Hyperconjugative π-aromaticity: How to make cyclopentadiene aromatic

Journal of the American Chemical Society

Volumn 121, Issue 29, 1999, Pages 6872-6875

  Nyulászi, László ^a,b,d   Von Ragué Schleyer, Paul ^b,c  

^a Rheinland Pfälzische Technische Universität Kaiserslautern Landau   (Germany)

^b UNIVERSITY OF ERLANGEN NUREMBERG   (Germany)

^c UNIVERSITY OF GEORGIA   (United States)

^d BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS   (Hungary)

Author keywords

[No Author keywords available]

Indexed keywords

AROMATIC COMPOUND; CYCLOPENTADIENE DERIVATIVE; FURAN;

ARTICLE; CHEMICAL ANALYSIS; CHEMICAL MODIFICATION; CHEMICAL REACTION; CHEMICAL STRUCTURE; CONJUGATION; MOLECULAR DYNAMICS; MOLECULAR STABILITY; STRUCTURE ACTIVITY RELATION;

EID: 0344631650     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja983113f     Document Type: Article

References (45)

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2. See, e.g.: Minkin, V. I.; Glukhotsev, M. N.; Simkin, B. Ya. Aromaticity and Antiaromaticity. Electronic and Structural Aspects; John Wiley & Sons: New York, 1994. Schleyer, P. v. R.; Jiao, H. Pure Appl. Chem. 1996, 68, 209.
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4. Mulliken R. S.; Rieke, C. A.; Brown, W. G. J. Am. Chem. Soc. 1941, 63, 41. Dauben, H. J., Jr.; Wilson, J. D.; Laity, J. L. J. Am. Chem. Soc. 1968, 91, 811. Dauben, H. J., Jr.; Wilson, J. D.; Laity, J. L. J. Am. Chem. Soc. 1968, 91, 1911. Dauben, H. J., Jr.; Wilson, J. D.; Laity, J, L. In Nonbenzoid Aromatics; Synder, J. P., Ed.; Academic Press: New York, 1971; Vol. II, pp 167-206. Labarre, J.-F.; Crasnier, F. Top. Curr. Chem. 1971, 24, 33. Haddon, R. C.; Haddon, V. R.; Jackman, L. M. Top. Curr. Chem. 1971, 16, 112.
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8. Mulliken R. S.; Rieke, C. A.; Brown, W. G. J. Am. Chem. Soc. 1941, 63, 41. Dauben, H. J., Jr.; Wilson, J. D.; Laity, J. L. J. Am. Chem. Soc. 1968, 91, 811. Dauben, H. J., Jr.; Wilson, J. D.; Laity, J. L. J. Am. Chem. Soc. 1968, 91, 1911. Dauben, H. J., Jr.; Wilson, J. D.; Laity, J, L. In Nonbenzoid Aromatics; Synder, J. P., Ed.; Academic Press: New York, 1971; Vol. II, pp 167-206. Labarre, J.-F.; Crasnier, F. Top. Curr. Chem. 1971, 24, 33. Haddon, R. C.; Haddon, V. R.; Jackman, L. M. Top. Curr. Chem. 1971, 16, 112.
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18. This "β-silyl effect" has been discussed extensively in carbocations; see, e.g.: Sommer, L. H.; Dorfmann, E.; Goldberg, L. M.; Whitmore, F. C. J. Am. Chem. Soc. 1946, 68, 488. Ibrahim, M. R.; Jorgensen, W. L. J. Am. Chem. Soc. 1989, 111, 819. Even a stable β-silyl carbocation was reported: Lambert, J. B.; Zhao, Y. J. Am. Chem. Soc. 1996, 118, 7867 and references therein. Mayr, H.; Basso, N. Angew. Chem. 1992, 104, 1103. Maerker, C.; Schleyer, P. v. R. Silicenium ions: Quantum Chemical Computations. In The Chemistry of Organosilicon Compounds, Vol. 2; Rappoport, Z., Apeloig, Y., Eds.; John Wiley: New York, 1998. Apeloig, Y.; Müller, T. In Theory and Calculations in Dicoordinated Carbocations; Rappoport, Z., Stang, P. J., Eds.; John Wiley: Chichester, 1997.
