Reaction of silver(I) and (II) fluorides with C60: thermodynamic control over fluorination level

Silver(I) fluoride is shown to be a weak fluorinating agent (FA) for C60 and gives mainly C60F18. Fluorination with silver(II) fluoride yields C60F44, a new compound, as the predominant product (>80% in the crude). Fluorination degree of fullerenes in reaction with binary metal fluorides is found to be mainly thermodynamically controlled. The correlation between the level of C60 fluorination and oxidising fluorinating strength of the metal fluorides used for fluorofullerene preparations is discussed, permitting development of a self-consistent quantitative scale for inorganic FAs.