Generation and conversions of aromatic amine radical cations in acid zeolites

H. García, V. Martí, I. Casades, V. Fornés, H. D. Roth

Research output: Contribution to journalArticlepeer-review

24 Scopus citations


Incorporation of aromatic amines, including diphenylamine (DPA), carbazole (Cbz), diphenylbenzidine (DPB) and benzidine (Bzd), into acid zeolites generated the corresponding radical cations, DPA·, Cbz·, DPB· and Bzd·, as indicated by comparison of the characteristic long-wavelength diffuse reflectance spectra with spectra observed in solution. Samples of DPA· sequestered in HZSM-5 are deprotonated; the resulting diphenylaminyl radical, DPN·, is remarkably stable; diffuse reflectance or EPR spectra show that a significant population persists for longer than four years. In contrast, DPA· adsorbed within HY zeolite, undergoes a clean conversion to Cbz·. Non-acidic zeolites devoid of Brønsted and Lewis sites failed to generate radical cations to an extent detectable spectroscopically; these results clearly indicate that Brønsted and/or Lewis sites are responsible for the observed oxidation.

Original languageEnglish (US)
Pages (from-to)2955-2960
Number of pages6
JournalPhysical Chemistry Chemical Physics
Issue number14
StatePublished - 2001
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry


Dive into the research topics of 'Generation and conversions of aromatic amine radical cations in acid zeolites'. Together they form a unique fingerprint.

Cite this