Chemical Reactions of Cationic Metallofullerenes: An Alternative Route for Exohedral Functionalization. Issue 8 (24th January 2020)

• Record Type: Journal Article
• Authors: Hu, Yajing; Solé‐Daura, Albert; Yao, Yang‐Rong; Liu, Xuechen; Liu, Sijie; Yu, Ao; Peng, Ping; Poblet, Josep M.; Rodríguez‐Fortea, Antonio; Echegoyen, Luis; Li, Fang‐Fang
• Is Part Of: Chemistry. Volume 26:Issue 8(2020)
• Page Start: 1748
• Page End: 1753
• Publication Date: 2020-01-24
• Subjects: [5, 6]-open Bingel adduct -- carbanions -- carbocations -- fullerenes -- single electron transfer; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201904854
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: The chemistry of cationic forms of clusterfullerenes remain less explored than that of the corresponding neutral or anionic species. In the present work, M3 N@ Ih ‐C80 (M=Sc or Lu) cations were generated by both electrochemical and chemical oxidation methods. The as‐obtained cations successfully underwent the typical Bingel–Hirsch reaction that fails with neutral Sc3 N@ Ih ‐C80 . Two isomeric Sc3 N@ Ih ‐C80 cation derivatives, [5, 6]‐open and [6, 6]‐open adducts, were synthesized, and the former has never been prepared by means of a Bingel–Hirsch reaction with neutral clusterfullerenes. In the case of the Lu3 N@ Ih ‐C80 cation, however, only a [6, 6]‐open adduct was obtained. Density functional theory (DFT) calculations indicated that the oxidized M3 N@ Ih ‐C80 was much more reactive than the neutral compound upon addition of the diethyl bromomalonate anion. The Bingel–Hirsch reaction of M3 N@ Ih ‐C80 cations occurred by means of an unusual outer‐sphere single‐electron transfer (SET) process from the diethyl bromomalonate anion to the stable intermediate [M3 N@C80 (C2 H5 COO)2 CBr] . . Remarkably, the diethyl bromomalonate anion was found to act as both a nucleophile and an electron donor. Abstract : The chemistry of cationic forms of clusterfullerenes is explored in terms of formation, reactivity and regioselectivity. M3 N@ Ih ‐C80 (M=Sc or Lu) cations were generated by both electrochemical and chemical oxidation. The as‐obtained cations successfully undergo the typical Bingel–Hirsch reaction that fails with neutral Sc3 N@ Ih ‐C80 . The reaction of the cations occurs by means of an unusual outer‐sphere single‐electron transfer process.