Bis-functionalisation of C 60 via thermal rearrangement of an isolable fulleroaziridine bearing a ‘solubilising’ supermesityl ester moiety

Heating of C60 with the novel azidoformate 3 bearing a highly solubilising supermesityl group affords the first example of a nitrogen-bridged fullerene 4, with a σ-homoaromatic closed 6,6-aziridine structure, which by further heating can be induced to undergo rearrangement on the fullerene surface to form as the sole product, the closed isomeric oxazole derivative 5 with O and N vicinally bound to the fullerene framework at a 6,6-ring juncture