Anthracene-9-carboxylate

Hydrogen and sodium do not react at room temperature, but at 200—350°C sodium hydride is formed (24,25). The reaction with bulk sodium is slow because of the limited surface available for reaction, but dispersions in hydrocarbons and high surface sodium react more rapidly (7). For the latter, reaction is further accelerated by surface-active agents such as sodium anthracene-9-carboxylate and sodium phenanthrene-9-carboxylate (26—28). 

The first quantitative study of the reaction was carried out with anthracene-9-carboxylic acid (which possesses the necessary steric requirement by virtue of the peri-hydrogen atoms, and is very reactive at the 9 position towards electrophilic substitution). Schenkel632 found that the decarboxylation rate was increased in the presence of acid, and the first-order rate coefficients (believed to be in sec-1) are given in Table 205. It was subsequently concluded that in the absence of acid,... 

The receptor-operated Cl -channels of the central nervous system (CNS) are gated by the respective agonists GABA and glycine. Most Cl -channels can be inhibited by disulphonate stilbenes. Muscle Cl -channels can be inhibited by anthracene-9-carboxylate (A9C) and probably by IAA-94. The ICOR Cl -channel is fairly sensitive to NPPB. It should be noted, however, that none of these probes, except for the GABA- and glycine-receptor Cl -channels, is of sufficient affinity and selectivity to permit the channel identification by its use. This dilemma is one of the reasons why the purification of epithelial Cl -channels lags behind that of the CNS Cl -channels. 

Table 5 Effect of Anion-Channel Antagonists (Anthracene-9-carboxylic acid, ethacrynic acid each 100 fiM) and of Brefeldin A (Exocytosis Inhibitor 45 fiM) on Release of Phytosiderophores from Roots of Fe-Deficient Barley and Mai/.e...

The same nonpolar conformation can be achieved by conversion to bicyclic structures. 1,4-Cyclo-addition of ethylene to anthracene-9-carboxylic acid gives acid 68. Successive conversion to the N-methylamide, via the acid chloride, followed by reduction with lithium aluminum hydride produced... 

Sodium anthracene-9-carboxylate, 22 765 Sodium antimonide, 3 54, 3 58 Sodium ascorbate, 25 804... 

Kamat, RV. 1989. Photoelectrochemistry in particulate systems 9. Photosensitized reduction in a colloidal TiOj system using anthracene-9-carboxylic acid as the sensitizer. J Phys Chem 93 859-864. 

Partial reduction of the aromatic ring is especially easy in anthracene-9-carboxylic acid which was reduced to 9,10-dihydroanthracene-9-carboxylic acid with 2.5% sodium amalgam in aqueous sodium carbonate at 10° in 80% yield [987]. Aromatic carboxylic acids with hydroxyl groups in the ortho positions suffer ring cleavage during reductions with sodium in alcohols and are converted to dicarboxylic acids after fission of the intermediate j8-keto acids. 

Anthracene-9-carboxylic acid [723-62-6] M. 222.2, m 214 (dec). Crystd from EtOH. 

Figure 7.30 (a) Microdensitometer records of a photographic plate showing the absorption of the triplet state of anthracene-9-carboxylic acid. Horizontal axis, wavelength in nm vertical axis, absorbance, (b) Oscilloscope trace of the absorption of the ketyl radical of benzophenone in ethanol, (c) Second-order plot of the decay kinetics against time t... 

Dyes such as erythrosin B [172], eosin [173-177], rose bengal [178,179], rhodamines [180-185], cresyl violet [186-191], thionine [192], chlorophyll a and b [193-198], chlorophyllin [197,199], anthracene-9-carboxylate [200,201], perylene [202,203] 8-hydroxyquinoline [204], porphyrins [205], phthalocyanines [206,207], transition metal cyanides [208,209], Ru(bpy)32+ and its analogs [83,170,210-218], cyanines [169,219-226], squaraines [55,227-230], and phe-nylfluorone [231] which have high extinction coefficients in the visible, are often employed to extend the photoresponse of the semiconductor in photoelectro-chemical systems. Visible light sensitization of platinized Ti02 photocatalyst by surface-coated polymers derivatized with ruthenium tris(bipyridyl) complex has also been attempted [232,233]. Because the singlet excited state of these dyes is short lived it becomes essential to adsorb them on the semiconductor surface with... 

Anthracene, at 180-200 "C, gave some anthracene-9-carboxylic acid chloride (10.1) on reaction with COClj in the presence of aluminium(III) chloride [811a], whilst at 240-250 C, lO-chloroanthracene-9-carboxylic acid chloride (10.2) was formed [153b]. 

Anthracene-9-carboxylic acid (anthroic acid) [723-62-6] M 222.2, m 214 (dec), pK 3.65. Crystallise the acid from EtOH. It is fluorescent in EtOH. [Beilstein 9IV 2671.]... 

In the case of double salts of anthracene-9-carboxylic acid (9-AC), which usually cyrstallized with included water and/or solvent, the 9-AC" component in the crystal underwent decarboxylation and reduction along with dimerization (Scheme 45) [77]. Although the head-to-tail dimer and a mixed dimer were obtained, the head-to-head one was not produced. The reactivity was influenced by the amount of the included solvenL e.g., (9-AC )2(c-chxiiH2 )(EtbH)xi was photostable, while (9-AC )2(c-chxnH2 )(EtOH)o,5 gave six photoproducts. Incidentally, the elusive head-to-head dimer was selectively obtained by solid-state irradiation of the 9-AC homocrystal as a thermally unstable product [78]. 

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