Isolation and Structural Characterization of a Family of Endohedral Fullerenes Including the Large, Chiral Cage Fullerenes Tb3N@C88 and Tb3N@C86 as well as

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• 作者：Tianming Zuo ; Christine M. Beavers ; James C. Duchamp ; Anne Campbell ; Harry C. Dorn ; Marilyn M. Olmstead ; Alan L. Balch
• 刊名：Journal of the American Chemical Society
• 出版年：2007
• 出版时间：February 21, 2007
• 年：2007
• 卷：129
• 期：7
• 页码：2035 - 2043
• 全文大小：1349K
• 年卷期：v.129,no.7(February 21, 2007)
• ISSN：1520-5126

文摘

The recent finding that isomer 2 of Tb₃N@C₈₄ uses one of the 51 568 possible nonisolatedpentagon rule (non-IPR) structures for the C₈₄ cage rather than one of the 24 cage isomers that do obeythe IPR suggests that further experimental work on the structure of larger endohedrals is needed to observethe utility of the IPR rule in this uncharted territory. The structures of the newly synthesized endohedralfullerenes-Tb₃N@C₈₈, Tb₃N@C₈₆, and the I_h and D_5h isomers of Tb₃N@C₈₀- have been determined bysingle-crystal X-ray diffraction on samples cocrystallized with Ni^II(octaethylporphyrin). In contrast to thesituation for isomer 2 of Tb₃N@C₈₄, the structures of Tb₃N@C₈₈ and Tb₃N@C₈₆ do conform to the IPR.Both Tb₃N@C₈₈ and Tb₃N@C₈₆ have chiral structures with D₂ symmetry for Tb₃N@C₈₈ and D₃ symmetryfor Tb₃N@C₈₆. Within this group of endohedrals, the size of the carbon cage affects the Tb-N and Tb-Cdistances, the orientations of the carbon cage with respect to the porphyrin plane, the locations of themetal ions and their orientations relative to the porphyrin plane, and the degree of pyramidalization of theTb₃N unit.