| Texto completo | |
| Autor(es): |
Augusto, Felipe A.
[1]
;
Bartoloni, Fernando H.
[2, 1]
;
Cabello, Maidileyvis C.
[1]
;
dos Santos, Ana Paula F.
[1]
;
Baader, Wilhelm J.
[1]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Sao Paulo - Brazil
[2] Univ Fed ABC, Ctr Ciencias Nat & Humanas, Santo Andre - Brazil
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY; v. 382, SEP 1 2019. |
| Citações Web of Science: | 1 |
| Resumo | |
The peroxyoxalate reaction, base catalyzed perhydrolysis of activated aromatic oxalate esters in the presence of chemiluminescence activators, has widespread analytical and bioanalytical applications and is one of the most efficient chemiluminescence transformations known. We report here a kinetic study on this reaction using 2,6-lutidine as catalyst in organic (1,2-dimethoxyethane) and aqueous medium. In both media, experimental conditions can be designed which lead to reproducible results important for analytical applications. Observed rate constants (determined by observing the light emission intensity as well as absorbance variation due to phenol releases) show dependence on both the 2,6-lutidine and the hydrogen peroxide concentration, indicating their participation in the rate-limiting step of the transformation. The rate constants obtained from these kinetic studies proved to be at least one order of magnitude higher in water than in 1,2-dimethoxyethane as solvent. Kinetic experiments designed to distinguish between three different types of catalysis (nucleophilic, specific base and general base catalysis) clearly indicate that the role of 2,6-lutidine in this reaction is as general base catalyst in water as well as most likely in organic medium. (AU) | |
| Processo FAPESP: | 14/22136-4 - Uso de solventes verdes e suas misturas na otimização de processos químicos |
| Beneficiário: | Omar Abou El Seoud |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 12/13807-7 - Novas ferramentas para o estudo de reações de transferência de elétron em sistemas modelo do PS II |
| Beneficiário: | Fernando Heering Bartoloni |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |