Synthesis of an Azahomoazafullerene C₅₉N(NH)R and Gas‐Phase Formation of the Diazafullerene C₅₈N₂

Abstract

Open the cage if you dare: The azahomoazafullerene 1 was prepared from a tert‐butylperoxy‐substituted azafullerene derivative C59NBr(OOtBu)4. Singlet oxygen added to 1 to form an open‐cage azafullerene 2 with a ketoimide moiety on the rim of the orifice. The MALDI‐TOF mass spectrum of the product of the hydrolysis of 1 showed a clear signal for the diazafullerene C58N2 (see structure 3).

Punching a Carbon Atom of C60 into its Own Cavity to Form an Endohedral Complex CO@C59O6 under Mild Conditions

“…Fullerene-bound hydroxylamino group is prone to rearrangement as shown in our previous studies. [11,14,21] To expand the orifice we treated compound 4 with diacetoxyl iodobenzene (DIB). To our surprise, compound 5 with a CO molecule trapped in the cavity was isolated.…”

Dramatic Mechanistic Change in Acid‐Catalyzed Arylation of Azafulleroids Depending on their Ambident N/C Basicity: Formation of Cyclopentene Centered Pentakisadduct

“…In conclusion, we have found that the acid-catalyzed arylation of variously N-substituted [5,6] open azafulleroids much depended on the nature of the substituents R (= alkyl, benzyl, and phenyl group), because the initial protonation of the incorporated bridged enamine framework varies with the substituents. Alkylazafulleroid brought about the monoarylation via the [5,6] ring closure and the protonated aminobridge opening.…”

“…This reaction involves acid-induced C À N bond cleavage followed by the nucleophilic arylation and the closure of [5,6] open ring ( Table 1). The stronger protic acid CF 3 SO 3 H (TfOH) was practical for this arylation, similarly to the acidic arylation [a] Dr.…”

“…Alkylazafulleroid brought about the monoarylation via the [5,6] ring closure and the protonated aminobridge opening. However, benzylazafulleroid gave rise to tetrahydroisoquinolinofullerene via the preferential intramolecular cyclization.…”

“…

Abstract: Azafulleroid, amino-bridged [5,6]-open fullerene, has the ambident N/C basicity of the incorporated enamine moiety. Acid-catalyzed arylation of N-substituted azafulleroids proceeded via two types of initial N/C protonation to perform monoarylation or 1,4-bisarylation for the N-alkyl substituents and shuttlecock-type pentakisarylation for the N-phenyl substituent.

…”