Synthesis of [70]azafulleroids: Investigations of azide addition to C-70

Treatment of C-70 with (2-methoxyethoxy)methyl azide gives rise to three out of a possible six triazoline isomers, showing chemoselectivity as well as regioselectivity: The major product arose from addition of azide to the double bond of C-70 possessing the greatest local curvature. Selective thermolysis of the least stable triazoline, the one resulting from addition to the least curved [6,6] double bond, allowed solution of the structure of the three isomers. Thermolysis of the triazoline isomers produced mixtures of C-70, azafulleroids, and fulleroaziridines.