Anthracene yellow

Acid alizarine yellow, eriochrome yellow, eriochrome phosphine, alizarine yellow G, G, 3 G, R, flavazol, diamond flavine, anthracene yellow, alizadine yellow, chrome fast yellow, fast mordant yellow, salicine yellow D, diamond yellow, chrome yellow, chrome orange, etc. 6. 9 hi s Mordant present. Boll with 5 per cent, sodium acetate and a piece of white cotton for two minutes. Decolorised. Colour is not 1 air or by persulphate Axo mordant (Cr... 

A dibrominated dioxy-j8-methylcoumarine is known commercially as Anthracene Yellow. 

Dehydrogenation may also be accompanied by molecular condensation, as is the case when two molecules of benzene form diphenyl or two molecules of toluene form stilbene or when methylanthraquinone is converted to anthracene yellow C. 

Identification of Aromatic Hydrocarbons. Picric acid combines with many aromatic hydrocarbons, giving addition products of definite m.p. Thus with naphthalene it gives yellow naphthalene picrate, C oHg,(N08)jCeHiOH, m.p. 152°, and with anthracene it gives red anthracene picrate, C 4Hio,(NOj)jCeHjOH, m.p. 138 . For practical details, see p. 394. 

Naphthalene, CioHs, colourless solid, m.p. 80°, insoluble in water, soluble in alcohol, characteristic odour. Anthracene, CjH4 C2H2 CjH4, m.p. 216°, white crystals when pure, with a faint blue fluorescence, but often very pale yellow crystals insoluble in water, slightly soluble in alcohol. Phenanthrene, m.p. 98°, and biphenyl, m.p. 69°, are white solids. 

Purification of anthracene. Dissolve 0-3 g. of crude anthracene (usually yellowish in colour) in 160-200 ml. of hexane, and pass the solution through a column of activated alumina (1 5-2 X 8-10 cm.). Develop the chromatogram with 100 ml. of hexane. Examine the column in the hght of an ultra-violet lamp. A narrow, deep blue fluorescent zone (due to carbazole, m.p. 238°) will be seen near the top of the column. Immediately below this there is a yellow, non-fluorescent zone, due to naphthacene (m.p. 337°). The anthracene forms a broad, blue-violet fluorescent zone in the lower part of the column. Continue the development with hexane until fluorescent material commences to pass into the filtrate. Reject the first runnings which contain soluble impurities and yield a paraffin-hke substance upon evaporation. Now elute the column with hexane-benzene (1 1) until the yellow zone reaches the bottom region of the column. Upon concentration of the filtrate, pure anthracene, m.p. 215-216°, which is fluorescent in dayhght, is obtained. The experiment may be repeated several times in order to obtain a moderate quantity of material. 

Qumones are colored p benzoqumone for example is yellow Many occur natu rally and have been used as dyes Alizarin is a red pigment extracted from the roots of the madder plant Its preparation from anthracene a coal tar derivative m 1868 was a significant step m the development of the synthetic dyestuff industry... 

Dibenz[yellow-green colour (due to other pentacyclic impurities) has been removed by crystn from benzene or by selective oxidation with lead tetraacetate in acetic acid [Moriconi et al. J Am Chem Soc 82 3441 7960]. 

Dissolve naphthalene in a little spirit, and add an equal quantity of a solution of picric acid in spirit. On cooling, yellow needles of naphthalene picrate separate, C,oHg.CQH20H(NO,)3. Benzene forms colourless crystals, anthracene, scarlet needles, having a similar composition. Sec Appendix, p. 295. 

The first such compound to be prepared was the deep-yellow unstable compound 9-arsa-anthracene but the thermally stable colourless arsabenzene (arsenin) can now conveniently be made by a general route from l,4-pentadiyne ... 

Equimolar amounts of anthracene,/ -benzoquinone, and aluminum chloride give the faintly yellow adduct in 15 minutes. The product is unstable to heat turning yellow at 207°, turning red at 210°, and slowly charring. When 2 molar equivalents of anthracene are used, the bis adduct is obtained, mp 230°, unobtainable in the absence of the catalyst. 

In a dry, 1-1., two-necked flask, equipped with a mechanical stirrer and a reflux condenser fitted with a drying tube, are placed 17.8 g. (0.100 mole) of anthracene (Note 1), 27.2 g. (0.202 mole) of anhydrous cupric chloride (Note 2), and 500 ml. of carbon tetrachloride (Note 3). The reaction mixture is stirred and heated under reflux for 18-24 hours. The brown cupric chloride is gradually converted to white cuprous chloride, and hydrogen chloride is gradually evolved. At the end of the reaction the cuprous chloride is removed by filtration, and the carbon tetrachloride solution is passed through a 35-mm. chromatographic column filled with 200 g. of alumina (Note 4). The column is eluted with 400 ml. of carbon tetrachloride. The combined eluates are evaporated to dryness to give 19-21 g. (89-99%) of 9-chloroanthracene as a lemon-yellow solid, m.p. 102-104° (Note 5). Crystallization of the product from petroleum ether... 

Stilbeneamines. The functionalization of stilbenes with arylamino groups leads to materials that emit in the green-to-yellow spectral region. For example, 9,10-bis(4-(7V,/V-diphenylamino)styryl-anthracene (BSA, 21) absorbs at429nm and emits at 585 nm [141]. Compound 21 and other derivatives of bistyrylanthra-cene have been successfully applied in yellow emitting OLEDs [64]. Tetra(tri-phenylamino)ethylene (TTPAE, 20) emits at 539 nm [109]. The latter compound exhibits a large quantum yield of 25% in the amorphous film, but does not show fluorescence in solution. 

In this manner de Koe, van Veen andBickelhaupt [33,34,35] were able to prepare the very unstable 9-phosphaphenanthrene 37 as well as 9-phospha-anthracene 41a, These compounds were stored in solution and could not be isolated as solids.However, if the C-10 position of 41 is blocked by a phenyl group, the same procedure leads to the much more stable yellow crystalline, 10-phenyl-9-phospha-anthracene 41b (4-phenyl-dibenzo[b, e]-phosphorin) (m. p. 173—176 °C). Another stable substituted phosphaphenanthrene 43 has been prepared (a/he/t in... 

If one of the substances has a known fluorescence efficiency, the value of the other is then simply obtained. Convenient standard solutions are rhodamine B in ethanol with fluorescence in the yellow and efficiency 0.69, quinine bisulfate in 0.1 N sulfuric acid with fluorescence in the blue and efficiency 0.55. anthracene in ethanol with fluorescence in the violet and efficiency 0.27 in the ultraviolet region, naphthalene ( = 0.19), phenol (0 = 0.19), or benzene (0 = 0.042) can be used. With the last four compounds the solution must be deaerated by passing a current of nitrogen before measurement. To minimize the effect of errors in the spectral sensitivity curve it is desirable to use as the standard a solution... 

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