Two Different Fullerenes Have the Same Cyclic Voltammetry

Journal of the American Chemical Society

Volumn 113, Issue 3, 1991, Pages 1050-1051

  Allemand, P M ^a   Koch, A ^a   Wudl, F ^a   Rubin, Y ^b   Diederich, F ^b   Alvarez, M M ^b   Anz, S J ^b   Whetten, R L ^b  

^a UNIVERSITY OF CALIFORNIA   (United States)

^b UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 84936500120     PISSN: 00027863     EISSN: 15205126     Source Type: Journal    
DOI: 10.1021/ja00003a053     Document Type: Article

References (13)

1. Krátschmer, W.; Lamb, L. D.; Fostiropoulos, K.; Huffman, D. R. Nature 1990, 347, 354.
2. Taylor, R.; Hare, J. P.; Abdul-Sada, A. K.; Kroto, H. W. J. Chem. Soc, Chem. Commun. 1990, 1423.
3. Ajie, H.; Alvarez, M. M.; Anz, S. J.; Beck, R. D.; Diederich, F.; Fostiropoulos, K.; Huffman, D. R.; Krátschmer, W.; Rubin, Y.; Schriver, K. E.; Sensharma, D.; Whetten, R. L. J. Phys. Chem., in press. The soluble extract (400 mg) of the soot resulting from resistive heating of graphite was adsorbed on 100 g of alumina and chromatographed on neutral alumina (activity 1; column dimensions: 8 × 60 cm). Hexane/toluene (95:5 v/v) elution afforded 250 mg of pure C60. Increasing the polarity to hexane/toluene (80:20 v/v) gave 50 mg of pure C70. The purity of C60 was established by comparison with previously reported spectral data.1,2 New characterization data are as follows: UV-visC60 [hexanes, 300 K, 2.47 × 10 and 1.235 × 10-5 M, λmax, (log ε)] 211 (5.17), 227 sh (4.91), 256 (5.24), 328 (4.71), 357 sh (4.08), 368 sh (3.91), 376 sh (3.75), 390 (3.52), 395 sh (3.30), 403 (3.48), 407 (3.28), 492 sh (2.72), 540 (2.85), 568 (2.78), 590 (2.86), 598 (2.87), 620 (2.60); UV-visc70 [hexanes, 300 K, 1.706 × 10-5 M, λmax, (log ε)] 214 (5.05), 235 (5.06), 249 sh (4.95), 268 sh (4.78), 313 (4.23), 330 (4.38), 359 (4.29), 377 (4.45), 468 (4.16), 542 (3.78), 590 sh (3.47), 599 sh (3.38), 609 (3.32), 623 sh (3.09), 635 sh (3.13), 646 sh (2.80); 13C NMR (see Figure 1).
4. Haufler, R. E.; Conceicao, J.; Chibante, L. P. F.; Chai, Y.; Byrne, N. E.; Flanagan, S.; Haley, M. M.; O’Brien, S. C.; Pan, C; Xiao, Z.; Billups, W. E.; Ciufolini, M. A.; Hauge, R. H.; Margrave, J. L.; Wilson, L. J.; Curl, R. F.; Smalley, R. E. J. Phys. Chem., in press.
5. Haddon, R. C.; Brus, L. E.; Raghavachari, K. Chem. Phys. Lett. 1986, 125, 459.
6. Gutmann, V. Coord. Chem. Rev. 1967, 2, 239.
7. Gutmann, V. Coordination Chemistry in Non-Aqueous Solutions, Springer-Verlag: Vienna and New York, 1968.
8. Haddon, R. C. (see ref 5, above), has stated that C60 fullerene is an aromatic compound, but no reference is made to the Hückel rule. The C60 would be a “4n” system, and addition of two electrons would make this a (4n + 2)π aromatic dianion.
9. Trost, B. M.; Bright, G. M.; Frihart, C; Brittelli, D. J. Am. Chem. Soc. 1971, 93, 737.
10. From mass spectrometric measurements, it was determined that C70 is 8 kcal/mol less stable than C60: Sharma, D. K., et al., in preparation.
11. Haddon et al. (Haddon, R. C.; Brus, L. E.; Raghavacharty, K. Chem. Phys. Lett. 1986, 131, 165) reported that C70 has a LUMO of ~0 × β.
12. If the Hückel rule would apply (see ref 8, above), then C70 would be a (4n + 2)π aromatic molecule.
13. Dr. R. C. Haddon has pointed out that what we have termed strain may be the same as his interpretation of bonding in the fullerenes in terms of rehybridization (Haddon, R. C. Acc. Chem. Res. 1988, 21, 243). The higher s character of the bonding system (s0.093p) makes it more electronegative.