In a continuation of our efforts to understand the surface chemistry of all-carbon macromolecules, the reactivity of large fullerenes (C70 and greater) and carbon nanotubes were characterized. A systematic, time-dependent HPLC investigation of fullerenes (C60, C70, C78, C84) undergoing the Prato reaction was obtained. The substituted pyrrolidine functional group on a fullerene was added by refluxing ferrocenecarboxaldhyde, sarcosine and fullerene for 3 to 6 hours in toluene. Despite the multiple functional sites of these fullerenes, the stoichiometry of the reaction allowed for us to control the number of additions to the surface of the fullerenes. According to HPLC retention times, we observed three groupings of products for the reaction, which we hypothesize to be the mono-, di-, and tri-functionalized adducts. For all four of the fullerenes studied, the retention times of the tri-, di-, mono-, and unfunctionalized fullerenes increased respectively on the HPLC. We separated an isomeric mixture of two monofunctionalized C70 with a preparatory HPLC column. Each isomer retained its own unique composition, meaning that the two isomers did not exist in equilibrium. We used a similar technique to isolate the single monofunctionalized product of C60. IR spectroscopy, UV-Vis, and NMR helped characterize the functionalized products. Additionally, calculations of HOMO/LUMO energy levels were made using Jaguar. The same stoichiometric calculations were used to carry out the fictionalization of signal- and multi-walled carbon nanotubes. We used XRF to characterize the nanotubes by identifying iron's present in them.
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