KOtBu-Promoted [3 + 2] Cycloaddition of Dimethyl Sulfoxide with Fullerenes

KOtBu-promoted [3 + 2] cycloaddition of dimethyl sulfoxide (DMSO) with fullerenes has been developed for facile and efficient one-pot synthesis of 1,2,3,4-cyclic sulfoxide-fused [60]/[70]fullerene dihydrides, which offers a versatile platform for the site-selective preparation of various fullerene multiadducts with a wide range of functional groups. The utility of these tetra-functionalized fullerenes is demonstrated by the successful application as electron-transport materials in perovskite solar cells.