Preparation Of Indole Metal Fullerene And Chemical Functionalization Of Tb@C 82

There are many carbon allotropes,and fullerene is the only one in molecular formation.Fullerenes are molecules with ball,elliptical,or tubular hollow interior spaces.When metal atoms or metal clusters are embedded into the hollow interior spaces,endohedral metallofullerene（EMFs）are formed.EMFs have the properties of both fullerenes and embedded metal atoms or metal clusters,which are expected to be of excellent electronic,magnetic and optical properties.Owing to the charge transfer from embedded metal atoms or metal clusters to carbon cage,EMFs have some advantages over empty fullerenes and thus are applicable in many fields.In this thesis,soot containing terbium EMFs was synthesized in a modified Kr?tschmer-Huffman generator by vaporizing the composite graphite rods of Tb₄O₇ and graphite powder at an atmosphere of 300 torr He.The as-produced soot was collected and refluxed in 1,2,4-trichlorobenzene（TCB）for 12 h.After filtration and distillation to remove TCB,the product was immediately dissolved in toluene,and then subjected to preparative HPLC isolation.A series of terbium EMFs including TbC₈₂（I,II）,Tb₂C₈₄（I,II）,Tb₂C₉₀（I,II）and Tb₂C₉₂2 were successfully isolated,and their purity was confirmed by matrix-assisted laser desorption time-of-flight（MALD-TOF）mass spectrometry and analytical HPLC.UV-vis-NIR absorption spectroscopy was applied to the characterization of the above isolated terbium EMFs,and the molecular structures of TbC₈₂（I）,TbC₈₂（II）,Tb₂C₈₄（I）,Tb₂C₈₄（II）and Tb₂C₉₀（II）were assigned to Tb@C_2v-C₈₂,Tb@C_s-C₈₂,Tb₂C₂@C_2v-C₈₂,Tb₂C₂@C_3v-C₈₂2 and Tb₂C₂@C_s（hept）-C₈₈,respectively.The electrochemical properties of Tb₂C₉₀（I,II）isomers were investigated by cyclic voltammetry.It is found that the first reduction of Tb₂C₉₀（II）was close to that of Tb₂C₉₀（I）,whereas its first oxidation potential was larger than that of Tb₂C₉₀（I）.Hence,Tb₂C₉₀（II）was a better electron acceptor than Tb₂C₉₀（I）.Through comparative study of Tb₂C₂@C_s（hept）-C₈₈8 and Sc₂C₂@C_s（hept）-C₈₈,it was concluded that the endohedral dimetallo-carbide cluster had greater effect on the oxidation properties than reduction properties of dimetallo-carbide clusterfullerenes.And glycine and2,5-dimethoxy-4-pyridin-4-yl-[1,1-biphenyl]-4-carbaldehyde were applied to the Prato reaction with Tb@C₈₂（I）,and two mono-adducts were detected,proving that this reaction is of good selectivity even though it is reversible.