Fullerene-Cation-Mediated Noble-Metal-Free Direct Introduction of Functionalized Aryl Groups onto [60]Fullerene.

Aryl[60]fullerenyl cations (ArC60+), which were generated by heating aryl[60]fullerenyl dimers (ArC60-C60Ar) to generate aryl[60]fullerenyl radicals (ArC60•) followed by oxidation using Cu(II) salts (Cu(BF4)2(aq)), were reacted with various functionalized aryl boronic acids to produce functionalized 1,4-diaryl[60]fullerenes. This protocol tolerated various functional groups, such as OH, NH2, COCH3, and Cl substituents, with yields reaching 93%. C60Ar1Ar2 (Ar2 = p-NH2C6H4) was used as a dopant in a photoactive CH3NH3PbI3 layer of a perovskite solar cell.