New mono- and polyazafulleroids C60(NR)n (n=1, 2, 4, 6) derived from a chiral azide containing N- and O-donor groups, and reactivity with [RhCl(CO)2]2

Reactions in a 1:1 molar ratio of the chiral azide (2S,4S)-4-azido-1-benzyloxycarbonyl-2-(tbutylaminocarbonyl)pyrrolidine (N3R, R=C17H23N2O3, 1) with C60 in ClPh, in the temperature range 100–132°C, lead to mixtures of mono- and polyazafulleroid species of general formula C60(NR)n (n=1, 2, 4), with a composition depending on the reaction conditions, and with a yield in the most substituted polyazafulleroids that increases with the concentration of reactants. However the reaction in a 1:6 molar ratio (fullerene–azide 1) leads only to hexaazafulleroids C60(NR)6. All mono- and polyazafulleroids C60(NR)n react with [Rh(CO)2Cl]2 to give complexes of composition C60(NR)n[Rh(CO)2Cl]n, which could be used as catalysts in asymmetric hydrogenation of prochiral olefins.