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Volumn 73, Issue 6, 2008, Pages 2198-2205

Arylbiphenylene atropisomers: Structure, conformation, stereodynamics, and absolute configuration

Author keywords

[No Author keywords available]

Indexed keywords

CHEMICAL BONDS; COMPUTER SIMULATION; ENERGY BARRIERS; LOW TEMPERATURE EFFECTS; X RAY DIFFRACTION;

EID: 41849133225     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo702502n     Document Type: Article
Times cited : (22)

References (129)
  • 1
    • 41849125607 scopus 로고    scopus 로고
    • In partial fulfilment of the requirements for the Ph.D. degree in Chemical Sciences, University of Bologna
    • In partial fulfilment of the requirements for the Ph.D. degree in Chemical Sciences, University of Bologna.
  • 38
    • 1642378139 scopus 로고    scopus 로고
    • Tumambac, G. E.; Wolf, C. J. Org. Chem. 2004, 69, 2048.2055.
    • (g) Tumambac, G. E.; Wolf, C. J. Org. Chem. 2004, 69, 2048.2055.
  • 48
    • 41849097363 scopus 로고    scopus 로고
    • Gaussian 03, Revision D.01: Frisch, M. J, Trucks, G. W, Schlegel, H. B, Scuseria, G. E, Robb, M. A, Cheeseman, J. R, Montgomery, J. A, Jr, Vreven, T, Kudin, K. N, Burant, J. C, Millam, J. M, Iyengar, S. S, Tomasi, J, Barone, V, Mennucci, B, Cossi, M, Scalmani, G, Rega, N, Petersson, G. A, Nakatsuji, H, Hada, M, Ehara, M, Toyota, K, Fukuda, R, Hasegawa, J, Ishida, M, Nakajima, T, Honda, Y, Kitao, O, Nakai, H, Klene, M, Li, X, Knox, J. E, Hratchian, H. P, Cross, J. B, Bakken, V, Adamo, C, Jaramillo, J, Gomperts, R, Stratmann, R. E, Yazyev, O, Austin, A. J, Cammi, R, Pomelli, C, Ochterski, J. W, Ayala, P. Y, Morokuma, K, Voth, G. A, Salvador, P, Dannenberg, J. J, Zakrzewski, V. G, Dapprich, S, Daniels, A. D, Strain, M. C, Farkas, O, Malick, D. K, Rabuck, A. D, Raghavachari, K, Foresman, J. B, Ortiz, J. V, Cui, Q, Baboul, A. G, Clifford, S, Cioslowski, J, Stefanov, B. B, Liu, G, Liashenko, A, Piskorz, P, Komaromi, I, Mar
    • Gaussian 03, Revision D.01: Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Montgomery, J. A., Jr.; Vreven, T.; Kudin, K. N.; Burant, J. C.; Millam, J. M.; Iyengar, S. S.; Tomasi, J.; Barone, V.; Mennucci, B.; Cossi, M.; Scalmani, G.; Rega, N.; Petersson, G. A.; Nakatsuji, H.; Hada, M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.; Ishida, M.; Nakajima, T.; Honda, Y.; Kitao, O.; Nakai, H.; Klene, M.; Li, X.; Knox, J. E.; Hratchian, H. P.; Cross, J. B.; Bakken, V.; Adamo, C.; Jaramillo, J.; Gomperts, R.; Stratmann, R. E.; Yazyev, O.; Austin, A. J.; Cammi, R.; Pomelli, C.; Ochterski, J. W.; Ayala, P. Y.; Morokuma, K.; Voth, G. A.; Salvador, P.; Dannenberg, J. J.; Zakrzewski, V. G.; Dapprich, S.; Daniels, A. D.; Strain, M. C.; Farkas, O.; Malick, D. K.; Rabuck, A. D.; Raghavachari, K.; Foresman, J. B.; Ortiz, J. V.; Cui, Q.; Baboul, A. G.; Clifford, S.; Cioslowski, J.; Stefanov, B. B.; Liu, G.; Liashenko, A.; Piskorz, P.; Komaromi, I.; Martin, R. L.; Fox, D. J.; Keith, T.; Al-Laham, M. A.; Peng, C. Y.; Nanayakkara, A.; Challacombe, M.; Gill, P. M. W.; Johnson, B.; Chen, W.; Wong, M. W.; Gonzalez, C.; Pople, J. A. Gaussian, Inc., Wallingford CT, 2004.
  • 49
    • 33847137786 scopus 로고    scopus 로고
    • In a theoretical paper describing compounds analogous to 1 only one of the two possible anti conformers was, inexplicably, considered see: Bigdeli, M. A, Moradi, S, Nemati, F. J. Mol. Structure Theochem. 2007, 807, 125-135
