The stability of arylpentazoles
2004 (English)In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 108, no 36, 7463-7467 p.Article in journal (Refereed) Published
The stability of phenylpentazole along with para-substituted and ortho,para-substituted arylpentazoles have been studied using high-level density functional theory (DFT). The decomposition of arylpentazoles to N-2 and the corresponding azide is a first-order reaction, where the breaking of the N1-N2 bond is concomitant with cleavage of the N3-N4 bond. Calculations confirm that the stability of arylpentazoles increases with electron-donating groups and decreases with electron-withdrawing groups, in the para position, as found in experiments. The stabilizing effect of the electron-donating groups is shown to be due to a resonance interaction with the electron-withdrawing pentazole ring. Addition of solvation effects, using the polarizable continuum model to simulate the polar solvent methanol, increases the stability of arylpentazoles. This is due to a more polar ground state than transition state. The calculated free energies of activation for the arylpentazoles agree well with experimental results. From the calculations, the electron-withdrawing effect of the pentazole group is found to be similar to that of cyanide (-CN). Some new arylpentazoles with hydroxyl groups in the ortho position are proposed. These are predicted to be more stable than all previously synthesized neutral arylpentazoles.
Place, publisher, year, edition, pages
2004. Vol. 108, no 36, 7463-7467 p.
polarizable continuum model, pentazolate anion, polynitrogen chemistry, bonding analysis, ab-initio, aryldiazonium, cyclo-n-5(-), ionization, mechanism, molecules
IdentifiersURN: urn:nbn:se:kth:diva-23701DOI: 10.1021/jp0484480ISI: 000223703600017ScopusID: 2-s2.0-4544343944OAI: oai:DiVA.org:kth-23701DiVA: diva2:342400
QC 201109162010-08-102010-08-102016-06-01Bibliographically approved