Facile access to 2,5-diaryl fulleropyrrolidines: magnesium perchlorate-mediated reaction of [60]fullerene with arylmethylamines and aryl aldehydes

Abstract

The facile one-step reaction of [60]fullerene with arylmethanamines and aryl aldehydes in the presence of magnesium perchlorate under air conditions generated a series of scarce 2,5-diaryl fulleropyrrolidines in good to excellent yields. Intriguingly, all the formed 2,5-diaryl fulleropyrrolidines were confirmed only as cis isomers and thus displayed high stereoselectivity. In addition, the type of aryl aldehyde was found to have a great correlation with the formation of different 2,5-diaryl fulleropyrrolidines. Aryl aldehydes without electron-withdrawing groups always afforded exclusively the desired 2,5-diaryl fulleropyrrolidines, while aryl aldehydes connecting electron-withdrawing groups unexpectedly produced symmetrical 2,5-diaryl fulleropyrrolidines besides the anticipated fulleropyrrolidines. A plausible formation mechanism for the 2,5-diaryl fulleropyrrolidines was proposed.