Electrosynthesis and Characterization of 1,2-Dibenzyl C₆₀: A Revisit

A reinvestigation of the reaction between C602- and benzyl bromide in benzonitrile containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) has shown that there are more reaction products than previously reported. Use of a silica rather than a “Buckyclutcher I” column for HPLC purification led to isolation of two previously unattained products in the reaction mixture, one of which was identified as 1,2-(PhCH2)2C60 by UV−vis and NMR . The earlier incorrectly assigned 1,2-(PhCH2)2C60 was identified as the methanofullerene C61HPh by X-ray single-crystal diffraction. The electrochemistry of genuine 1,2-(PhCH2)2C60 shows that its first reduction potential in PhCN containing 0.1 M TBAP is cathodically shifted by 100 mV with respect to E1/2 for reduction of 1,4-(PhCH2)2C60, indicating that the addition pattern significantly affects the electrochemistry of derivatized C60. Visible and near-IR spectra of the monoanion and dianion of 1,2-(PhCH2)2C60 are also reported.