Isolation and spectroscopic characterisation of C60F17CF2CF3 and isomers of C60F17CF3;: insertion of :CF2 into fluorofullerene C-F bonds

The perfluoroalkylfluoro[60]fullerenes C60F17CF2CF3 (C-s) and three isomers of C60F17CF3 [C-s (major, 65%), enantiomeric C-1 pair (minor, 35%)] have been separated by HPLC from the many products obtained by fluorination of [60]fullerene by K2PtF6 at ca. 465 epsilon degreesC. They have been characterised by F-19 NMR spectroscopy, and for the trifluoromethyl compound, by single crystal X-ray structure determination. The trifluoromethyl compound shows either extremely weak or no resonances for the CF3 group in the F-19 NMR spectrum, which led to an earlier misidentification of the major isomer in this compound as a CF2 derivative. Isolation of these compounds indicates that trifluoromethyl compounds are formed under these conditions by insertion of :CF2 groups (from fragmentation of other fluorinated fullerene cages) into C-F bonds.