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DOI: 10.1039/A607548G (Paper) Reference Section for: J. Chem. Soc., Perkin Trans. 2, 1997, 1585-1596

Base-catalysed ring openings of 1,2-diphenylcycloalkanols having five-, six-, seven- and eight-membered rings

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Sayid M. Moosavi, Roy S. Beddoes and C. Ian F. Watt

Abstract

trans-Isomers of 1,2-diphenylcyclopentanol, 5, 1,2-diphenylcyclohexanol, 6, 1,2-diphenylcycloheptanol, 7, and 1,2-diphenylcyclooctanol, 8, have been prepared as have their acyclic analogues, threo- and erythro-3,4-diphenylhexan-3-ol, 9. All structural assignments are confirmed by X-ray crystal structure determinations and experimentally determined structures are compared with the results of empirical force field calculations which also yield strain energies for each of the compounds. With alkali metal dimsyl–dimethyl sulfoxide or 1,3-diaminopropane with its potassium salt as base, the cycloalkanols are isomerised to enolates of corresponding 1,n-diphenylalkan-1-ones, and the acyclic alkanols cleaved to propylbenzene and the enolate of propiophenone. The products are consistent with a polar mechanism involving collapse of alkoxide to expel a benzylic carbanion, followed by one or more proton transfers to yield the observed products. Rates increase in the order, 6 < 5 [double less-than, compressed] 7 < 9 < 8, with a spread in reactivities of ca. 106. Logarithms of relative rates correlate poorly with estimates of strain release in the reactions. Correlations are improved by incorporation of estimates of entropy changes associated with ring opening or cleavage, but remain poor. The fate of isotopic labels in the reactions of 2,n,n-trideuterio-1,2-diphenylcycloalkanols. [2H3]-5, [2H3]-7 and [2H3]-8, shows that protonation of the benzylic carbanion is by solvent DMSO for the cyclooctanol, [2H3]-8, and that competing intramolecular proton transfer occurs in the cycloheptanol, [2H3]-7, and cyclopentanol, [2H3]-5. Kinetic isotope effects associated with the labelling patterns are consistent with a change in rate-limiting step from the initial carbon–carbon bond cleavage in the case of 8, to rate-limiting proton transfer in the case of 5.

