Synthesis, Characterization, and Unusual Behavior of a Perfluoroarylated Fullerene

Fullerenes and fullerene derivatives have attracted much attention due to their interesting optical and electronic properties. For example, further chemical elaborations of fullerenes possessing cyclo‐adducts (ie., phenyl‐C₆₁‐butyric acid methyl ester, PCBM,¹ and mono‐indene-C₆₀, ICMA²) have shown promising use in photovoltaic energy conversion. Mono‐hydrofullerenes, C₆₀RH, were shown as effective synthons for novel molecules³ with interesting physicochemical properties for various applications. The C‒H bond activation utilizing the acidic fullerenyl C₆₀‒H proton can be realized by the use of strong bases. For instance, the dimerization of two RC₆₀· radicals using NaOH in the presence of C₆₀RH was used to form RC₆₀‒C₆₀R.⁴

In this work, we use the labile hydrogen atom on C₆₀RH as a synthetic handle for further chemical elaborations, resulting in a novel perfluoroarylfullerene. One such product, a "fullerene-with-a-mohawk," was realized by the use of a base or by an one‐electron reductant. Products were characterized by ¹⁹F and ¹H NMR spectroscopy, mass spectrometry, cyclic voltammetry, X‐ray crystallography, and DFT calculations.

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