Kein C₅Me₅⁺ (II): Die Suche nach dem schwer fassbaren Singulett-Pentamethylcyclopentadienyl-Kation muss weiter gehen. Quantenmechanischen Berechnungen sowohl der Strukturdaten als auch der chemischen Verschiebungen im NMR-Spektrum zufolge, handelt es sich bei einer kürzlich beschriebenen Röntgenkristallstruktur nicht um das vermeintliche C₅Me₅⁺-Ion, sondern um das Pentamethylcyclopentenyl-Kation (siehe Bild).

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References

1 J. B. Lambert, L. Lin, V. Rassolov, Angew. Chem. 2002, 114, 1487;
10.1002/1521-3757(20020415)114:8<1487::AID-ANGE1487>3.0.CO;2-3
Google Scholar
Angew. Chem. Int. Ed. 2002, 41, 1429.
10.1002/1521-3773(20020415)41:8<1429::AID-ANIE1429>3.0.CO;2-J
CAS PubMed Web of Science® Google Scholar
2 Geometrical data are extracted from the Cambridge data base file CCDC-178042.
Google Scholar
3
Google Scholar
3a A detailed review is given by V. I. Minkin, M. N. Glukhovtsev, B. Y. Simkin, Aromaticity and Antiaromaticity, Wiley, New York, 1994, p. 230;
Google Scholar
3b M. N. Glukhovtsev, B. Reindl, P. v. R. Schleyer Mendeleev Commun. 1993, 100;
10.1070/MC1993v003n03ABEH000242
CAS Web of Science® Google Scholar
3c B. Reindl, P. v. R. Schleyer, J. Comput. Chem. 1998, 19, 1402;
10.1002/(SICI)1096-987X(199809)19:12<1402::AID-JCC7>3.0.CO;2-M
CAS Web of Science® Google Scholar
3d Y. Shiota, M. Kondo, K. Yoshizawa, J. Chem. Phys. 2001, 115, 9243;
10.1063/1.1412250
CAS Web of Science® Google Scholar
3e The triplet state, 1(T), is however lower in energy than 1 b by 6.1 kcal mol⁻¹ (B3LYP/6–31G(d)).
Google Scholar
4 ¹³C NMR data for allyl cations:
Google Scholar
4a G. A. Olah, G. Liang, J. Am. Chem. Soc. 1972, 94, 8071;
Web of Science® Google Scholar
4b H. Mayr, G. A. Olah, J. Am. Chem. Soc. 1977, 99, 510;
10.1021/ja00444a032
CAS Web of Science® Google Scholar
4c G. A. Olah, H. Mayr, J. Am. Chem. Soc. 1976, 98, 7333;
10.1021/ja00439a600
Web of Science® Google Scholar
4d G. A. Olah, P. R. Clifford, Y. Halpern, R. G. Johanson, J. Am. Chem. Soc. 1971, 93, 4219;
10.1021/ja00746a022
CAS Web of Science® Google Scholar
4e G. A. Olah, R. J. Spear, J. Am. Chem. Soc. 1975, 97, 1539.
10.1021/ja00839a044
CAS Web of Science® Google Scholar
5 All calculations were performed with Gaussian 98 Revisions A3–A9, Gaussian, Inc., M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, V. G. Zakrzewski, J. A. Montgomery, R. E. Stratmann, J. C. Burant, S. Dapprich, J. M. Millam, A. D. Daniels, K. N. Kudin, M. C. Strain, O. Farkas, J. Tomasi, V. Barone, M. Cossi, R. Cammi, B. Mennucci, C. Pomelli, C. Adamo, S. Clifford, J. Ochterski, G. A. Petersson, P. Y. Ayala, Q. Cui, K. Morokuma, D. K. Malick, A. D. Rabuck, K. Raghavachari, J. B. Foresman, J. Cioslowski, J. V. Ortiz, A. G. Baboul, B. B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. Gomperts, R. L. Martin, D. J. Fox, T. Keith, M. A. Al-Laham, C. Y. Peng, A. Nanayakkara, C. Gonzalez, M. Challacombe, P. M. W. Gill, B. G. Johnson, W. Chen, M. W. Wong, J. L. Andres, M. Head-Gordon, E. S. Replogle, J. A. Pople, Gaussian, Inc., Pittsburgh, PA, 1999.
Google Scholar
6
Google Scholar
6a A. D. Becke, Phys. Rev. A 1988, 38, 3098;
10.1103/PhysRevA.38.3098
CAS Web of Science® Google Scholar
6b A. D. Becke, J. Chem. Phys. 1993, 98, 5648;
10.1063/1.464913
CAS Web of Science® Google Scholar
6c C. Lee, W. Yang, R. G. Parr, Phys. Rev. B. 1988, 37, 785.
10.1103/PhysRevB.37.785
CAS PubMed Web of Science® Google Scholar
7
Google Scholar
7a R. Ditchfield, Mol. Phys. 1974, 27, 789;
10.1080/00268977400100711
CAS Web of Science® Google Scholar
7b K. Wolinski, J. F. Hilton, P. Pulay, J. Am. Chem. Soc. 1982, 104, 5667;
10.1021/ja00385a019
Web of Science® Google Scholar
7c J. R. Cheeseman, G. W. Trucks, T. A. Keith, M. J. Frisch, J. Chem. Phys. 1996, 104, 5497.
10.1063/1.471789
CAS Web of Science® Google Scholar
8 For an introduction in the methodology see: W. J. Hehre, L. Radom, P. v. R. Schleyer, J. A. Pople, Ab initio molecular orbital theory, Wiley, New York, 1986.
10.1021/ja00267a063
CAS Google Scholar
9 Calculated from single-point energies using the heavy-atom geometry of 1 a with all 15 hydrogen positions of 1 optimized at B3LYP/6–31G(d).
Google Scholar
10 Calculated by using the heavy-atom geometry of 1 a with all 17 hydrogen positions of 2 optimized at B3LYP/6–31G(d).
Google Scholar

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