Trifluoromethyl derivatives of insoluble small-HOMO-LUMO-gap hollow higher fullerenes. NMR and DFT structure elucidation of C2-(C74-D3h)(CF3)12, Cs-(C76-Td(2))(CF3)12, C2-(C78-D3h(5))(CF3)12, Cs-(C80-C2v(5))(CF3)12, and C2-(C82-C2(5))(CF3)12.
Reaction of a mixture of insoluble higher fullerenes with CF3I at 500 degrees C produced a single abundant isomer of C74(CF3)12, C76(CF3)12, and C80(CF3)12, two abundant isomers of C78(CF3)12 and C82(CF3)12, and an indeterminant number of isomers of C84(CF3)12. Using a combination of 19F NMR spectroscopy, DFT calculations, and the structures and spectra of previously reported fullerene(CF3)n compounds, the most-probable structures of six of the seven isolated compounds were determined to be specific isomers of C2-(C74-D3h)(CF3)12, Cs-(C76-Td(2))(CF3)12), C2-(C78-D3h(5))(CF3)12), Cs-(C80-C2v(5))(CF3)12), C2-(C82-C2(5))(CF3)12), and C2-(C82-C2(3))(CF3)12) containing ribbons and/or loops of edge-sharing para-C6(CF3)2 hexagons. The seventh isolated compound is a C1 isomer of C78(CF3)12 containing two such ribbons. This set of compounds represents only the second reported isolable compound with the hollow C74-D3h cage and the first experimental evidence for the existence of the hollow fullerenes C76-Td(2), C78-D3h(5), C80-C2v(5), and C82-C2(5) in arc-discharge soots.
Shustova
Natalia B
NB
Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA.
Kuvychko
Igor V
IV
Bolskar
Robert D
RD
Seppelt
Konrad
K
Strauss
Steven H
SH
Popov
Alexey A
AA
Boltalina
Olga V
OV
D000465:Algorithms; D002586:Cesium / Q000737:chemistry*; D005617:Chlorofluorocarbons, Methane / Q000737:chemistry*; D037741:Fullerenes / Q000737:chemistry*; D006846:Hydrocarbons, Halogenated / Q000737:chemistry*; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000737:chemistry*; D012995:Solubility; D013696:Temperature
D005617:Chlorofluorocarbons, Methane; D037741:Fullerenes; D006846:Hydrocarbons, Halogenated; D009942:Organometallic Compounds; D002586:Cesium; C105057:trifluoroiodomethane; C009554:fluoroform