Green, Acid Naphthol

Colour Tests. Antimony Pentachloride—green- brown Naphthol-Sulphuric Acid—green-brown/orange-brown Sulphuric Acid—pink-orange. 

Colour Tests. Antimony Pentachloride—green-yellow Naphthol-Sulphuric Acid—red-brown/red-brown Sulphuric Acid— orange-yellow. 

Green B, naphthol n. Iron lake of 1-nitroso-2-naphthol-3-carboxylic acid. 

The only nitroso dyes important commercially are the iron complexes of sulfonated l-nitroso-2-naphthol, eg. Cl Acid Green 1 [57813-94-2] (78) (Cl 10020) these inexpensive colorants are used mainly for coloring paper. 

Fe7-ric chloride reaclion.—Dissolve a drop of the free phenol in water and add a drop of ueutral ferric chloride. A green (catechol), blue (orcinol, pyiogallol) or purple (phenol, resorcinol) colouration is produced, which is often destroyed by acid or alkali. Quinol is o.xidised to quinone, and turns biown (p. 193). The naphthols give precipitates of dinaphthol (p. 220). 

Dissolve 0.3 g of miconazole nitrate in 50 mL of a mixture of 1 volume of glacial acetic acid R and 7 volumes of methyl ethyl ketone R. Using 0.2 mL of naphthol-benzein solution R as indicator, titrate with 0.1 M perchloric acid until the color changes from orange-yellow to green. One milliliter of 0.1 M perchloric acid is equivalent to 41.61 mg of C18H14CI4N2O. 

Condensation of a diphenylmethanol derivative, such as Michler s hydrol (6.159), with a reactive aryl component under acid conditions (the hydrol synthesis) also provides a leuco base. The dye 6.163 (Cl Acid Green 50) is made by reacting Michler s hydrol with R acid (2-naphthol-3,6-disulphonic acid) and oxidising the resulting leuco compound (Scheme 6.30). 

Using 2NpOH and 2-naphthol-3,6-disulfonate [121] as excited-state proton emitters, a transient high proton concentration is achieved on the membrane surface. With bromocresol green dye adsorbed on the membrane serving as a pH indicator, it has been found that the protons first react with the acidic ionized moieties on the surface and then reach the strongest base on the surface by rapid exchange. 

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... 

Colour Tests. Naphthol-Sulphuric Acid—green/brown-yellow Sulphuric Acid—orange (slow). 

Colour Tests. Naphthol-Sulphuric Acid—orange-brown/ orange Sulphuric Acid—yellow (green fluorescence under ultraviolet light). 

Colour Tests. Antimony Pentachloride—orange Naphthol-Sulphuric Acid—orange-red/blue-black Sulphuric Acid—yellow (green-yellow fluorescence under ultraviolet light). Thin-layer Chromatography. Deoxycortone acetate system TP Rf 86 system TQ—Rf 52 system TR—Rf 98 system TS—Rf 95. DPSTsolution.)... 

Colour Tests. Antimony Pentachloride—green Naphthol-Sulphuric Acid—yellow-green/yellow Sulphuric Acid—orange-pink. 

Colour Tests. Antimony Pentachloride—brown Naphthol-Sulphuric Acid—red-brown/brown-green Sulphuric Acid— orange-red. 

Colour Tests. Antimony Pentachloride—orange Naphthol-Sulphuric Acid—orange-red Sulphuric Acid—orange (green-yellow fluorescence under ultraviolet light). 

Shaterian and co-workers [180] have described an efficient and expeditious route towards the synthesis of l-amidoalkyl-2-naphthols 127 via a three-component reaction of an aryl aldehyde, 2-naphthol and acetamide in the presence of Fe(HS04)3 using a domestic microwave oven. The reaction of 2-naphthol with an aromatic aldehyde in the presence of an acid catalyst gives an o-quinone methide that is subsequently reacted with acetamide to give the desired product 127. This solvent-free microwave-assisted green procedure offers the advantages of short... 

Dinitro-8-acetoxy-naphthol-(l), acetic acid-[2,7-dinitro-8-hydroxy-naphthyKl)-ester], [2,7-dinitro-8-hydroxy-naphthyl- 1)] -acetate). HO.(02N)2C,oH4.0COCH3, mw 292.22, N 9.59%, OB to CO2 —149.81%, gold-green crysts from AcOH, mp 125-70° (decompn). Prepn from 2,7 ( )-dinitro-naphthalendiol-(l, 8) by reaction with AC2O for one hour at RT Ref BeU 6, 5285 ... 

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