The facile preparation of azafullerenyl cation C59N+ has been achieved by the assistance of trifluoromethanesulfonic acid. The thus formed C59N+ 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@C59N+ and H2O@C59N+) were prepared and the dynamic behavior of entrapped molecules was studied on the basis of H-1 NMR relaxation time measurements. The results indicated that there is strong intramolecular C59N+center dot center dot center dot O delta-H2 interaction in H2O@C59N+, which stands in contrast to isoelectronic H2O@C-60 with no electrostatic interaction. We also demonstrated that the magnetic shielding environment inside the C59N+ cage closely resembles that for isoelectronic C-60.