Capturing the Unconventional Metallofullerene M@C-66 by Trifluoromethylation: A Theoretical Study
Capturing the Unconventional Metallofullerene M@C-66 by Trifluoromethylation: A Theoretical Study
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通过三氟甲基化捕获非常规金属富勒烯 M@C-66：理论研究
DOI：
10.1002/cphc.201700830
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发表时间：
2017
期刊：
影响因子：
2.9
通讯作者：
Shinohara Hisanori
中科院分区：
文献类型：
--
作者：
Xu Dan;Wang Zhiyong;Shinohara Hisanori
内嵌金属富勒烯M@C66（M=稀土金属）具有独特的结构，违反了富勒烯科学中众所周知的“孤立五边形规则”。虽然利用电弧放电法合成了M@C66has，但由于其自由基性质和极高的反应活性，对M@C66remain的溶剂提取和纯化提出了挑战。本文从理论上论证了通过c66笼的外面体功能化捕获这些缺失金属富勒烯的可能性。密度泛函理论计算揭示了Y@C66are稳定的三氟甲基化衍生物。单或多三氟甲基化Y@C66results在一个封闭的壳层电子构型和一个大的带隙。因此Y@C66can通过三氟甲基化大大稳定。三氟甲基倾向于附着在融合的五边形区域以减轻局部空间应变。研究了Y@C66(CF3)3的异构化机理，发现所附的三氟甲基可以通过过渡态从一个碳原子迁移到另一个碳原子上。
The endohedral metallofullerenes M@C66(M=rare‐earth metal) have a unique structure that violates the well‐known “isolated pentagon rule” of fullerene science. Although the synthesis of M@C66has been achieved by using the arc discharge method, the solvent extraction and purification of M@C66remain challenges because of their radical character and extremely high reactivity. In this paper, the possibility of capturing these missing metallofullerenes by exohedral functionalization of the C66cage is demonstrated theoretically. Stable trifluoromethylated derivatives of Y@C66are revealed by density functional theory calculations. Mono‐ or poly‐trifluoromethylation of Y@C66results in a closed‐shell electronic configuration and a large band gap. Thus Y@C66can be greatly stabilized through trifluoromethylation. The trifluoromethyl group prefers to be attached to the fused pentagon region to relieve local steric strain. The mechanism of isomerization of Y@C66(CF3)3is also investigated and it is found that the attached trifluoromethyl group can migrate from a carbon atom to another via a transition state.