3.4- Dichloro-6-aminophenol

Conversion to soluble salts in alkaline media on boiling in alkaline solutions hydrolysis to 3,4-dichloro-6-aminophenol... 

Uses. (9-Nitrochlorobenzene is used in the synthesis of azo dye intermediates such as o-chloroaniline (Fast YeUow G Base), i9-nitroani1ine (Fast Orange GR Base), o-anisidine (Fast Red BB Base), o-phenetidine, and (9-aminophenol (see Azo dyes). It also is used in corrosion inhibitors, pigments, and agriculture chemicals. -Nitrochlorobenzene is used principally in the production of intermediates for azo and sulfur dyes. Other uses include pharmaceuticals (qv), photochemicals, mbber chemicals (qv), and insecticides (see Insectcontroltechnology). Typical intermediates manufactured from the para isomer are -lutioaruline (Fast Red GC Base), anisidine, -aminophenol, -nitrophenol, -phenylenediamine, 2-chloro-/)-anisidine (Fast Red R Base), 2,4-dinitrochlorobenzene, and l,2-dichloro-4-nitrobenzene. 

Acid YeUow 23 (31), commonly known as Tartraziae, stiU maintains sales of nearly 0.5 million /yr ia the United States. It was first discovered ia 1884 and is made by coupling equimolar quantities of diazotized sulfarulic acid to 3-carboxy-l- -sulfophenyl)-5-pyrazolone. Other monoazopyrazolone dyes of commercial importance iaclude Acid YeUow 17 (32) (sulfarulic acid — l-(2,5-dichloro-4-sulfophenyl)-3-methyl-5-pyrazolone and Acid YeUow 40 [6372-96-9] (33) (Cl 18950) (p-aminophenol l-(4-chloro-2-sulfophenyl)-3-methyl-5-pyrazolone) foUowed by esterification of the phenoUc hydroxy group with -toluenesulfonyl chloride. 

The potassium chlorate both oxidises and chlorinates. If chromic acid, or even weaker oxidising agents, is employed the dichloro-quinone is obtained. The oxidation of aminophenols is illustrated in the following, in which nitrous acid serves as oxidising agent. 

HC—C( NC1)—CH mw 210-46 yel ndls (from ale), mp 67-68° was prepd from the HCl salt of 2,6-dichlofo-4 aminophenol by treating it with an acidic chloride of lime soln (Ref 1) It is reported by B.T. Taranto of Schering Cotp, Bloomfield, NJ (Ref 2) that this reagent, used for spot visualization in chromatographic systems, presents a potential expln hazard. Tests of this compd and of the 2,6-Dihromo deriv (qv) in a thermal stability bomb showed both to be expl, but the dichloro deriv was not as unstable as the dibromo deriv Refs 1) Beil 7, 634 2) Anon, C EN 45,... 

Dichlorophenol has been prepared by the chlorination of phenol with chlorine gas in the presence of nitrobenzene and fuming sulfuric acid, by the decomposition of the diazotate of 2,6 dichloro-4-aminophenol, eind by the decarboxylation of 3,5-dichloro-4-hydroxybenzoic acid in quinoline or dimethyl-aniline. ... 

Recently, bis-sulfonamido-crowns have been prepared from 5-nitro-2-ami-nophenol without the need to protect the amine group in the first step. The aminophenol was reacted with l,8-dichloro-3,6-dioxaoctane in DMF in the presence of potassium carbonate to form the intermediate diamine (method Z-24) (Dziomko et al., 1989). Here, the phenoxide rather than the amine... 

Dichloro-6-aminophenol 4,6-Dichloro-o-aminophenol. See 2-Amino-4,6-dichlorophenol... 

Dichloro-2-benzothiazolamine 2,6-Dichloro-p-phenylenediamine Diethylacetic acid Diethylamine N,N-Diethyl-m-aminophenol... 

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