19. This "β-silyl effect" has been discussed extensively in carbocations; see, e.g.: Sommer, L. H.; Dorfmann, E.; Goldberg, L. M.; Whitmore, F. C. J. Am. Chem. Soc. 1946, 68, 488. Ibrahim, M. R.; Jorgensen, W. L. J. Am. Chem. Soc. 1989, 111, 819. Even a stable β-silyl carbocation was reported: Lambert, J. B.; Zhao, Y. J. Am. Chem. Soc. 1996, 118, 7867 and references therein. Mayr, H.; Basso, N. Angew. Chem. 1992, 104, 1103. Maerker, C.; Schleyer, P. v. R. Silicenium ions: Quantum Chemical Computations. In The Chemistry of Organosilicon Compounds, Vol. 2; Rappoport, Z., Apeloig, Y., Eds.; John Wiley: New York, 1998. Apeloig, Y.; Müller, T. In Theory and Calculations in Dicoordinated Carbocations; Rappoport, Z., Stang, P. J., Eds.; John Wiley: Chichester, 1997.
20. This "β-silyl effect" has been discussed extensively in carbocations; see, e.g.: Sommer, L. H.; Dorfmann, E.; Goldberg, L. M.; Whitmore, F. C. J. Am. Chem. Soc. 1946, 68, 488. Ibrahim, M. R.; Jorgensen, W. L. J. Am. Chem. Soc. 1989, 111, 819. Even a stable β-silyl carbocation was reported: Lambert, J. B.; Zhao, Y. J. Am. Chem. Soc. 1996, 118, 7867 and references therein. Mayr, H.; Basso, N. Angew. Chem. 1992, 104, 1103. Maerker, C.; Schleyer, P. v. R. Silicenium ions: Quantum Chemical Computations. In The Chemistry of Organosilicon Compounds, Vol. 2; Rappoport, Z., Apeloig, Y., Eds.; John Wiley: New York, 1998. Apeloig, Y.; Müller, T. In Theory and Calculations in Dicoordinated Carbocations; Rappoport, Z., Stang, P. J., Eds.; John Wiley: Chichester, 1997.
21. This "β-silyl effect" has been discussed extensively in carbocations; see, e.g.: Sommer, L. H.; Dorfmann, E.; Goldberg, L. M.; Whitmore, F. C. J. Am. Chem. Soc. 1946, 68, 488. Ibrahim, M. R.; Jorgensen, W. L. J. Am. Chem. Soc. 1989, 111, 819. Even a stable β-silyl carbocation was reported: Lambert, J. B.; Zhao, Y. J. Am. Chem. Soc. 1996, 118, 7867 and references therein. Mayr, H.; Basso, N. Angew. Chem. 1992, 104, 1103. Maerker, C.; Schleyer, P. v. R. Silicenium ions: Quantum Chemical Computations. In The Chemistry of Organosilicon Compounds, Vol. 2; Rappoport, Z., Apeloig, Y., Eds.; John Wiley: New York, 1998. Apeloig, Y.; Müller, T. In Theory and Calculations in Dicoordinated Carbocations; Rappoport, Z., Stang, P. J., Eds.; John Wiley: Chichester, 1997.
22. This "β-silyl effect" has been discussed extensively in carbocations; see, e.g.: Sommer, L. H.; Dorfmann, E.; Goldberg, L. M.; Whitmore, F. C. J. Am. Chem. Soc. 1946, 68, 488. Ibrahim, M. R.; Jorgensen, W. L. J. Am. Chem. Soc. 1989, 111, 819. Even a stable β-silyl carbocation was reported: Lambert, J. B.; Zhao, Y. J. Am. Chem. Soc. 1996, 118, 7867 and references therein. Mayr, H.; Basso, N. Angew. Chem. 1992, 104, 1103. Maerker, C.; Schleyer, P. v. R. Silicenium ions: Quantum Chemical Computations. In The Chemistry of Organosilicon Compounds, Vol. 2; Rappoport, Z., Apeloig, Y., Eds.; John Wiley: New York, 1998. Apeloig, Y.; Müller, T. In Theory and Calculations in Dicoordinated Carbocations; Rappoport, Z., Stang, P. J., Eds.; John Wiley: Chichester, 1997.
23. This "β-silyl effect" has been discussed extensively in carbocations; see, e.g.: Sommer, L. H.; Dorfmann, E.; Goldberg, L. M.; Whitmore, F. C. J. Am. Chem. Soc. 1946, 68, 488. Ibrahim, M. R.; Jorgensen, W. L. J. Am. Chem. Soc. 1989, 111, 819. Even a stable β-silyl carbocation was reported: Lambert, J. B.; Zhao, Y. J. Am. Chem. Soc. 1996, 118, 7867 and references therein. Mayr, H.; Basso, N. Angew. Chem. 1992, 104, 1103. Maerker, C.; Schleyer, P. v. R. Silicenium ions: Quantum Chemical Computations. In The Chemistry of Organosilicon Compounds, Vol. 2; Rappoport, Z., Apeloig, Y., Eds.; John Wiley: New York, 1998. Apeloig, Y.; Müller, T. In Theory and Calculations in Dicoordinated Carbocations; Rappoport, Z., Stang, P. J., Eds.; John Wiley: Chichester, 1997.
