Xie Suyuan, Zhang Qianyan, Xiamen University and Yang Shangfeng, University of science and technology of China, jointly developed the "hand" of decapyrrolidovalene molecule for the immobilization of fullerenes

Recently, Xie Suyuan and Zhang Qianyan of School of chemistry and chemical engineering of Xiamen University cooperated with Yang Shangfeng of University of science and technology of China to make progress in the accurate characterization of new fullerenes Relevant research results were published in nature communications (DOI: 10.1038 / s41467-019-08343-6) under the title of "flexible decapyrrylorannulene hosts" Spherical cage like fullerenes are one of the most important scientific discoveries at the end of last century, but it is difficult to understand the exact geometry of fullerenes The reason is that the orientation of spherical molecules in single crystals is often disordered, which needs to be derived from the cage or through octaethyl metalloporphyrins- The orientation of fullerenes is fixed by the host guest assembly of fullerenes, and then the geometry of fullerenes is accurately characterized by the commonly used single crystal diffraction analysis technology However, many new structures of fullerenes can not form high-quality single crystals with porphyrin as the main body, so far, X-ray diffraction technology can not be used for structural analysis, which directly restricts the in-depth understanding of the formation mechanism of fullerenes and the structure performance relationship In this study, the author explored a new way to synthesize the decadiene molecule C20 (c4h4n) 10, which was substituted by decapyrrole The results of structural analysis show that the structure of the molecule is characterized by that the carbon framework of the cuprene is connected with ten pyrrole groups by a single bond, and the dihedral angles formed between each pyrrole plane and the cuprene can be adjusted by the rotation of the single bond, which is similar to the chiral molecular "hand": the cuprene framework with curved surface structure is similar to the "hand", The pyrrole group which can adjust dihedral angle adaptively is similar to "finger" The author assembled the decapyrrolidowanene with 15 different fullerenes, and proved that the decapyrrolidowanene can be separated from empty cage fullerenes, embedded fullerenes, cage derived fullerenes, fullerene dimers, Heterofullerenes, and non IPR with adjacent five rings, which violates the isolated pentagon rule (IPR) Fullerenes) and other known fullerenes can be assembled to form ordered two-dimensional single crystals of fullerene assembly structure, and they all adopt the "left-handed carbon cage right-handed" host object assembly mode, which is similar to the way we used to hold the ball with both hands The single crystal is suitable for X-ray single crystal diffraction analysis, which solves the problem of precise characterization of some unsolved fullerenes The experimental results also show that the hydrogen in the 3,4-position of pyrrole substituted by methyl is not conducive to the formation of ordered supramolecular assembly of fullerene and cuprene derivatives, which shows that the "clean" pyrrole "finger" has specificity The theoretical study further explains the reason why the collective contribution of ten pyrrole "fingers" is greater than that of a single cuprene "palm" This work involves the structural characterization of 15 representative fullerenes, 10 of which have never been reported in the past Professor Yang Shangfeng from China University of science and technology provided two samples of embedded fullerenes (SC 3N @ C80) and high fullerenes (C90) Xu Yunyan (2014 master's degree), Tian Hanrui (2014 doctor's degree) and Li Shuhui (2016 entry post doctor) are the co first authors of this paper The research work was supported by NSFC (21771152, 21721001, 21827801, 51572231, 51572254, 21571151, 2170010228), Ministry of science and technology 973 Plan (2014cb845601, 2015cb932301), key research and development plan (2017yfa0402800), National Postdoctoral Science Fund, basic research business fees of Central University, etc.