A significant improvement in the selectivity of fullerene trifluoromethylation reactions was achieved. Reaction of trifluoroiodomethane with [60]fullerene at 460 degrees C and [70]fullerene at 470 degrees C in a flow reactor led to isolation of cold-zone-condensed mixtures of C-60(CF3)(n) and C-70(CF3)(n) compounds with narrow composition ranges: 6 <= n <= 12 for C-60(CF3)(n) and 8 <= n <= 14 for C-70(CF3)(n). The predominant products in the C-60 reaction, an estimated 40+ mol% of the cold-zone condensate, were three isomers of C-60(CF3)(10). Two of these were purified by two-stage HPLC to 80+% isomeric purity. The third isomer was purified by three-stage HPLC to 95% isomeric purity. Thirteen milligrams of this orange-brown compound was isolated (5% overall yield based on C-60), and its C-1-symmetric structure was determined to be 1,3,7,10,14,17,23,28,31,40-C-60(CF3)(10) by X-ray crystallography, The CF3 groups are either meta or para to one another on a p-m-p-p-p-m-p-m-p ribbon of edge-sharing C-6(CF3)(2) hexagons (each pair of adjacent hexagons shares a common CF3 group). The selectivity of the C-70 reaction was even higher. The predominant product was a single C-70(CF3)(10) isomer representing > 40 mol % of the cold-zone condensate. Single-stage HPLC led to the isolation of 12 mg of this brown compound in 95% isomeric purity (27% overall yield based on converted C-70). The new compounds were characterized by El or S8-MALDI mass spectrometry and 2D-COSY F-19 NMR spectroscopy. The NMR data demonstrate that through-space coupling via direct overlap of fluorine orbitals is the predominant contribution to J(FF) values in these and most other fullerene(CF3)(n) compounds.