The effect of the p-nitro group on the chemistry of phenylnitrene. A study via intramolecular trapping

(Note: The full text of this document is currently only available in the PDF Version )

Angelo Albini, Gianfranco Bettinetti and *Giovanna Minoli


Abstract

The photodecomposition of a pyrazolyl substituted p-nitrophenyl azide has been studied as an intramolecular model for the reactivity of the parent azide, largely used for photochemical labelling. The singlet nitrene is trapped by intramolecular cyclization onto the pyrazole nitrogen as well as by the low yield addition of intermolecular nucleophiles (EtOH, Et2NH). Ring expansion to a didehydroazepine is absent. The triplet nitrene abstracts hydrogen (intermolecularly) only slightly more efficiently than the non-nitrated derivative, while it is rather efficiently reduced via electron transfer in the presence of amines. Hydrogen abstraction is efficient for the excited triplet nitrenes, as revealed by an intramolecular reaction.


References

  1. J. R. Knowles, Acc. Chem. Res., 1972, 5, 152 .
  2. H. Bailey, Photogenerated reagents in Biochemistry and Molecular Biology, Elsevier, New York, 1983 Search PubMed .
  3. M. S. Platz, E. Leyva and K. Heider, Org. Photochem., 1991, 11, 367 Search PubMed .
  4. G. B. Schuster and M. S. Platz, Adv. Photochem., 1992, 17, 69 Search PubMed .
  5. C. R. Kemnitz, W. L. Karney and W. T. Borden, J. Am. Chem. Soc., 1998, 120, 3499 CrossRef CAS .
  6. M. S. Platz, Acc. Chem. Res., 1995, 28, 487 CrossRef CAS .
  7. B. Iddon, O. Meth-Cohn, E. F. V. Scriven, H. Suschitzky and P. T. Gallagher, Angew. Chem., Int. Ed. Engl., 1979, 18, 900 CrossRef .
  8. E. Wasserman, Prog. Phys. Org. Chem., 1971, 8, 319 Search PubMed .
  9. S. P. Efimov, V. A. Smirnov and A. V. Pochinok, Khim. Vysok. Energ., 1983, 17, 445 Search PubMed .
  10. V. A. Smirnov and S. B. Brichkin, Chem. Phys. Lett., 1982, 87, 548 CrossRef CAS .
  11. R. A. Odum and A. M. Aaronson, J. Am. Chem. Soc., 1969, 91, 5680 CrossRef CAS .
  12. T. Y. Liang and G. B. Schuster, J. Am. Chem. Soc., 1987, 109, 7803 CrossRef CAS .
  13. M. J. Torres, J. Zayas and M. S. Platz, Tetrahedron Lett., 1986, 27, 791 CrossRef CAS .
  14. L. Dähne, J. Bendig and R. Stöβer, J. Prakt. Chem., 1992, 334, 707 .
  15. T. Harder, R. Stöβer, P. Wessig and J. Bendig, J. Photochem. Photobiol., 1997, 103, 105 Search PubMed .
  16. S. E. Carrol, B. Nay, E. F. V. Scriven, H. Suschitzky and D. R. Thomas, Tetrahedron Lett., 1977, 18, 3175 CrossRef .
  17. A. Albini, G. Bettinetti and G. Minoli, Chem. Lett., 1981, 301 .
  18. (a) A. Albini, G. Bettinetti and G. Minoli, J. Am. Chem. Soc., 1997, 119, 7308 CrossRef CAS ; (b) A. Albini, G. Bettinetti and G. Minoli, J. Am. Chem. Soc., 1999, 121, 3104 CrossRef CAS ; (c) A. Albini, G. Bettinetti and G. Minoli, Heterocycles., 1995, 40, 597 CAS .
  19. H. Tomioka, N. Ichikawa and K. Kamatsu, J. Am. Chem. Soc., 1993, 115, 8621 CrossRef CAS .
  20. R. A. Abramovitch, S. R. Challand and E. F. V. Scriven, J. Org. Chem., 1972, 37, 2705 CrossRef CAS .
  21. E. Leyva and R. Sagredo, Tetrahedron, 1998, 54, 7367 CrossRef CAS .
  22. N. P. Gritsan, Z. Zhu, C. M. Hadad and M. S. Platz, J. Am. Chem. Soc., 1999, 121, 1202 CrossRef CAS .
  23. J. Michl, J. Am. Chem. Soc., 1996, 118, 3568 CrossRef CAS .
  24. F. Kita, W. M. Nau, W. Adam and J. Wirz, J. Am. Chem. Soc., 1995, 117, 8670 CrossRef CAS .
  25. E. Leyva, M. S. Platz, G. Persy and J. Wirz, J. Am. Chem. Soc., 1986, 108, 3783 CrossRef CAS .
  26. S. J. Kim, T. P. Hamilton and H. F. Schaefer, J. Am. Chem. Soc., 1992, 114, 5349 CrossRef CAS .
Click here to see how this site uses Cookies. View our privacy policy here.