Coumarin derivatives, hydrogen peroxide

Weak to moderate chemiluminescence has been reported from a large number of other Hquid-phase oxidation reactions (1,128,136). The Hst includes reactions of carbenes with oxygen (137), phenanthrene quinone with oxygen in alkaline ethanol (138), coumarin derivatives with hydrogen peroxide in acetic acid (139), nitriles with alkaline hydrogen peroxide (140), and reactions that produce electron-accepting radicals such as HO in the presence of carbonate ions (141). In the latter, exemplified by the reaction of h on(II) with H2O2 and KHCO, the carbonate radical anion is probably a key intermediate and may account for many observations of weak chemiluminescence in oxidation reactions. 

Certain fluorescent compounds, such as the coumarin derivative, scopoletin, can act as hydrogen donors in the oxidative reaction catalysed by horseradish peroxidase (Udenfriend, 1969), an enzyme that exhibits substrate specificity for hydrogen peroxide... 

Among different coumarin derivatives used, 7-Amino-4-trifluoromethylcoumarin (ATFMC) revealed the most promising characteristics as an efficient fluorescent emitter. AFTMC is used in the synthesis of a substrate for fluorimetric assay of proteolytic enzymes and for use as a laser dye. We have recently investigated the chemiluminescence reactions of some peroxyoxalate esters, hydrogen peroxide and AFTMC. In this paper we report the solvent effects on the kinetics of the chemiluminescence process of the peroxyoxalate chemiluminescence in the presence of AFTMC. 

Chaichi MJ, Karami AR, Shockravi, A, Shamsipur M. Chemiluminescence characteristics of coumarin derivatives as blue fluorescers in peroxyoxalate-hydrogen peroxide system Spectrochim Acta Part A 2003 59 1145-50. 

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