Facile Access to Azafullerenyl Cation C_(59)N~+ and Specific Interaction with Entrapped Molecules

摘要

The facile preparation of azafullerenyl cation C_(59)N~(+) has been achieved by the assistance of trifluoromethanesulfonic acid. The thus formed C_(59)N~(+) was quite stable in solution over 1 month and can be used as an intermediate for the electrophilic reaction. Applying this method to endohedral azafullerenes, corresponding cations (H_(2)@C_(59)N~(+) and H_(2)O@C_(59)N~(+)) were prepared and the dynamic behavior of entrapped molecules was studied on the basis of ~(1)H NMR relaxation time measurements. The results indicated that there is strong intramolecular C_(59)N~(+)···O~(δ−)H_(2) interaction in H_(2)O@C_(59)N~(+), which stands in contrast to isoelectronic H_(2)O@C_(60) with no electrostatic interaction. We also demonstrated that the magnetic shielding environment inside the C_(59)N~(+) cage closely resembles that for isoelectronic C_(60).