    • In a theoretical paper describing compounds analogous to 1 only one of the two possible anti conformers was, inexplicably, considered (see: Bigdeli, M. A.; Moradi, S.; Nemati, F. J. Mol. Structure Theochem. 2007, 807, 125-135).
  • 50
    • 0011995547 scopus 로고    scopus 로고
    • S⊄. See, for instance: Dondoni, A.; Lunazzi, L.; Giorgianni, P.; Macciantelli, D. J. Org. Chem. 1975, 20, 2979.
    • S⊄. See, for instance: Dondoni, A.; Lunazzi, L.; Giorgianni, P.; Macciantelli, D. J. Org. Chem. 1975, 20, 2979.
  • 68
    • 0015131932 scopus 로고    scopus 로고
    • Dissimilarities between the conformations in solution with respect to the structures found in the solids have been reported; see: Johansen, J. T, Vallee, B. L. Proc. Nat. Acad. Sci. U.S.A. 1971, 68, 2532-2535
    • Dissimilarities between the conformations in solution with respect to the structures found in the solids have been reported; see: Johansen, J. T.; Vallee, B. L. Proc. Nat. Acad. Sci. U.S.A. 1971, 68, 2532-2535.
  • 70
    • 0030794823 scopus 로고    scopus 로고
    • Burke, L. P.; DeBellis, A. D.; Fuhrer, H.; Meier, H.; Pastor, S. D.; Rihs, G.; Rist, G.; Rodebaugh, R. K.; P. Shum, S. P. J. Am. Chem. Soc. 1997, 119, 8313-8323.
    • Burke, L. P.; DeBellis, A. D.; Fuhrer, H.; Meier, H.; Pastor, S. D.; Rihs, G.; Rist, G.; Rodebaugh, R. K.; P. Shum, S. P. J. Am. Chem. Soc. 1997, 119, 8313-8323.
  • 74
    • 17444369440 scopus 로고    scopus 로고
    • A situation where it has been unambiguously demonstrated that the structure observed by X-ray diffraction in the crystal is that of the minor conformer present in solution has been reported in: Lunazzi, L, Mazzanti, A, Minzoni, M, Anderson, J. E. Org. Lett. 2005, 7, 1291-1294
    • A situation where it has been unambiguously demonstrated that the structure observed by X-ray diffraction in the crystal is that of the minor conformer present in solution has been reported in: Lunazzi, L.; Mazzanti, A.; Minzoni, M.; Anderson, J. E. Org. Lett. 2005, 7, 1291-1294.
  • 75
    • 41849090046 scopus 로고    scopus 로고
    • It has to be taken into account that the syn conformer exists as four degenerate forms (two identical pairs of enantiomers, whereas the anti-in exists solely as two degenerate forms, corresponding to a pair of enantiomers (the presence of the anti-out can be, in practice, neglected, since its higher relative energy of 0.9 kcal mol-1 would correspond to a proportion lower than 8% at -92°C, Owing to the greater probability, the actual population of the syn conformer might be higher than expected solely on the basis of its computed energy. In fact, both of the anti forms belong to the C2 point group and are therefore disfavored by RT In 2 i.e, 0.24 kcal mol-1 at -92° C, see: Eliel, E. L, Wilen, S. H. Stereochemistry of Organic Compounds; Wiley: New York, 1994; pp 97 and 601, Accordingly, when corrected for this factor the energy difference becomes 0.06 kcal mol-1, a value that corresponds to an anti/syn ratio o
    • -1, a value that corresponds to an anti/syn ratio of 54/46. When the proportions are so close to 50/50, the approximations involved in the computed energy do not allow one to obtain a reliable assignment for the situation in solution because, in these conditions, even a small solvent effect might cause a reversal of the assignment.
  • 79
    • 84987321344 scopus 로고    scopus 로고
