Organic diphenylanthracene

Figure 16.4 Structural formulae of polyaromatic hydrocarbons—brightness organic ECL luminophores blue emissive 9,10-diphenylanthracene, green emissive 5,12-diphenylnaphtha-cene, orange emissive 5,6,11,12-tetraphenylnaphtacene (RUB), and red emissive bis-4,4 -(7,12-dipheny l)-benzo [k] fluoranthene.

In organic ECL reactions, the luminescent species are generally derivatives of polyaromatic hydrocarbons where A and B in Eqs. (1) through (4) can be either the same species (leading to self-annihilation) or two different PAHs with either being the analyte (mixed system). Some examples of both self-annihilation and mixed system ECL reactions of organic molecules are listed in Tables 1 and 2. One well-studied example is the self-annihilation reaction between the anion and cation radicals of 9,10-diphenylanthracene (DPA) via an S-route in acetonitrile resulting in blue fluorescence characteristic of DPA [17] ... 

Aromatic hydrocarbons, with the reaction scheme as described above, play the same key role in ECL studies as in organic electrochemistry and organic UV-VIS spectroscopy. 5,6,11,12-Tetraphenyltetracene (rubrene) and 9,10-diphenylanthracene (DPA) are the most notable examples (Fig. 10). The stability of their radical ions, with the quantum efficiency of the parent molecules near unity, [121] has fascinated many ECL investigators since the 1960s ([122,123] and cited references). Taking into account the fact that other aromatic hydrocarbons usually do not form stable... 

Zhivnov et al. have obtained similar increase in the intensity of ECL under ultrasound from a 9,10-diphenylanthracene system [213], The ECL intensity of 9,10-diphenylanthracene in DMF solutions under sonication was increased by factors of20-30 depending on the concentration of the solutions, ultrasound power, and frequency. The same authors also studied the acoustic field effect on ECL of several organic molecules in solutions [214] and obtained similar results for the following ECL molecules l,5-diphenyl-3-styrylpyrazoline, rubrene, 9,10-diphenylanthracene, 9,10-dimethylanthracene, and perylene. 

Disubstituted anthracenes, such as 9,10-dichloroanthracene (v) and 9,10-diphenylanthracene (vi), follow a simple electron-transfer (E) reaction mechanism in [C2mim][N(Tf)2] with no homogeneous reactions [9], which is consistent with previous observations in organic solvent systems [11],... 

Organic ECL luminophores includes luminol (2,3-amino-phthalhydrazide), ABEI (Af-(4-aminobutyl)-Af-ethyliso-luminol), lucigenin N, Af -dimethyl-9,9-bisacridinium), 9,10-diphenylanthracene (DPA), RUB (rubrene), diimides and various other organic confounds. 

One of the earliest examples of electron transfer leading to chemiluminescence in an organic reaction was reported in 1964 by Chandross and Sonntag [5]. The radical anion of diphenylanthracene (DPA), produced by reaction with potassium metal, was oxidised by 9,lO-dichloro-9,10-diphenyl anthracene (DPACy. Chemiluminescence with a spectrum identical to that of DPA fluorescence was observed. 

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