Kinetic studies on the chemiluminescent decomposition of an isolated intermediate in the peroxyoxalate reaction

Stevani, Cassius V.; Baader, W. J.

doi:10.1002/(sici)1099-1395(199708)10:8<593::aid-poc926>3.0.co;2-h

Cited by 38 publications

(32 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The mechanism for the peroxyoxalate reaction with general base catalysis by phosphate consists in rate-limiting hydrogen peroxide attack on the ester carboxylic group assisted by monohydrogen phosphate (HPO 4 À ), the prominent species in slightly basic conditions (pH = 8). The initially formed tetrahedral intermediate should be transformed in a fast reaction to the corresponding peroxalic acid derivative (Scheme 3), [44,45] which undergoes fast intramolecular base catalyzed cyclization to the high-energy intermediate, supposed to be, 1,2-dioxetanedione, the peroxidic dimer of carbon dioxide. [10,46,47] This intermediate interacts with the activator (ACT) in a very fast transformation, which cannot be observed by conventional kinetic measurements, however, it is known that it should involve electron transfer and electron back-transfer steps between the peroxide and the ACT leading ultimately to the formation of the ACT's electronically excited singlet state and consequent fluorescence emission which constitutes the emission of chemiluminescence from the reaction, utilized here to follow the reaction kinetics (Scheme 3).…”

Section: Discussionmentioning

confidence: 99%

General Acid and Base Catalysis by Phosphate in Peroxyoxalate Chemiluminescence

et al. 2016

Self Cite

View full text Add to dashboard Cite

The peroxyoxalate reaction, one of the most efficient chemiluminescent transformations, is widely utilized in analytical and bioanalytical assays. Although the mechanism of this transformation has been extensively studied, it is still not yet fully clarified. Furthermore, no detailed mechanistic studies have been performed in aqueous media, highly important for analytical applications. The light emission kinetic behaviour of the peroxyoxalate reaction is studied here in phosphate buffered binary 1,2-dimethoxyethane/water mixtures at different pH values using three oxalic ester derivatives. The results indicate that conditions can be found where the chemiluminescent perhydrolysis is predominant over dark ester hydrolysis; the reactions are subject to general acid and base catalysis by phosphate ions; are reasonably reproducible, although, generally fast. However, chemiluminescence emission quantum yields are much lower than in organic solvents.

show abstract

Section: Discussionmentioning

confidence: 99%

General Acid and Base Catalysis by Phosphate in Peroxyoxalate Chemiluminescence

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…115,116 Entretanto, uma vez sintetizado e caracterizado, por Stevani et al, 117,118 o O,O-hidrogênio monoperóxi-oxalato de 4-clorofenila, derivado do perácido 11 (Ar = p-Cl-C 6 H 4 ) não demonstrou interação direta com ACTs, um fato que exclui, de maneira definitiva, espécies do tipo 11 como intermediários de alta energia na reação peróxi-oxalato. Por outro lado, o composto preparado exibe quimiluminescência em presença de um ACT e de bases com pK a adequado (pK a > 6) (Esquema 9), o que sugere a ocorrência de uma reação química anterior à emissão, provavelmente, uma ciclização originando o IAE.…”