    • When the rotation about the aryl-biphenylene bond is frozen, the methylene hydrogens are diastereotopic because the conformers adopt a non planar conformation. For the same reason are diastereotopic at low temperature the methyl groups of the isopropyl moieties of compound 3. See: Mislow, K.; Raban, M. Top. Stereochem. 1967, 1, 1.
    • When the rotation about the aryl-biphenylene bond is frozen, the methylene hydrogens are diastereotopic because the conformers adopt a non planar conformation. For the same reason are diastereotopic at low temperature the methyl groups of the isopropyl moieties of compound 3. See: Mislow, K.; Raban, M. Top. Stereochem. 1967, 1, 1.
  • 83
    • 0004028219 scopus 로고
    • Newman, M. S, Ed, John Wiley and Sons, Inc, New York, Chapter 12
    • (a) Westheimer, F. H. In Steric Effects in Organic Chemistry; Newman, M. S., Ed.; John Wiley and Sons, Inc.: New York, 1956; Chapter 12.
    • (1956) Steric Effects in Organic Chemistry
    • Westheimer, F.H.1
  • 90
    • 41849102691 scopus 로고    scopus 로고
    • Irradiation (Figure S-2 of the Supporting Information) of the major signal of the methyls in position 3,3′ of the xylyl rings (1.67 ppm) of 5, yields enhancement for the major signal of the corresponding hydrogens in position 4,4′ (6.90 ppm) of the same xylyl rings and for the major signal of the hydrogens in positions 5′,5 (6.96 ppm) of the other ring, as expected for an anti conformer, where the latter distance is short enough to produce NOE effects. On the contrary irradiation of the minor signal (1.86 ppm) of the methyls in position 3,3′ of the xylyl rings, enhances solely the minor signal of the corresponding hydrogens in position 4,4′ of the same ring (6.74 ppm, Likewise irradiation of the major signals of the methyl in positions 2,2′ of the xylyl rings (1.37 ppm) enhances the corresponding signals of the hydrogens in positions 2,7 of the biphenylene moiety (6.59 ppm) and also that of the hydrogens in positions 6′,6 of the other x
    • Irradiation (Figure S-2 of the Supporting Information) of the major signal of the methyls in position 3,3′ of the xylyl rings (1.67 ppm) of 5, yields enhancement for the major signal of the corresponding hydrogens in position 4,4′ (6.90 ppm) of the same xylyl rings and for the major signal of the hydrogens in positions 5′,5 (6.96 ppm) of the other ring, as expected for an anti conformer, where the latter distance is short enough to produce NOE effects. On the contrary irradiation of the minor signal (1.86 ppm) of the methyls in position 3,3′ of the xylyl rings, enhances solely the minor signal of the corresponding hydrogens in position 4,4′ of the same ring (6.74 ppm). Likewise irradiation of the major signals of the methyl in positions 2,2′ of the xylyl rings (1.37 ppm) enhances the corresponding signals of the hydrogens in positions 2,7 of the biphenylene moiety (6.59 ppm) and also that of the hydrogens in positions 6′,6 of the other xylyl ring (6.96 ppm). On the contrary, irradiation of the minor signal of the methyl groups (1.76 ppm) enhances solely the corresponding H2,7 minor signal of biphenylene (6.60 ppm), as expected for a syn conformer where the distance between the hydrogens of the methyl in position 2 of one ring and the hydrogen in position 6′ of the other ring is too large to yield a NOE effect.
  • 91
    • 41849109437 scopus 로고    scopus 로고
    • The conformational assignment in compounds 3 and 4 was obtained by means of the mentioned low temperature NOE experiments.
