Central European Journal of Chemistry

, Volume 2, Issue 4, pp 672–685 | Cite as

Structural factors influencing the reaction rates of 4-aryloxy-7-nitrobenzofurazans with amino acids

  • Marioara Bem
  • Marilena Vasilescu
  • Miron T. Caproiu
  • Constantin Draghici
  • Adrian Beteringhe
  • Titus Constantinescu
  • Mircea D. Banciu
  • Alexandru T. Balaban


An interesting observation was made when studying the S N Ar reaction between several 4-aryloxy-7-nitrobenzofurazans (2) and several amino acids leading to the apparition of detectable fluorescence from the substitution products3. Acidic amino acids reacted very slowly=while basic amino acids react fastest with2 having an unsubstituted phenyl or a 4-formyl-phenyl Ar group. Amongst neutral amino acids, proline reacts fastest at room temperature after 100 min. With2 having a methoxy-subtituted Ar group.


4-Aryloxy-7-nitrobenzofurazans amino acids SNAr reaction fluorescence 


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Copyright information

© Central European Science Journals 2004

Authors and Affiliations

  • Marioara Bem
    • 1
  • Marilena Vasilescu
    • 2
  • Miron T. Caproiu
    • 3
  • Constantin Draghici
    • 3
  • Adrian Beteringhe
    • 1
  • Titus Constantinescu
    • 1
  • Mircea D. Banciu
    • 4
  • Alexandru T. Balaban
    • 5
  1. 1.Laboratory of Supramolecular Chemistry and Interphase ProcessesInstitute “I.G. Murgulescu” of Physical Chemistry of Roumanian AcademyBucharestRoumania
  2. 2.Structure LaboratoryInstitute “I.G. Murgulescu” of Physical Chemistry of Roumanian AcademyBucharestRoumania
  3. 3.Institute “C.D. Nenitzescu” of Organic ChemistryRomanian AcademyBucharestRoumania
  4. 4.Department of Organic Chemistry“Politehnica” University BucharestBucharestRoumania
  5. 5.Department of Marine SciencesTexas A & M University at GalvestonGalvestonUSA

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