Margarita Altable

Mass Spectrometry Studies of the Retro-Cycloaddition Reaction of Pyrrolidino and 2-Pyrazolinofullerene Derivatives Under Negative ESI Conditions

Substituted pyrrolidino- and 3-alkyl-2-pyrazolinofullerenes ionize under ESI and MALDI mass spectrometry conditions and negative mode of detection undergoing mass spectral fragmentations, which can be easily correlated with the reported results for the thermal and electrochemical retro-cycloaddition reactions of these compounds. 2-Pyrazolinofullerenes lead directly to a [60]fullerene product ion formed through a retro-cycloaddition process regardless of the substituents attached at the carbon and nitrogen atoms of the heterocyclic ring. These results are different from whose reported for the thermal and electrochemical processes. In contrast, pyrrolidinofullerenes undergo different fragmentative reactions depending upon the substituents (hydrogen, alkyl, or acyl) attached at the nitrogen atom of the heterocyclic ring leading eventually to the pristine C60 in the last step of the fragmentation pathway.

Highly efficient Pauson?Khand reaction with C60: regioselective synthesis of unprecedented cis-1 biscycloadductsElectronic supplementary information (ESI) available: experimental section. See http://www.rsc.org/suppdata/cc/b4/b402616k/

Fullerenes undergo regioselectively and highly efficiently the intramolecular Pauson–Khand reaction to afford a new type of unprecedented structure with three fused pentagonal rings on the same fullerene six-membered ring.