    • The conformational assignment in compounds 3 and 4 was obtained by means of the mentioned low temperature NOE experiments.
  • 92
    • 41849147101 scopus 로고    scopus 로고
    • 2) employed for measuring the barriers of compounds 1-3 and 5.
    • 2) employed for measuring the barriers of compounds 1-3 and 5.
  • 93
    • 41849084443 scopus 로고    scopus 로고
    • The lower proportion of the conformer anti observed in compound 4 with respect to 3 might be also interpreted as the consequence of a statistic effect, due to the possibility of having both the anti-in and anti-out situations in the case of 3, whereas solely a single anti form occurs in 4.
    • The lower proportion of the conformer anti observed in compound 4 with respect to 3 might be also interpreted as the consequence of a statistic effect, due to the possibility of having both the anti-in and anti-out situations in the case of 3, whereas solely a single anti form occurs in 4.
  • 94
    • 4644357388 scopus 로고    scopus 로고
    • Lunazzi, L.; Mazzanti, A. J. Am. Chem. Soc. 2004, 126, 12155-12157. See also ref 10c.
    • Lunazzi, L.; Mazzanti, A. J. Am. Chem. Soc. 2004, 126, 12155-12157. See also ref 10c.
  • 95
    • 41849085143 scopus 로고    scopus 로고
    • 6 lies in a position that does not interfere with the signals of 6b).
    • 6 lies in a position that does not interfere with the signals of 6b).
  • 96
    • 41849130591 scopus 로고    scopus 로고
    • The isomer anti (6b) displays a methyl signal at a substantially higher field than the methyl signal of the isomer syn (6a) owing to the effect of the aromatic ring currents, since in the anti situation the methyl groups lie above the plane of the naphthalene rings, see: Jackman, L. M.; Sternhell, S. Applications of NMR Spectroscopy in Organic Chemistry, 2nd ed.; Pergamon Press: Oxford, 1969; p 95.
    • The isomer anti (6b) displays a methyl signal at a substantially higher field than the methyl signal of the isomer syn (6a) owing to the effect of the aromatic ring currents, since in the anti situation the methyl groups lie above the plane of the naphthalene rings, see: Jackman, L. M.; Sternhell, S. Applications of NMR Spectroscopy in Organic Chemistry, 2nd ed.; Pergamon Press: Oxford, 1969; p 95.
  • 101
    • 0037431283 scopus 로고    scopus 로고
    • For the assignments made by TDDFT-CD calculations see: a
    • For the assignments made by TDDFT-CD calculations see: (a) Diedrich, C.; Grimme, S. J. Phys. Chem. A 2003, 107, 2524.
    • (2003) J. Phys. Chem. A , vol.107 , pp. 2524
    • Diedrich, C.1    Grimme, S.2
  • 114
  • 121
    • 0029739928 scopus 로고    scopus 로고
    • For the preparation of the intermediate 2,2′,6,6′- tetrabromobiphenyl, see: Rajca, A.; Safronov, A.; Rajca, S.; Ross, C. R., II; Stezowski, J. J. J. Am. Chem. Soc. 1996, 118, 7272-7279.
    • For the preparation of the intermediate 2,2′,6,6′- tetrabromobiphenyl, see: Rajca, A.; Safronov, A.; Rajca, S.; Ross, C. R., II; Stezowski, J. J. J. Am. Chem. Soc. 1996, 118, 7272-7279.
  • 123
    • 32844469362 scopus 로고    scopus 로고
    • Pathak, R.; Nhlapo, J. M.; Govender, S.; Michael, J. P.; Van, Otterlo, W. A. L.; De Koning, C. B. Tetrahedron 2006, 62, 2820-2830.
    • Pathak, R.; Nhlapo, J. M.; Govender, S.; Michael, J. P.; Van, Otterlo, W. A. L.; De Koning, C. B. Tetrahedron 2006, 62, 2820-2830.
  • 128


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