1H NMR spectroscopic studies of the conformational isomers of pyrrolidinofullerenes.
Mixed bis-adduct derivatives of C60 containing a pyrrolidine and a malonate methano group were synthesized. Three regioisomers, the e', the trans-2, and the trans-3, were isolated and characterized. In-depth NMR studies of these methano-pyrrolidinofullerenes showed that the nitrogen inversion on the pyrrolidine moiety is not a fast event in the 1H NMR time scale as previously regarded. Solvent effects, variable temperature experiments, and protonation of the pyrrolidine nitrogen are addressed.
Department of Chemistry, Clemson University, 219 Hunter Laboratories, Clemson, SC 29630-0973, USA.
Olena
O
Lukoyanova
Alex
A
Kitaygorodskiy
Claudia M
CM
Cardona
Luis
L
Echegoyen