Section: 99unclassified

Luz: um raro produto de reação

et al. 2011

View full text Add to dashboard Cite

Recebido em 18/6/10; publicado na web em 30/11/10 LIGHT: A RARE REACTION PRODUCT. The production of visible light by chemical reactions constitutes interesting and fascinating phenomena and several reaction mechanisms are discussed to rationalize excited state formation. Most efficient chemiluminescence reactions are thought to involve one or more electron transfer steps and chemiexcitation is believed to occur by radical annihilation. A brief introduction to the general principles of light production and the main known chemiexcitation mechanisms will be given here. Subsequently, recent results on the mechanistic elucidation of efficient chemiluminescence systems, as the peroxyoxalate reaction, the induced decomposition of phenoxy-substituted 1,2-dioxetanes and the catalyzed decomposition of new a-peroxylactones will be discussed.Keywords: chemiluminescence; excited states; organic peroxides. HISTÓRICO DAS REAÇÕES QUIMILUMINESCENTESA quimiluminescência ou, em outras palavras, o processo de emissão de luz como produto ou um dos produtos de uma reação química, é um dos fenômenos mais exuberantes da Química, ao mesmo tempo em que é um dos mais incompreendidos do ponto de vista do "como". Como uma reação química é capaz de "acender", uma vez que certos reagentes foram misturados? Tal tipo de reação ainda pode ocorrer em organismos vivos, sendo atribuído o nome de bioluminescência, fenômeno esse que foi capaz de atrair a atenção do próprio Aristóteles, que descreveu a observação de uma "luz fria" emitida por vaga-lumes.1 Inclusive, foram os próprios gregos os responsáveis por dar o nome de "vaga-lume" aos insetos que aparentavam ser faíscas perambulando noite adentro. 1Mesmo sabendo que observações da emissão de luz a partir de reações e seres vivos são tão antigas, não há informações acerca de quem descobriu tais eventos, ou mesmo aonde. Sabe-se, entretanto, que Wiedemann foi o primeiro a reportar de maneira documentada uma definição para quimiluminescência: "Das bei chemischen Prozessen auftretende Leuchten würde Chemilumineszenz genannt", 2 o mesmo proferiu em 1888, que pode ser traduzido como "a emissão observada durante processos químicos deve ser chamada de quimiluminescência". Wiedemann propôs tal classificação utilizando como base o trabalho realizado por Radziszewski, mais de uma década antes, que observou uma intensa emissão de luz proveniente da autoxidação da lofina (2,4,5-trifenilimidazol, 1, Esquema 1), sendo que tal transformação não ocorria quando o aquecimento era realizado na ausência de oxigênio.3 Importante notar que é na publicação de Wiedemann que o mesmo propõe uma diferenciação entre a quimiluminescência e o fenômeno de emissão de luz devido a um aumento de temperatura, a incandescência, um processo físico, não químico, decorrente da emissão de radiação pelo corpo negro.

show abstract

“…Of the numerous chemiluminescence reactions known to date, peroxyoxalate chemiluminescence (PO-CL) is the most effective one (1)(2), which has been extensively investigated since its discovery by Chandross (3) and practically used not only as a light source, but also in the field of analytical chemistry. A typical PO-CL (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) consists of the reaction of the active oxalates, such as bis(2,4,6trichlorophenyl) oxalate (TCPO) (4) and hydrogen peroxide, in which light emits from the excited states of the externally added fluorescent activators. In the peroxyoxalate system, 1,2-dioxetanones (20), including a 1,2-dioxetanedione (1,2,19,21,22) and some cyclic peroxides (23)(24)(25)(26) have been suggested as the highenergy key intermediates capable of producing an excited species by their thermal decomposition according to a chemically initiated electron exchange luminescence (CIEEL) process (27)(28)(29) (Scheme 1).…”

Section: Introductionmentioning

confidence: 99%

Unprecedented chemiluminescence behaviour during peroxyoxalate chemiluminescence of oxalates with fluorescent or electron‐donating aryloxy groups

et al. 2006

View full text Add to dashboard Cite

A series of diaryl and bis(4-styrylphenyl) oxalates with electron-donating substituents or fluorescent moieties were subjected to the peroxyoxalate chemiluminescence (PO-CL) reaction, some of which were found to behave in a unprecedented manner. The reaction of bis(p-methyoxyphenyl) oxalate, as a representative example, emits light due not only to the emission from the externally added excited fluorophore, but also from the presumable excimer of p-methoxyphenol. Also, during the reaction of the bis(4-styrylphenyl) oxalates, the emission based on the fluorescence as well as the excimer of the eliminating group were observed. These experimental results suggest that such emitting species would be formed by an intra- and intermolecular electronic interaction with a high-energy intermediate, such as a dioxetanone.

show abstract

Kinetic studies on the chemiluminescent decomposition of an isolated intermediate in the peroxyoxalate reaction

Abstract: The peroxyoxalate system undergoes one of the most efficient chemiluminescence reactions and is the only one considered to involve an intermolecular chemically initiated electron exchange luminescence mechanism, with proven high efficiency.

Cited by 38 publications

References 21 publications

General Acid and Base Catalysis by Phosphate in Peroxyoxalate Chemiluminescence

General Acid and Base Catalysis by Phosphate in Peroxyoxalate Chemiluminescence

Luz: um raro produto de reação

Unprecedented chemiluminescence behaviour during peroxyoxalate chemiluminescence of oxalates with fluorescent or electron‐donating aryloxy groups

Contact Info

Product

Resources

About