Synthesis of 1,4-diaryl[60]fullerenes by bis-hydroarylation of C60 and their use in solution-processable, thin-film organic photovoltaic cells

An AlCl3-mediated Friedel–Crafts reaction of arenes with C60 affords two-fold hydroarylated compounds, C60Ar2H2, which upon deprotonation with tBuOK and oxidation with CuBr·SMe2 yield 1,4-diaryl[60]fullerenes, C60Ar2 (Ar = Ph, 4-Me-C6H4, 3,4-Me2-C6H3, and 4-Ph-C6H4) in good yield. A solution-processed, thin-film organic photovoltaic device using C60(4-PhC6H4)2 as electron acceptor material showed a 2.3% power conversion efficiency.