Skip to main content
SpringerLink
Log in

Radical reactions of N-heterocyclic compounds, XV. Radial intermediates and end products of the oxidation of 3-anilino-1,5-diphenylpyrazoles with Pb(OAc)4

Radikalreaktionen von N-Heterocyclen, 15. Mitt. Intermediäre Radikale und Endprodukte der Oxidation von 3-Anilino-1,5-diphenylpyrazolen mit Pb(OAc)4

  • Organische Cheme Und Biochemie
  • Published:
Monatshefte für Chemie / Chemical Monthly Aims and scope Submit manuscript

Summary

Substituted 3-anilino-1,5-diphenylpyrazoles1a–i were oxidized with Pb(OAc)4 in benzene or CH2Cl2 solution. The ESR measurements confirmed the formation of aminyl radicals3f–i frompara-CH3 substituted pyrazoles1f–i. The radical intermediates from unsubstituted pyrazoles1a–e were assigned to triarylaminium cation radicals These were generated by consecutive oxidation of the dimeric products4a–e whose structure was proven by NMR spectroscopy and15N labeling.

Zusammenfassung

Die substituierten 3-Anilino-1,5-diphenylpyrazole1a–i wurden mit Pb(OAc)4 in Benzol oder CH2Cl2 oxidiert. Die intermediären Aminylradikale3f–i wurden ESR-spektroskopisch bei der Oxidation der im Anilinrest methylsubstituierten Pyrazole1f–i nachgewiesen. Die ESR-spektroskopisch nach Oxidation der Pyrazole1a–e beobachteten Radikalintermediate interpretieren wir als Kationradikale6a–e. Diese werden durch Weiteroxidation der Dimeren4a–e gebildet, deren Struktur durch NMR-Untersuchungen und15N-Markierung bewiesen wurde.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Part XIV: Kluge R, Schulz M, Pôbišova M, Nüchter M (1994) Chem Ber127: 1729

    Google Scholar 

  2. Schulz M, Mögel L, Seifarth K (1984) Plaste Kautsch31: 92 [(1984) Chem Abstr101, 24438d]

    Google Scholar 

  3. Schulz M, Mögel L, Omelka L, Tkac A (1986) J Prakt Chem328: 222

    Google Scholar 

  4. Omelka L, Reinhardt M, Kluge R, Schulz M (1988) Collect Czech Chem Commun53: 243

    Google Scholar 

  5. Omelka L, Meske M, Cholvad V, Svetlik J, Schulz M (1992) Collect Czech Chem Commun57: 1065

    Google Scholar 

  6. Thomas J (1960) J Am Chem Soc82: 5955

    Google Scholar 

  7. Caproiu MT, Negoita N, Balaban AT (1983) Tetrahedron39: 3943

    Google Scholar 

  8. Forrester AE, Johansson EM, Thomson RH (1979) J Chem Soc Perkin Trans 1, 1112

    Google Scholar 

  9. Danen WC, Neugebauer FA (1975) Angew Chem87: 823

    Google Scholar 

  10. 13C NMR spectra of different phenyl-substituted pyrazoles including1a, 1c, 1d, 1f, and1h have been investigated earlier: Mögel L, Schulz M, Radeglia R, Osten HJ (1984) J Prakt Chem326: 54

    Google Scholar 

  11. Begtrup M, Bayer G, Cabildo P, Cativiela C, Claramunt RM, Elguero J, Gareira JI, Toiron C, Vesdo P (1993) Magn Reson Chem31: 107

    Google Scholar 

  12. Martin GJ, Martin ML, Gousnard J P (198115N NMR Spectroscopy. In: NMR Basic Principles and Progress 18. Springer, Berlin Heidelberg New York;

    Google Scholar 

  13. Schuster II, DyllicBrenzinger C, Roberts J (1979) J Org Chem44: 1765

    Google Scholar 

  14. Neugebauer FA, Fischer PH (1966) Z Naturforsch21b: 1036

    Google Scholar 

  15. Neugebauer FA, Bamberger S (1974) Chem Ber107: 2362

    Google Scholar 

  16. Neugebauer FA, Bamberger S, Groh WR (1975) Chem Ber108: 2406

    Google Scholar 

  17. Hünig S, Hübner K (1962) Chem Ber95: 937

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Institute of Organic Chemistry, Martin Luther University Halle-Wittenberg, D-06217, Merseburg, Germany

    R. Kluge, D. Ströhl, M. T. da Silva & M. Schulz

  2. Department of Physical Chemistry, Faculty of Chemical Technology, Slovak Technical University, SK-81237, Bratislava, Slovak Republic

    L. Omelka

Authors
  1. R. Kluge
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. D. Ströhl
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. L. Omelka
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. M. T. da Silva
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. M. Schulz
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kluge, R., Ströhl, D., Omelka, L. et al. Radical reactions of N-heterocyclic compounds, XV. Radial intermediates and end products of the oxidation of 3-anilino-1,5-diphenylpyrazoles with Pb(OAc)4 . Monatsh Chem 128, 261–270 (1997). https://doi.org/10.1007/BF00807892

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00807892

Keywords

Search

Navigation