Regiochemistry of Azide Additions to [70]Fullerene

In this paper we report for the first time on the reaction of C₇₀ with alkyl azides and show that the 3+2]-cycloaddition occurs preferably at bond 7 followed by bond 5 to give two regioisomeric A/B-triazolines and one C/C-triazoline Thermal extrusion of N₂ from these triazolines leads to open 5,6]-bridged iminofullerenes as A/A- and B/C-isomers as well as to the ring closed 6,6]-bridged analogues as A/B- and C/C-isomers. These results are in line with the corresponding thermal reaction of C₇₀ with diazomethane.