24. Shimizu, H.; Gordon, M. S. Organometallics 1994, 13, 186.
25. Bock, H.; Solouki, B. Photoelectron Spectra of Silicon Compounds. In The Chemistry of Silicon Compounds; Patai, S., Rappaport, Z., Eds.; J. Wiley: Chichester, 1989. Nyulászi, L.; Veszprémi, T.; Réffy, J. J. Organomet. Chem. 1993, 445, 29.
26. Bock, H.; Solouki, B. Photoelectron Spectra of Silicon Compounds. In The Chemistry of Silicon Compounds; Patai, S., Rappaport, Z., Eds.; J. Wiley: Chichester, 1989. Nyulászi, L.; Veszprémi, T.; Réffy, J. J. Organomet. Chem. 1993, 445, 29.
27. Calculations were performed with the Gaussian 94 program package (Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head-Gordon, M.; Gonzalez, C.; Pople, J. A. Gaussian 94, Revision E.2; Gaussian, Inc.: Pittsburgh, PA, 1995). Geometries were optimized at the B3LYP/6- 311+G** (see also note 15) and B3LYP/3-21G(*) levels, resulting in similar structures. The NMR shielding tensors (in ppm) were calculated by the GIAO scheme; diamagnetic susceptibilities (in ppm) were calculated by the IGAIM method with the 6-311+G** basis at the B3LYP/6-311+G**. optimized geometries and with the 3-21G(*) basis at the B3LYP/3-21G(*) geometries. Second derivatives were calculated at the optimized structures at both B3LYP/3-21G(*) and the B3LYP/6-311+G** levels. SOS-DFT routines (Malkin, V. G.; Malkina, O. L.; Salahub, D. R. Chem. Phys. Lett. 1993, 204, 80) of the DeMon program package (Malkin, V. G.; Malkina, O. L.; Casida, M. E.; Salahub, D. R. J. Am. Chem. Soc. 1994, 116, 5898) were used with the BIII basis set (Kutzelnigg, W.; Fleischer, U.; Schindler, M. NMR Basic Princ. Prog. 1990, 23, 190) to compute the individual localized molecular orbital contributions to the NICS value by employing the Pipek-Mezey localization (Pipek, J.; Mezey, P. G. Chem. Phys. 1989, 90, 4916), which separates σ- and π-components of the double bonds; see also ref 18. Diamagnetic susceptibilities, calculated NMR chemical shifts on the β carbon atom, and total energies are given as Supporting Information.
28. Calculations were performed with the Gaussian 94 program package (Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head- Gordon, M.; Gonzalez, C.; Pople, J. A. Gaussian 94, Revision E.2; Gaussian, Inc.: Pittsburgh, PA, 1995). Geometries were optimized at the B3LYP/6-311+G** (see also note 15) and B3LYP/3-21G(*) levels, resulting in similar structures. The NMR shielding tensors (in ppm) were calculated by the GIAO scheme; diamagnetic susceptibilities (in ppm) were calculated by the IGAIM method with the 6-311+G** basis at the B3LYP/6-311+G**. optimized geometries and with the 3-21G(*) basis at the B3LYP/3-21G(*) geometries. Second derivatives were calculated at the optimized structures at both B3LYP/3-21G(*) and the B3LYP/6-311+G** levels. SOS-DFT routines (Malkin, V. G.; Malkina, O. L.; Salahub, D. R. Chem. Phys. Lett. 1993, 204, 80) of the DeMon program package (Malkin, V. G.; Malkina, O. L.; Casida, M. E.; Salahub, D. R. J. Am. Chem. Soc. 