Synthesis of 2-Aryl-5-alkyl-fulleropyrrolidines: Metal-Free-Mediated Reaction of [60]Fullerene with Aromatic Aldehydes and Inactive Primary Amines

The metal-free-mediated thermal reaction of [60]fullerene with aromatic aldehydes and inactive primary amines bearing electron-donating groups at the α-position afforded a series of 2-aryl-5-alkyl-fulleropyrrolidines, including the scarce 2-aryl-5-benzyl-fulleropyrrolidines as a mixture of cis and trans isomers. With rare exceptions, the mixture of cis and trans isomers could be easily isolated by column chromatography, with a preference of cis isomers as major products. A plausible mechanism for the formation of fulleropyrrolidines is also proposed.