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Crocein Acid

Schaffer s acid, CioHg04S. 2-hydroxy-7-naphthalene sulphonic acid. Obtained by sulphonating 2-naphthol with a small amount of sulphuric acid at a higher temperature than is used for the preparation of crocein acid. A valuable dyestuff intermediate. [Pg.353]

The first product formed by the actio of concentrated sulfuric acid on/3-naphthol is 2-naphthol-l-sulfonic acid (page 199). This compound, however, is very unstable and rearranges, even in the cold, in the presence of excess sulfuric acid, to form 2-naphthol-8-sulfonic acid (Bayer acid, croceine acid), and this in turn rearranges, only partially in the cold but completely at higher temperatures, into 2-naphthol-6-sulfonic acid (Schaeffer acid). [Pg.111]

One of these (the a-sulphonic acid or crocein-acid) is best obtained at a low temperature. By further heating with sulphuric acid it goes over into the )9- or Schaeffer s acid, which was prepared by Schaeffer a long time ago. These acids are distinguished... [Pg.50]

The acid soluble in alcohol and salt-solution (G-acid of Meister, Lucius, and Briining, 7-acid of Cassella and Co.) behaves very like, /3-naphthol-a-monosulphouic acid (crocein acid), and must be regarded as a derivative of the latter, as it is formed quantitatively on further sulphonation of crocein acid., It may also be obtained from Schaeffer s acid (this is contradicted by some chemists), and Armstrong gives it the following formula —... [Pg.52]

By the action of concentrated sulphuric acid on y3-naphthyl-amine two monosulphonic acids are first formed, 9-naphthylaminc-a-sulphonic acid (corresponding to the crocein acid from -naph-thol), and the yS-naphthylamine-7-sulphonic acid. [Pg.69]

Diazot. Aniline + croceine acid (0-NaphthdL sulphonic acid)... [Pg.233]

Two important monosulfonic acids result ing from the sulfonation of 2-naphthol are Schaeffer s acid and Crocein acid. At 100°C, Schaeffer s acid is preponderant at lower temperatures more Crocein acid is formed. [Pg.884]

Fig. 3.130. HPLC chromatograms of the test mixture detected by DAD (270 nm, upper lane) by APCI-MS-TIC (middle) and by ESI-MS-TIC (lower lane). Peak identification l=benzene sulphonic acid sodium salt 2=2-naphtalene sulphonic acid sodium salt 3=2-anthraquinone sulphonic acid sodium salt 4 = sulphorhodamine D sodium salt 5=crocein orange G 6=eriochrome black T 7=2,6-anthraquinone disulphonic acid disodium salt 8 = 1,5-naphtalene disulphonic acid disodium salt 9 = azophloxine 10 = 1,2-benzene disulphonic acid dipotassium salt. Reprinted with permission from G. Socher et al. [178]. Fig. 3.130. HPLC chromatograms of the test mixture detected by DAD (270 nm, upper lane) by APCI-MS-TIC (middle) and by ESI-MS-TIC (lower lane). Peak identification l=benzene sulphonic acid sodium salt 2=2-naphtalene sulphonic acid sodium salt 3=2-anthraquinone sulphonic acid sodium salt 4 = sulphorhodamine D sodium salt 5=crocein orange G 6=eriochrome black T 7=2,6-anthraquinone disulphonic acid disodium salt 8 = 1,5-naphtalene disulphonic acid disodium salt 9 = azophloxine 10 = 1,2-benzene disulphonic acid dipotassium salt. Reprinted with permission from G. Socher et al. [178].
Both these sulphonic acids of amidoazobenzene, and especially the disulphonic acid, are valuable yellow dyestuffs, and the sodium salt of the latter comes into commerce as Acid Yellow or Fast Yellow. A further application of these acids is in the preparation of tetrazo-dyestuflFs, for example Biebrich- and Crocein-scarlets. [Pg.36]

From the facts that azo-dyes from Schaeffer s acid differ but little in shade and solubility from those obtained from -naphthol, and that simple /3-naphthol azo-compounds on sulphonation always yield derivatives of Schaeffer s acid, and never those of crocein-acidj it may naturally be concluded that the azo-group enters in the same position both in /S-naphthol and in Schaeffer s acid. This is the a-y position. [Pg.51]

The sulphonic acids of this compound come into commerce as Biebrich and Crocein scarlets, according to the position of the sulpho-group. [Pg.64]

This body [61] is known as CroceTn Scarlet 3B, and although not producing fast shades is used, in cotton-dyeing. Crocein Scarlet 7 B is a dyestuff of somewhat bluer shade, and is obtained from orthoamidoazotoluenesulphonic acid in the same manner. The tetrazo-dyes prepared from y3-naphthol- -sulphonic acid give soluble crystalline calcium salts, while those from the other acid give amorphous and insoluble calcium salts. [Pg.65]

Broenner acid Casella s acid Chicago acid (SS acid) chromotropic acid Cleve s acid crocein (Bayer s acid) epsilon acid G acid... [Pg.115]

Biebrich scarlet was discovered in 1878/9, a very pure red disazo dye said originally to rival cochineal in brightness . It is described by Zerr and Riibencamp (1906). Synonyms include Ponceau Biebrich Scarlet, Cl 26905/Acid Red 66, Croceine Scarlet and Double Scarlet BSF. Now principally used as a histological stain. [Pg.45]

Brilliant acid red G, see A-00476 Brilliant basic blue R, see A-00452 Brilliant blue 9, see E-00018 Brilliant blue C, see B-00477 Brilliant carmoisine, see A-00477 Brilliant chrome blue P, see G-00005 Brilliant Congo blue BFL, B-00476 Brilliant cresyl blue, B-00477 Brilliant croceine, B-00478 Brilliant green, B-00479... [Pg.983]

Chromotrope F4B, C-00292 Brilliant croceine, B-00478 > Polyethylene glycol, P-00247 a-Oxobenzeneacetic acid, see 0-00055... [Pg.1198]

Brilliant croceine Di-Na salt, in B-00478 3-[(6-Bromo-2-benzothiazolyl)azo]-4,5-dihydroxy-2,7-naphthalenedisulfonic acid, B-00490... [Pg.1299]

See other pages where Crocein Acid is mentioned: [Pg.260]    [Pg.501]    [Pg.1051]    [Pg.546]    [Pg.111]    [Pg.276]    [Pg.70]    [Pg.129]    [Pg.346]    [Pg.346]    [Pg.111]    [Pg.276]    [Pg.83]    [Pg.74]    [Pg.260]    [Pg.501]    [Pg.1051]    [Pg.546]    [Pg.111]    [Pg.276]    [Pg.70]    [Pg.129]    [Pg.346]    [Pg.346]    [Pg.111]    [Pg.276]    [Pg.83]    [Pg.74]    [Pg.147]    [Pg.430]    [Pg.430]    [Pg.478]    [Pg.284]    [Pg.557]    [Pg.88]    [Pg.237]    [Pg.65]    [Pg.238]    [Pg.64]    [Pg.499]    [Pg.1180]    [Pg.1352]   
See also in sourсe #XX -- [ Pg.884 ]



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