Electrosynthesis of buckyballs with fused-ring systems from PCBM and its analogue
Weifeng Wang, Kaiqing Liu, Chuang Niu, Y. WANG, Yang‐Rong Yao, Zheng‐Chun Yin, Muqing Chen, Shi-Qi Ye, Shangfeng Yang, Guan‐Wu Wang
Abstract
Abstract [6,6]-Phenyl-C 61 -butyric acid methyl ester (PCBM), a star molecule in the fullerene field, has found wide applications in materials science. Herein, electrosynthesis of buckyballs with fused-ring systems has been achieved through radical α-C−H functionalization of the side-chain ester for both PCBM and its analogue, [6,6]-phenyl-C 61 -propionic acid methyl ester (PCPM), in the presence of a trace amount of oxygen. Two classes of buckyballs with fused bi- and tricyclic carbocycles have been electrochemically synthesized. Furthermore, an unknown type of a bisfulleroid with two tethered [6,6]-open orifices can also be efficiently generated from PCPM. All three types of products have been confirmed by single-crystal X-ray crystallography. A representative intramolecularly annulated isomer of PCBM has been applied as an additive to inverted planar perovskite solar cells and boosted a significant enhancement of power conversion efficiency from 15.83% to 17.67%.