| Texto completo | |
| Autor(es): |
Ciscato, Luiz Francisco M. L.
[1, 2]
;
Bartoloni, Fernando H.
[1]
;
Weiss, Dieter
[2]
;
Beckert, Rainer
[2]
;
Baader, Wilhelm J.
[1]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, BR-05508000 Sao Paulo - Brazil
[2] Univ Jena, Inst Organ Chem & Makromol Chem, D-07743 Jena - Germany
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Organic Chemistry; v. 75, n. 19, p. 6574-6580, OCT 1 2010. |
| Citações Web of Science: | 38 |
| Resumo | |
The activation parameters for the thermal decomposition of 13 acridinium-substituted 1,2-dioxetanes, bearing an aromatic moiety, were determined and their chemiluminescence emission quantum yields estimated, utilizing in situ photosensitized 1,2-dioxetane generation and observation of its thermal decomposition kinetics, without isolation of these highly unstable cyclic peroxides. Decomposition rate constants show linear free-energy correlation for electron-withdrawing substituents, with a Hammett reaction constant of rho = 1.3 +/- 0.1, indicating the occurrence of an intramolecular electron transfer from the acridinium moiety to the 1,2-dioxetane ring, as postulated by the intramolecular chemically initiated electron exchange luminescence (CIEEL) mechanism. Emission quantum yield behavior can also be rationalized on the basis of the intramolecular CIEEL mechanism, additionally evidencing its occurrence in this transformation. Both relations constitute the first experimental evidence for the occurrence of the postulated intramolecular electron transfer in the catalyzed and induced decomposition of properly substituted 1,2-dioxetanes. (AU) | |
| Processo FAPESP: | 05/58320-4 - Efeito da estrutura e do meio de reação sobre a quimiluminescência de dioxetanonas |
| Beneficiário: | Fernando Heering Bartoloni |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado Direto |