1994, 116, 5898) were used with the BIII basis set (Kutzelnigg, W.; Fleischer, U.; Schindler, M. NMR Basic Princ. Prog. 1990, 23, 190) to compute the individual localized molecular orbital contributions to the NICS value by employing the Pipek-Mezey localization (Pipek, J.; Mezey, P. G. Chem. Phys. 1989, 90, 4916), which separates σ- and π-components of the double bonds; see also ref 18. Diamagnetic susceptibilities, calculated NMR chemical shifts on the β carbon atom, and total energies are given as Supporting Information.
29. Calculations were performed with the Gaussian 94 program package (Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head- Gordon, M.; Gonzalez, C.; Pople, J. A. Gaussian 94, Revision E.2; Gaussian, Inc.: Pittsburgh, PA, 1995). Geometries were optimized at the B3LYP/6- 311+G** (see also note 15) and B3LYP/3-21G(*) levels, resulting in similar structures. The NMR shielding tensors (in ppm) were calculated by the GIAO scheme; diamagnetic susceptibilities (in ppm) were calculated by the IGAIM method with the 6-311+G** basis at the B3LYP/6-311+G**. optimized geometries and with the 3-21G(*) basis at the B3LYP/3-21G(*) geometries. Second derivatives were calculated at the optimized structures at both B3LYP/3-21G(*) and the B3LYP/6-311+G** levels. SOS-DFT routines (Malkin, V. G.; Malkina, O. L.; Salahub, D. R. Chem. Phys. Lett. 1993, 204, 80) of the DeMon program package (Malkin, V. G.; Malkina, O. L.; Casida, M. E.; Salahub, D. R. J. Am. Chem. Soc. 1994, 116, 5898) were used with the BIII basis set (Kutzelnigg, W.; Fleischer, U.; Schindler, M. NMR Basic Princ. Prog. 1990, 23, 190) to compute the individual localized molecular orbital contributions to the NICS value by employing the Pipek-Mezey localization (Pipek, J.; Mezey, P. G. Chem. Phys. 1989, 90, 4916), which separates σ- and π-components of the double bonds; see also ref 18. Diamagnetic susceptibilities, calculated NMR chemical shifts on the β carbon atom, and total energies are given as Supporting Information.
30. Calculations were performed with the Gaussian 94 program package (Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head- Gordon, M.; Gonzalez, C.; Pople, J. A. Gaussian 94, Revision E.2; Gaussian, Inc.: Pittsburgh, PA, 1995). Geometries were optimized at the B3LYP/6- 311+G** (see also note 15) and B3LYP/3-21G(*) levels, resulting in similar structures. The NMR shielding tensors (in ppm) were calculated by the GIAO scheme; diamagnetic susceptibilities (in ppm) were calculated by the IGAIM method with the 6-311+G** basis at the B3LYP/6-311+G**. optimized geometries and with the 3-21G(*) basis at the B3LYP/3-21G(*) geometries. Second derivatives were calculated at the optimized structures at both B3LYP/3-21G(*) and the B3LYP/6-311+G** levels. SOS-DFT routines (Malkin, V. G.; Malkina, O. L.; Salahub, D. R. Chem. Phys. Lett. 1993, 204, 80) of the DeMon program package (Malkin, V. G.; Malkina, O. L.; Casida, M. E.; Salahub, D. R. J. Am. Chem. Soc. 1994, 116, 5898) were used with the BIII basis set (Kutzelnigg, W.; Fleischer, U.; Schindler, M. NMR Basic Princ. Prog. 1990, 23, 190) to compute the individual localized molecular orbital contributions to the NICS value by employing the Pipek-Mezey localization (Pipek, J.; Mezey, P. G. Chem. Phys. 1989, 90, 4916), which separates σ- and π-components of the double bonds; see also ref 18. Diamagnetic susceptibilities, calculated NMR chemical shifts on the β carbon atom, and total energies are given as Supporting Information.
