Unexpected formation of 1, 2- and 1, 4-bismethoxyl Sc3N@Ih-C80 derivatives via regioselective anion addition: an unambiguous structural identification and mechanism study. Issue 23 (13th May 2021)

• Record Type: Journal Article
• Authors: Hu, Yajing; Yao, Yang-Rong; Liu, Xuechen; Yu, Ao; Xie, Xiaoming; Abella, Laura; Rodríguez-Fortea, Antonio; Poblet, Josep M.; Akasaka, Takeshi; Peng, Ping; Zhang, Qianyan; Xie, Su-Yuan; Li, Fang-Fang; Lu, Xing
• Is Part Of: Chemical science. Volume 12:Issue 23(2021)
• Page Start: 8123
• Page End: 8130
• Publication Date: 2021-05-13
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d1sc01178b
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : An attempt to achieve heterocyclic cycloadducts of Sc3 N@ I h -C80 via reaction with Ph2 CO, PhCCPh or PhCN in the presence of tetrabutylammonium hydroxide (TBAOH) stored in CH3 OH led to the formation of the unexpected bismethoxyl adducts of Sc3 N@ I h -C80 (1 and 2 ). Abstract : An attempt to achieve heterocyclic cycloadducts of Sc3 N@ I h -C80 via reaction with Ph2 CO, PhCCPh or PhCN in the presence of tetrabutylammonium hydroxide (TBAOH) stored in CH3 OH led to the formation of the unexpected bismethoxyl adducts of Sc3 N@ I h -C80 (1 and 2 ). Further studies reveal that TBAOH in CH3 OH can boost the CH3 O − addition efficiently, regardless of the presence of other reagents. Single-crystal X-ray diffraction results firmly assign the molecular structures of 1 and 2 as respective 1, 4- and 1, 2-bismethoxyl adducts, and reveal unusual relationships between the internal Sc3 N cluster and the addition modes, in addition to the unusual packing mode in view of the orientation of the methoxyl groups. Electrochemical results demonstrate smaller electrochemical gaps for 1 and 2, relative to that of Sc3 N@ I h -C80, confirming their better electroactive properties. Finally, a plausible reaction mechanism involving anion addition and a radical reaction was proposed, presenting new insights into the highly selective reactions between the methoxyl anion and metallofullerenes. 1 and 2 represent the first examples of methoxyl derivatives of metallofullerenes. This work not only presents a novel and facile strategy for the controllable synthesis of alkoxylated metallofullerene derivatives, but also provides new non-cycloadducts for the potential applications of EMFs.