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The Effect of Polarizability on Rate and Reaction Mechanism: Reactions of S-Aryl Substituted Thiobenzoates with $HO-$ and Aryloxide Ions

  • Ik-Hwan Um (Department of Chemistry, Ewha Womans University) ;
  • Sang-Eun Chun (Department of Chemistry, Ewha Womans University) ;
  • Dong-Sook Kwon (Department of Chemistry, Ewha Womans University)
  • 발행 : 1991.10.20

초록

Second-order rate constants have been determined spectrophotometrically for reactions of S-p-nitrophenyl substituted thiobenzoates with various phenoxide ions and S-aryl substituted thiobenzoates with $HO^-$ ion. Thiol esters have been found to be more reactive than the corresponding oxygen esters toward phenoxide ions. The high reactivity of thiol esters relative to oxygen esters becomes insignificant as the basicity of the nucleophile increases. Furthermore, the highly basic $HO^-$ ion is less reactive toward thiol esters than oxygen esters. The significant dependence of the reactivity of thiol esters on the basicity of nucleophiles has been attributed to the nature of the HSAB principle. The present kinetic study has also revealed that the reactivity of thiol esters compared to oxygen esters is not so pronounced as expected based on the enhanced nucleofugicity of thiol esters. However, the effects of substituents in the nucleophile and in the acyl moiety of the substrate on rate appear to be significant. These kinetic results have led to a conclusion that the present reactions proceed via a rate-determining formation of a tetrahedral intermediate followed by a fast breakdown of it. The magnitude of the ${\beta}$ values shows no tendency either to increase or to decrease with the intrinsic reactivity of the reagents. The constancy of ${\beta}$ values in the present system is suggestive that the RSP should have limited applicability.

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참고문헌

  1. The Chemistry of Carboxylic Acids And Esters J. Janssen;S. Patai(ed.)
  2. J. Am. Chem. Soc. v.82 A. W. Baker;G. H. Harris
  3. J. Org. Chem. v.26 K. A. Connors;M. L. Bender
  4. J. Chem. Soc. (B) A. J. Collings;P. F. Jackson;K. J. Morgan
  5. J. Org. Chem. v.38 J. P. Idoux;P. T. R. Hwong;C. K. Hancock
  6. J. Am. Chem. Soc. v.99 D. J. Hupe;D. Wu
  7. J. Am. Chem. Soc. v.99 D. J. Hupe;W. P. Jencks
  8. Spectrochimica Acta v.17 R. A. Nyquist;W. J. Potts
  9. J. Am. Chem. Soc. v.99 E. A. Noe
  10. J. Org. Chem. v.42 C. M. Hall;J. M. Wemple
  11. Phosphorus and Sulfur v.9 C. A. Kingsbury;G. Ebert
  12. Bull. Korean Chem. Soc. v.10 D. S. Kwon;K. E. Choi;I. H. Um
  13. Bull. Korean Chem. Soc. v.11 I. H. Um;K. E. Choi;D. S. Kwon
  14. J. AM. Chem. Soc. v.85 R. G. Pearson
  15. Bull. Korean Chem. Soc. v.12 I. H. Um;J. S. Jeon;D. S. Kwon
  16. J. Am. Chem. Soc. v.109 S. Ba-Saif;A. K. Luthra;A. Williams
  17. Acc. Chem. Res. v.22 A. Williams
  18. J. Am. Chem. Soc. v.111 S. Ba-Saif;A. K. Luthra;A. Williams
  19. J. Am. Chem. Soc. v.109 J. F. Blake;W. L. Jorgensen
  20. J. Am. Chem. Soc. v.111 E. Buncel;I. H. Um;S. Hoz
  21. J. Am. Chem. Soc. v.110 E. Buncel;S. S. Shaik;I. H. Um;S. Wolfe
  22. Bull. Korean. Chem. Soc. v.11 D. S. Kwon;G. J. Lee;I. H. Um
  23. Bull. Korean. Chem. Soc. v.12 D. S. Kwon;H. S. Park;I. H. Um
  24. Practical Organic Chemistry A. I. Vogel
  25. J. Am. Chem. Soc. v.100 J. P. Guthrie
  26. J. Am. Chem. Soc. v.99 J. T. Edward;S. C. Wong
  27. Handbook of Biochemistry. Selected data for Molecualr Biology W. P. Jencks;F. Regenstein;H. A. Sober(ed.)
  28. Advanced Organic Chemistry; Reactions, Mechanisms, and Structure(2nd ed.) J. March
  29. J. Am. Chem. Soc. v.94 F. M. Menger;J. H. Smith
  30. J. Chem. Ed. v.64 E. Buncel;H. Wilson
  31. Acc. Chem. Res. v.11 E. M. Arnett
  32. Tetrahedron v.36 E. D. Johson
  33. Adv. Phys. Org. Chem. v.14 A. Pross
  34. J. Org. Chem. v.45 F. G. Bordwell;D. L. Hughes
  35. J. Org. Chem. v.33 J. F. Kirsh;W. Clewell;A. Simon

피인용 문헌

  1. Reactions of Aryl 5-substituted-2-Thiophenecarboxylates Promoted by 4-Z-C6H4O/4-Z-C6H4OH in 20 mol % DMSO(aq). Effect of Nucleophile on A vol.36, pp.12, 1991, https://doi.org/10.1002/bkcs.10567