title: Hiding and recovering electrons in a dimetallic endohedral fullerene: air-stable products from radical additions.
abstract: Fullerenyl radicals can be generated by addition of a free radical to a fullerene surface, by nucleophilic addition followed by one-electron oxidation, or by thermal dissociation of singly bonded fullerene dimers. However, fullerenyl radicals are usually very reactive and generally cannot be isolated. On the contrary, we have found that the reactions of the dimetallic endofullerenes, La2@Ih-C80 and La2@D5h-C80, with 3-chloro-5,6-diphenyltriazine resulted in mono-addition of the triazinyl radical to the fullerene cages to yield isolable fullerenyl radicals. The unusual stability of these fullerenyl radicals arises from the confinement of the unpaired electron to an internal, metal-metal bonding orbital. Accordingly, the fullerene cage protects the radical center from other reactive species. Furthermore, we demonstrate that the fullerenyl radical adduct of La2@Ih-C80 reacts with toluene to afford additional benzylation. Interestingly, the benzylated derivative is diamagnetic in solution, while it forms a paramagnetic dimer when crystallized.
authors.affiliation: Department of Chemistry, Tokyo Gakugei University , Tokyo 184-8501, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Yamada
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kurihara
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Suzuki
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Saito
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Slanina
authors.forename: Filip
authors.initials: F
authors.lastname: Uhlik
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Aizawa
authors.forename: Tatsuhisa
authors.initials: T
authors.lastname: Kato
authors.forename: Marilyn M
authors.initials: MM
authors.lastname: Olmstead
authors.forename: Alan L
authors.initials: AL
authors.lastname: Balch
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Maeda
authors.forename: Shigeru
authors.initials: S
authors.lastname: Nagase
authors.forename: Xing
authors.initials: X
authors.lastname: Lu
authors.forename: Takeshi
authors.initials: T
authors.lastname: Akasaka
mesh_terms: D000388:Air; D018360:Crystallography, X-Ray; D004583:Electrons; D005609:Free Radicals / Q000138:chemical synthesis / Q000737:chemistry; D037741:Fullerenes / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D005609:Free Radicals; D037741:Fullerenes; D028581:Lanthanoid Series Elements; D009942:Organometallic Compounds