Isolation and characterisation of two oxahomofullerene derivatives of C60F18

From the products of the reaction of [60]fullerene with K2PtF6 under vacuum at 465 degreesC we have isolated two minor isomers of C60F18O, and charact erised them by EI mass spectrometry, IR and F-19 NMR spectroscopy. Calculat ions, the NMR spectra, thermal degradation, and the lack of evidence for th e existence of precursors for the formation of epoxides indicate that, like the major isomer recently fully characterised, both are ethers. The result s emphasise that oxides of fullerene derivatives may be either epoxides or ethers. Calculations show a correlation between length of the FC-CF bonds a nd heat of formation of the ethers, reinforcing our previous conclusion tha t the bond length is a driving force for ether formation. Given this, one c an anticipate ether formation in other derivatised fullerenes which possess a long alpha,beta -bond.