting of C59N.subset of [10]CPP was traced even after several weeks, which corresponds to a lifetime increase of {>}10(8). The proposed approach can be generalized by tuning the diameter of the employed nanobelts, opening new avenues for the design and exploitation of radical fullerenes.
|