31. Calculations were performed with the Gaussian 94 program package (Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head- Gordon, M.; Gonzalez, C.; Pople, J. A. Gaussian 94, Revision E.2; Gaussian, Inc.: Pittsburgh, PA, 1995). Geometries were optimized at the B3LYP/6- 311+G** (see also note 15) and B3LYP/3-21G(*) levels, resulting in similar structures. The NMR shielding tensors (in ppm) were calculated by the GIAO scheme; diamagnetic susceptibilities (in ppm) were calculated by the IGAIM method with the 6-311+G** basis at the B3LYP/6-311+G**. optimized geometries and with the 3-21G(*) basis at the B3LYP/3-21G(*) geometries. Second derivatives were calculated at the optimized structures at both B3LYP/3-21G(*) and the B3LYP/6-311+G** levels. SOS-DFT routines (Malkin, V. G.; Malkina, O. L.; Salahub, D. R. Chem. Phys. Lett. 1993, 204, 80) of the DeMon program package (Malkin, V. G.; Malkina, O. L.; Casida, M. E.; Salahub, D. R. J. Am. Chem. Soc. 1994, 116, 5898) were used with the BIII basis set (Kutzelnigg, W.; Fleischer, U.; Schindler, M. NMR Basic Princ. Prog. 1990, 23, 190) to compute the individual localized molecular orbital contributions to the NICS value by employing the Pipek-Mezey localization (Pipek, J.; Mezey, P. G. Chem. Phys. 1989, 90, 4916), which separates σ- and π-components of the double bonds; see also ref 18. Diamagnetic susceptibilities, calculated NMR chemical shifts on the β carbon atom, and total energies are given as Supporting Information.
32. Sieber et al. (Sieber, S.; Schleyer, P. v. R.; Gauss, J. J. Am. Chem. Soc. 1993, 115, 6987) have shown that the three-membered ring has considerable hyperconjugative participation in the phenonium ion 6π aromatic system.
33. 2.
34. 2.
35. β bond lengths were considered for A3.
36. BDSHTRT (see ref 4c) was obtained as an average of the Gordy bond orders minus 1, and multipled by 100.
37. For 6, the LANL2DZ pseudopotential was used for tin and the D95 basis for the other atoms instead of 6-311+G** basis, d polarization functions (0.8 at carbon and 0.183 at tin) were added.
38. Le Serre, S.; Guillemin, J.-C.; Kárpáti, T.; Soós, L.; Nyulászi, L.; Veszprémi, T. J. Org. Chem. 1998, 63, 59.
39. Wiberg and Marquez (Wiberg, K. B.; Marquez, M. J. Am. Chem. Soc. 1998, 120, 2932) have discussed recently the effect of F substitution in small rings, noting the preference of F substitution on C atoms with enhanced p character.
40. The nucleus-independent chemical shift (NICS) is defined as a negative of the NMR shielding computed, e.g., in the ring center; see refs 4d and 9.
41. The NICS(π) values describe the π-contributions to the total NICS values (Schleyer, P. v. R.; Jiao, H.; Hommes, N. J. R. v. E.; Malkin, V. G.; Malkina, O. L. J. Am. Chem. Soc. 1997, 119, 12669).
42. Schaftenaar, G. MOLDEN 2.5; Caos/CAMM Center: Nijmengen, The Netherlands, 1994.
43. Jorgensen, W. L.; Salem, L. The Organic Chemist's Book of Orbitals. Academic Press: New York 1973
44. 2 groups forms a bridging bond above the C-C bond of the ring. These systems will be discussed elsewhere.
45. Blühmel, J.; Köhler, F. H. J. Organomet. Chem. 1988, 340, 303.