References

  1. S. Partington and C. I. F. Watt, J. Chem. Soc., Perkin Trans. 2, 1988, 981 Search PubMed.
  2. S. Ibrahim, K. J. Msayib, C. I. F. Watt and J. M. Wilson, J. Chem. Soc., Perkin Trans. 2, 1992, 1703 RSC.
  3. C. J. M. Stirling, Chem. Rev., 1978, 78, 517 CrossRef CAS.
  4. Most recently F. C. Lighthouse and T. C. Bruice, J. Am. Chem. Soc., 1996, 118, 2595 Search PubMed.
  5. A. Thiblin and W. P. Jencks, J. Am. Chem. Soc., 1979, 101, 4963 CrossRef CAS.
  6. P. Forward, W. N. Hunter, G. A. Leonard, J. Palou, D. Walmsley and C. I. F. Watt, J. Chem. Soc., Perkin Trans. 2, 1993, 931 RSC.
  7. T. D. Hoffman and D. J. Cram, J. Am. Chem. Soc., 1969, 99, 1000 and 1009 CrossRef.
  8. For relevant discussion of the limitations of the Karplus-Conroy relationship see L. M. Jackman and S. Sternhall, Applications of NMR Spectroscopy in Organic Chemistry, 2nd edn., Pergamon, New York, 1969 Search PubMed.
  9. J. D. Dunitz, X-ray Analysis and the Structure of Organic Molecules, Cornell University Press, Ithaca, 1979 Search PubMedfor most recent review A. J. Kirby, Adv. Phys. Org. Chem., 1994, 29, 87 Search PubMed.
  10. N. L. Allinger, Z.-Q. S. Zhu and K. Chen, J. Am. Chem. Soc., 1992, 114, 6120 CrossRef CAS and references therein.
  11. F. Mohamadi, N. G. J. Richards, W. C. Guida, R. Liskamp, C. Caulfield, G. Chang, T. Hendrojson and W. C. Still, J. Comput. Chem., 1990, 11, 440 CrossRef CAS.
  12. For discussion of the concept of strain background references see J. F. Leibmann and A. Greenberg, Strained Organic Molecules, Academic Press, New York, 1978, ch. 1 Search PubMed.
  13. H. Zook, J. March and D. Smith, J. Am. Chem. Soc., 1959, 81, 1617 CrossRef CAS.
  14. E. M. Arnett, L. E. Small, R. T. McIver and J. S. Miller, J. Org. Chem., 1978, 43, 815 CrossRef CAS.
  15. J. Lomas and J. Dubois, J. Org. Chem., 1984, 49, 2067 CrossRef CAS.
  16. For collected pKa data see F. G. Bordwell, Acc. Chem. Res., 1988, 21, 456 Search PubMed; R. W. Taft and F. G. Bordwell, Acc. Chem. Res., 1988, 21, 463 CrossRef CAS.
  17. J. H. Exner and E. C. Steiner, J. Am. Chem. Soc., 1974, 96, 1782 CrossRef CAS.
  18. E. M. Arnett, K. G. Venkatasubramian, R. T. McIver Jr., F. G. Bordwell and R. D. Press, J. Org. Chem., 1983, 48, 1569 CrossRef CAS.
  19. M. I. Page, J. Mol. Catalysis, 1988, 47, 241 Search PubMed; M. I. Page and W. P. Jencks, Procl. Natl. Acad. Sci., USA, 1971, 68, 1678 Search PubMed.
  20. M. I. Page, Angew. Chem., Int. Ed., Engl., 1976, 16, 449 CrossRef.
  21. I. A. Shapiro and N. G. Zharova, Zh. Org. Khim., 1989, 25, 1813(see Chem. Abstr., 1989, 112, 138 516; 1989, 113, 114576z Search PubMed.
  22. J. E. Homan, R. J. Muller and A. Schriesheim, J. Am. Chem. Soc, 1963, 85, 3000 and 3002 CrossRef; D. W. Boerth and A. Streitwieser Jr., J. Am. Chem. Soc., 1981, 103, 6443 CrossRef CAS.
  23. L. Melander and W. H. Saunders Jr., Reaction Rates of Isotopic Molecules, Wiley, New York, 1980, pp. 95–102 Search PubMed.
  24. A. Streitweiser Jr., R. H. Jagow, R. C. Fahey and S. Suzuki, J. Am. Chem. Soc., 1958, 80, 6764.
  25. J. J. Gajewski and K. R. Gee, J. Am. Chem. Soc., 1991, 113, 967 CrossRef CAS.
  26. N. J. Harris and J. J. Gajewski, J. Am. Chem. Soc., 1994, 116, 6121 CrossRef CAS.
  27. F. H. Westheimer, Chem. Rev., 1961, 61, 265 CrossRef CAS.
  28. For collected data on kie dependences on ΔpKa see Proton Transfer Reactions, ed. E. Caldin and V. Gold, Chapman and Hall, London, 1975, pp. 222–227 Search PubMed.
  29. K. Biemann, Mass Spectrometry: Organic Chemical Applications, McGraw-Hill, New York, 1962 Search PubMed.
  30. P. Tamboulian, J. Org. Chem., 1961, 26, 2652 CrossRef.
  31. A. C. Cope and D. S. Smith, J. Am. Chem. Soc., 1952, 74, 5136 CrossRef CAS.
  32. Z. Zafiriadissss, C.R. Acad. Sci., 1949, 228, 852 Search PubMed.
  33. A. J. Mancusco, S. L. Huang and D. Swern, J. Org. Chem, 1978, 43, 2480 CrossRef CAS.
  34. F. Ramirez and S. Dershowitz, J. Org. Chem., 1957, 22, 41 CrossRef CAS.
  35. N. Walker and D. Stuart, Acta Crystallogr., Sect. A., 1983, 39, 158 CrossRef.
  36. G. M. Sheldrick and SHELXS-86 in Crystallographic Computing 3, ed. G. M. Sheldrick, C. Krueger and R. Goddard, pp. 175–9. Oxford University Press, Oxford, 1985 Search PubMed.
  37. D. T. Cromer and J. T. Waber, in International Tables for X-ray Crystallography, The Kynoch Press, Birmingham, 1974, vol. 4, Table 2.2 Search PubMed.
  38. J. A. Ibers and W. C. Hamilton, Acta Crystallogr., 1964, 17, 781 CrossRef.
  39. TEXSAN, Structure analysis package, Molecular Structure Corporation, Houston, Texas, USA, 1985.
  40. C. K. Johnson, ORTEP2 Report ORNL-5138, 1976, Oak Ridge National Laboratory, Oak Ridge, Teenessee, USA.
  41. S. Motherwell and W. Clegg, PLUTO Programme for plotting molecular structures and crystals, Cambridge University, England, 1978 Search PubMed.
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