Synthesis, Separation And Chemical Properties Of Embedded Yttrium Metal Fullerenes

With the development of science,some new carbon allotropes have been discovered,such as fullerenes,graphene and so on.And the internal space of fullerenes are kinds of special cavity containing atoms,ions or clusters.So the physicochemical properties,electronic properties,geometric structures of fullerenes are different with hollow fullerenes.It is noteworthy that due to its novel structure and unique properties,the endoheral metallofullerene has broad application in many high-tech fields such as optics,magnetism,molecular electronic devices and biomedical engineering.This study mainly includes the following aspects:1.The soot containing yttrium fullerene was prepared by direct current arc discharge,and extracted by carbon disulfide.Then,the metallofullerenes were separated and purified by high performance liquid chromatography?HPLC?.Finally,samples of highly pure Y@C_s-C₈₂,Y₂@C_3v-C_82,and Y₂C₉₆ were obtained.And these samples were charaterized by laser desorption/ionization time of flight mass spectrometry?LDI-TOF-Ms?and Vis-NIR spectroscopy.2.The chemical properties were explored by two 1,3-dipolar reactions of Y₂@C_3v-C₈₂ or C₆₀.In this paper,the corresponding two stable fullerene derivatives,Y₂@C_3v-C₈₂(C₁₃N₂H₁₀)?2a?or C₆₀(C₁₃N₂H₁₀)?2b?,were obtained by the high selective reaction of Y₂@C_3v-C₈₂ or C₆₀0 with Diphenylnitrilimine?DPNI?.Then,continuing to utilize the highly selective reaction of Y₂@C_3v-C₈₂ or C₆₀ with N-methoxymethyl-N-?trimethylsilyl?benzylamine?SMBA?gave the corresponding two stable fullerenes derivatives Y₂@C_3v-C₈₂(C₉NH₁₁)?4a?or C₆₀(C₉NH₁₁)?4b?.And structures and properties of these derivatives were characterized.Vis-NIR results show that two reactions all changed electronic structure of Y₂@C_3v-C₈₂(C₆₀);and also have a significant impact on the electronic structure of Y₂@C_3v-C₈₂(C₆₀).X-ray crystallographic results reveal that the addition position of Y₂@C_3v-C₈₂(C₆₀)derivatives are all at[6,6]-bond;3.Through the reaction of Y@C_s-C₈₂ and diethyl bromomalonate catalyzed by DBU,a stable fullerene derivative Y@C_s-C₈₂(C₇H₁₁O₄Br)was obtained and its structure and properties were studied Characterization.X-ray crystallographic results reveal that the derivatives of Y@C_s-C₈₂ were single-bond additions and the addition sites were at the apexes of two six-membered rings and one five-membered ring;the absorption spectrum test results showed that the reaction remarkably changed Y@C_s-C₈₂ electronic structure;...