Bulletin of the Korean Chemical Society

Korean Chemical Society (대한화학회)
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Transmission Substituent Effects through Five-Membered Heteroaromatic Rigns, Ⅱ. Deprotonation Equilibra of Phenol Analogues

  • Published : 20000900
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Abstract

Transmission of substituent effects through 5-membered heteroaromaticrings isinvestigated theoretically at the RHF/6-31+G* and B3LYP/6-31+G* levelsusing the deprotonation equilibria of phenol analogues with heteroatoms Y = NH, O, PHand S. The incr ease in the resonance delocalization of the $\pilone-pair$ on the phe-nolic oxygen atom, $n\pi(O)$, accompanied with the deprotonation depends on the heteroatom Y,in the order NH < O < PH < S. This represents the $\pielectron$ accepting ability, or conversely reverse order of the $\pielectron$ donating ability of the $\pilone-pair$ on Y, $n\pi(Y).$ The transmission efficiency of substituenteffects is, however,in the reverse order NH > O > S, which represents the order of delocalizability of $n\pi(Y).$ A better correlation is obtained with ${\sigma}p$ - than with ${\sigma}p$ for the Hammett type plots with the positive slope, $\rho-$ > 0, of the magnitude in the same order as that for the delocalizability of $n\pi(Y).$ Thedeprotonation energy, ΔG = [G(PA) + G(H+)] -G(P), decreases with the increasein the extence delocalization in the order NH > O > PH > S.

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References

  1. Bull. Korean Chem. Soc. Lee, I.;Rhee, S. K.;Kim, C. K.;Chung, D. S.;Kim, C. K.
  2. J. Correlation Analysis in Chemistry The reaction system of eq (1) is considered as a formal analogue of para-substituted benzene derivatives; Chapman, N. B.;Shorter,
  3. Bull. Chem. Soc. Jpn. v.39 Yukawa, Y.;Tsuno, Y.;Sawada, M.
  4. J. Am. Chem. Soc. v.96 London, G. M.;Berke, C.
  5. Phys. Rev. v.136 Hohenberg, P.;Kohn, W.
  6. J. Phys. Rev. v.140 Kohn, W.;Sham, L.
  7. J. Chem. Phys. v.98 Becke, A. D.
  8. Phys. Rev. v.B37 Lee, C.;Yang, W.;Parr, R. G.
  9. Chem. Phys. Lett. v.157 Miehlich, B.;Savin, A.;Stoll, H.;Preuss, H.
  10. Abinitio Molecular Orbital Theory Hehre, W. J.;Radom, L.;Schleyer, P. v. R.;Pople, J. A.
  11. Int. J. Quantum Chem. v.S13 Pople, J. A.;Krishnan, R.;Schlegel, H. B.;Binkley, J. S.
  12. ibid. v.S15 Pople, J. A.;Schlegel, H. B.;Krishnan, R.;DeFree, D. J.;Binkley, J. S.;Frisch, M. J.;Whiteside, R. A.;Haut, R. F.;Hehre, W.
  13. J. Phys. Chem. v.100 Scott, A. P.;Radom, L.
  14. Exploring Chemistry with Electronic Structure Methods ($2^{nd} ed.$) Foresman, J. B.;Frisch, A. E.
  15. J. Chem. Phys. v.65 Miertus, S.;Tomasi, J.
  16. J. Chem. Phys. v.55 Miertus, S.;Scrocco, E.;Tomasi, J.
  17. J. Phys. Chem. v.100 Chamber, C. C.;Hawkins, G. D.;Cramer, C. J.;Truhlar, D. G.
  18. J. Am. Chem. Soc. v.101 Brunck, T. K.;Weinhold, F.
  19. Chem. Rev. v.88 Reed, A. E.;Curtiss, L. A.;Weinhold, F.
  20. J. Comput. Chem. v.19 no.593 Glendening, E. D.;Weinhold, F.
  21. J. Comput. Chem. v.19 Glendening, E. D.;Badenhoop, J. K.;Weinhold, F.
  22. J. Am. Chem. Soc. v.121 Stowasser, R.;Hoffmann, R.
  23. Gaussian 98, Revision A.6. Frisch, M. J.;Trucks, G. W.;Schlegel, H. B.;Scuseria, G. E.;Robb, M. A.;Cheeseman, J. R.;Zakrzewski, V. G.;Montgomery, Jr., J. A.;Stratmann, R. E.;Burant, J. C.;Dapprich, S.;Millam, J. M.;Daniels, A. D.;Kudin, K. N.;Strain, M. C.;Farkas, O.;Tomasi, J.;Barone, V.;Cossi, M.;Cammi, R.;Mennucci, B.;Pomelli, C.;Adamo, C.;Clifford, S.;Ochterski, J.;Petersson, G. A.;Ayala, P. Y.;Cui, Q.;Morokuma, K.;Malick, D. K.;Rabuck, A. D.;Raghavachari, K.;Foresman, J. B.;Cioslowski, J.;Ortiz, J. V.;Stefanov, B. B.;Liu, G.;Liashenko, A.;Piskorz, P.;Komaromi, I.;Gomperts, R.;Martin, R. L.;Fox, D. J.;Keith, T.;Al-Laham, M. A.;Peng, C. Y.;Nanayakkara,A.;Gonzalez, C.;Challacombe, M.;Gill, P. M. W.;Johnson, B.;Chen, W.;Wong, M. W.;Andres, J. L.;Gonzalez, C.;Head Gordon, M.;Replogle, E. S.;Pople, J. A.
  24. J. Am. Chem. Soc. v.90 Swain, C. G.;Lupton, E. C.
  25. J. Am. Chem. Soc. v.105 Swain, C. G.;Unger, S. H.;Rosenquist, N. R.;Swain, M. S.
  26. Mechanism in Organic Chemistry Alder, R. W.;Baker, R.;Brown, J. M.
  27. Physical Organic Chemistry Hammett, L. P.
  28. N. Physical Organic Chemistry ($2^{nd}$ Ed.) The values of substituent constants,σ and σ-,are taken from: Isaacs,