Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, Synergetic Innovation Center of Quantum Information & Quantum Physics , University of Science and Technology of China , Hefei 230026 , China.
Department of Chemistry , Moscow State University , 119991 Moscow, Leninskie gory , Russia.
J Am Chem Soc. 2018 Mar 14;140(10):3496-3499. doi: 10.1021/jacs.7b12925. Epub 2018 Feb 5.
As one of the largest sub-branches of endohedral clusterfullerenes, dimetal carbide clusterfullerene (CCF) in the form of MC@C is quite intriguing since an alternative structure of M@C as conventional dimetallofullerene may exist as well. Herein, by using high-temperature trifluoromethylation followed by HPLC separation and single-crystal X-ray diffraction study, we report for the first time the unambiguous structural determination of yttrium (Y)-based CCF as its trifluoromethyl derivatives, YC@C(6)(CF). Four isomers of YC@C(6)(CF) with different addition patterns of 16 CF groups are successfully isolated, and two Y atoms of the butterfly-shaped YC cluster are coordinated by two cage pentagons in each isomer. The butterfly geometry of YC cluster varies significantly in the four YC@C(6)(CF) isomers, with Y···Y distances ranging from 3.544 to 4.051 Å dependent on the relative positions of the two yttrium-coordinated pentagons on the carbon cage.
作为内包金属富勒烯的最大亚分支之一，以 MC@C 形式存在的二碳化金属团簇富勒烯（CCF）非常有趣，因为可能也存在 M@C 作为传统双金属富勒烯的替代结构。在此，我们通过使用高温三氟甲基化，然后通过 HPLC 分离和单晶 X 射线衍射研究，首次明确地确定了 Y 基 CCF 作为其三氟甲基衍生物 YC@C(6)(CF)的结构。成功分离出具有不同 16 个 CF 基团加成模式的 4 种 YC@C(6)(CF)异构体，并且蝶形 YC 团簇的两个 Y 原子在每个异构体中均由两个笼五边形配位。在这 4 种 YC@C(6)(CF)异构体中，YC 团簇的蝶形几何形状变化很大，Y···Y 距离范围为 3.544 至 4.051 Å，取决于两个 Y 配位五边形在碳笼上的相对位置。
