Crystallographic Evidence for Direct Metal–Metal Bonding in a Stable Open‐Shell La2@Ih‐C80 Derivative. (25th February 2016)

• Record Type: Journal Article
• Authors: Bao, Lipiao; Chen, Muqing; Pan, Changwang; Yamaguchi, Takahisa; Kato, Tatsuhisa; Olmstead, Marilyn M.; Balch, Alan L.; Akasaka, Takeshi; Lu, Xing
• Is Part Of: Angewandte Chemie. Volume 128:Number 13(2016)
• Page Start: 4314
• Page End: 4318
• Publication Date: 2016-02-25
• Subjects: Dichtefunktionalrechnungen -- Endohedrale Fullerene -- Metall-Metall-Bindungen -- Radikalreaktionen -- Strukturaufklärung; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201511930
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Endohedral metallofullerenes (EMFs) have novel structures and properties that are closely associated with the internal metallic species. Benzyl radical additions have been previously shown to form closed‐shell adducts by attaching an odd number of addends to open‐shell EMFs (such as Sc3 C2 @ Ih ‐C80 ) whereas an even number of groups are added to closed‐shell EMFs (for example Sc3 N@ Ih ‐C80 ). Herein we report that benzyl radical addition to the closed‐shell La2 @ Ih ‐C80 forms a stable, open‐shell monoadduct instead of the anticipated closed‐shell bisadduct. Single‐crystal X‐ray diffraction results show the formation of a stable radical species. In this species, the La−La distance is comparable to the theoretical value of a La−La covalent bond and is shorter than reported values for other La2 @ Ih ‐C80 derivatives, providing unambiguous evidence for the formation of direct La−La bond.