Naphthol yellow

This leaction is lesorted to for the reason that naphthalene forms only the n-nitro-compound with niti icacid. The method, similar to that used for prepaiing aniline from nitiobenzene, cannot, therefore, be employed for the production of /3-n.tphtliyl-.amine. u-Naphthol is mainly used foi the manufacture of yellow and orange colours (Martins and naphthol yellow) by the action of nitric acid, and are similai m constitution to picric acid (see Prep. 107). 

Naphthalene, 216 Naphthalene picrate, 217 Naphthalene sulphonaie ofsodiiim, 218-/ J-Naphthol, 219 Naphthol yellow, 224 /i Naphthyl acetate, 222 /j-Naphthyl methyl ether, 220 /-Nitracetanilide, 153 w-Nitraniline, 154 /-Nitraniline, 153 Nitric acid (fuming), 22 NitroVienzene, 142 w-Nitrobenzoic acid, 200 Nitrogen, qualitative e rimation, 2 quantitative estimation, 13 Nitrophenol, 183 Nitrosohenzene, 146 /-Nitrosodimethylaniline, 157 Niirosoplienol, 159... 

Naf tol, n. naphthol. -artikel, m. (Dyeing) naphthol style, -at, n. naphtholate. -blsu, n. naphthol blue, -gelb, n. naphthol yellow, -griin, n. naphthol green. 

Orange 1 - 4-Phenylazo)-2-naphthol Yellow N,N-Dimethyl-p-phenylazoaniline Blue 1,4-Diamylaminoanthraquinone Mixts of these dyes produce muddy colors of various hues... 

Chitosan-clay bio-nanocomposites showing the ability to incorporate anionic species can be used to prepare functionalized biohybrids. An example is the uptake of anionic dyes such as fast green and naphthol yellow S which are low-toxicity... 

The hydroxy-nitro dye Naphthol Yellow S (6.233 Cl Acid Yellow 1) was discovered in 1879 by Caro and is still manufactured. It is produced by sulphonation of 1-naphthol to give l-naphthol-2,4,7-trisulphonic acid, followed by replacement of the 2- and 4-sulpho groups in nitric acid medium. Nucleophilic substitution of l-chloro-2,4-dinitrobenzene with 4-aminodiphenylamine-2-sulphonic acid gives Cl Acid Orange 3 (6.234). 

A few Naphthol Yellow pigments which are coupling components of the acetoacetic arylide series are also considered members of the Naphthol AS series (see footnote to Table 10, p. 191). These are internationally known as Naphtol AS-G , Naphtol AS-IRG , etc. Naphtol AS-IRG, for instance, is acetoacetic-2,5-methoxy-4-chloroanilide (see also Table 10). 

DINITRO-a.NAPHTHOL-7-SULPHONIC ACID 1 (Naphthol Yellow S)... 

Naphthol yellow S, called by A. Kossel flavianic acid , is used in the isolation of arginine (p. 404). 

Fig. 9A,B. Space-filling models optimized conformationally A for 8 B for a complex of 8 with Naphthol Yellow S. Two macrocyclic rings of the host are removed for simplicity to show coiiformational change in the binding moieties of 8 (Taken from [44])...

Naphthol Yellow S (citronin A, flavianic acid sodium salt, 8-hydroxy-5,7-dinitro-2-naphthalene sulphonic acid disodium salt) [846-70-8] M 358.2, dec on heating. Greenish yellow powder soluble in H2O. The free sulphonic acid can be recrystd from dil HCl (m 150°) or AcOH-EtOAc (m 148-149.5°). The disodium salt is then obtained by dissolving the acid in two equivalentss of aqueous NaOH and evaporating to dryness and drying the residue in a vacuum desiccator. The sodium salt can be recrystd from the minimum volume of H2O or from EtOH [Dermer and Dermer JACS 61 3302 1939]. 

The free dinitronaphtholsulfonic acid can be prepared readily from commercial Naphthol Yellow S by treating a filtered saturated solution of the dye with three volumes of concentrated hydrochloric acid. The crystals which separate are washed with cold 20 per cent hydrochloric acid and dried, first in air and finally in a vacuum desiccator over solid sodium hydroxide. 

Preparation 392.—Naphthol Yellow S. (2 i-Dinitro-l-naphthd-1-sulphonic add) (K Salt). 

Picric acid and Naphthol Yellow S may be estimated in a similar manner. 

Noteworthy among the yellow lakes are those of yellow wood, quercitron, Persian berries, naphthol yellow, auramine, thioflavine, chrysoidine, quinoline yellow, met anil yellow and its analogues. 

Naphthol yellow S, Martius yellow, naphthylamme yellow, naphthalene yellow, citronine A, etc. Solution Ibecomcs colourless or very pale yellow. 

Erythrosine Extra Fuchsin S Guinea Green B Hessian Purple NR Columbian Black Naphthol Yellow S Nyanza Black Orange II Patent Blue A Picric Acid Ponceau 4GB Primuline Resorcin Yellow Rose Indulin 2G Acid Violet 5BN Acid Violet 6B Salm Red Tartrazin... 

Dinitro-l-naphthol-7-sulfonic acid (naphthol yellow S)... 

Naphthol yellow S, 151 Naphthsultone, 187, 217 a-Naphthylamine, 176 diazotization, 245, 260 technical observations, 178 y3-Naphthylamine, 54, 203 diazotization, 246 Naphthylamine black D, 277 l-Naphthylamine-2,4-disulfonic add, 80, 85, 178... 

Similar methods are used for preparing Martins yellow (2,4-dinitro-1-naphthol) and naphthol yellow S (l,2-dinitro-4-naphthol-7-sulfonic acid), as well as dinitrocresol and other polynitro compounds. If the concentration of the mixed acid is sufficiently high, the reaction succeeds with nearly the theoretical amount of nitric acid. 

FRENCH) GOLDEN YELLOW MANCHESTER YELLOW MARITUS YELLOW NAPHTHOL YELLOW NAPHTHYLENE YELLOW SAFFRON YELLOW ZLUT MARCIOVA ZLUT NAFTOLOVA... 

NAPHTHOL N--METHYLCARBAMATE see CBM750 NAPHTHOL YELLOW see DUX800... 

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