Mono nitro phenol

The nitro derivatives of phenols are even more easily formed than the nitro derivatives of the hydrocarbons which, as will be recalled, are readily formed by the action of a mixture of nitric and sulphuric acids upon the hydrocarbon. Even with dilute nitric acid phenol undergoes substitution with the formation of a mono-nitro phenol and with concentrated acid a tri-nitro phenol results. 

Mono-nitro Phenols.—In the first reaction the product is a mixture of ortho-nitro phenol and para-nitro phenol. The two may be easily separated as the ortho compound is volatile with steam, crystallizing in beautiful yellow crystals, while the para compound is not volatile, being left behind when the mixture is distilled with steam. It is then extracted from the residue by boiling with hydrochloric acid, recrystallized from the same solvent and obtained as fine white needles. The preparation and separation of these two compounds is a very satisfactory laboratory exercise. The meta-nitro phenol can not be pre-... 

The NO 2 group is at the moment of solution fixed upon the phenol with the production of mono-nitro-phenol, which is afterwards reduced by the action of the zinc-dust into the amido derivative. During the subsequent combustion, the nitrogen of the amido-phenol becomes fixed in the state of ammonia. M. Chenel is perfectly satisfied with the results obtained, but he points out that the success of the operation depends upon the complete conversion of the phenol into the mono-nitro derivatives. This takes place whenever the organic compoimd forms a clear solution in the cold sulphuric acid mixture. Substances like collodion or gun-cotton must be very finely divided for successful treatment. The following table shows some of the results obtained by M. Chenel —... 

The simplest derivatives of this mixed character which yield dyes are the nitro naphthols, i.e., mixed nitro and hydroxyl substitution products. Recalling well-known compounds of the benzene series it will be remembered that whereas mono-nitro benzene has practically no color, and di-nitro-benzene only a faint yellow color, the mixed tri-nitro phenol or picric acid has an intense yellow color and was one of the first yellow dyes used. 

Nitro-phenolic compounds euid nitrous acid are similarly formed during the nitration of other aromatic hydrocarbons. Of those studied, the order from highest to lowest in proportion of by-products to mono-nitro product was - o-xylene, p-xylene, toluene, ethyl benzene, mesitylene, m-xylene, benzene. 

The long-known stimulating effect of mono- and polynitro com-pounds on the onset of fermentation in yeast maceration juice has been reinvestigated by Vandendriessche. The induction time is shortened significantly by 2,4- or 2,5-dinitrophenol, while 2,6-dinitro-phenol did not show such an effect. The influence is evident when using as substrates the fermentable hexoses and D-fructose-6-phosphate, but not hexose diphosphate. According to MarkoviCev a stimulation of the oxidation processes can be proved thereby. It is probable that these effects are related to the known phytochemical reduction of nitro compounds (see pp. 98 and 99). 

The nitro groups in 3,5-dinitrodiaryl ethers may be readily replaced with the residues of mono-and bis-phenols. The simplest 3,5-dinitrodiaryl ether - 3,5-dinitrodiphenyl ether - was reacted with 4-aminophenol or 4-acetamidophenol with the formation of 3-nitro-5-[4-amino(amido)]-phenoxydiphenyl ether subsequent transformation of this product led to 3-amino-5-(4-aminophenoxy)-diphenyl ether [24] (Scheme 4.9). 

With the simple aryl halides such as the mono-chlor derivatives of benzene or its homologues this reaction does not take place. Tf, however, a benzene halide has also substituted in the ring two nitro, sul-phonic acid or carboxyl groups, in the ortho and para positions to the halogen, then treatment of the halide with potassium hydroxide results in replacing the halogen with hydroxyl and the corresponding substituted phenol will be obtained. 

As both nitration and sulphonation take place with comparative ease, with either hydrocarbons or acids, and as the nitro compounds yield amino compounds and these yield diazo compounds, with their numerous reactions, in particular the Sandmeyer reaction for obtaining nitriles and as sulphonic acids are easily converted into phenols or nitriles it will be seen that by a combination of these synthetic reactions practically any desired ring-substituted mono-basic or poly-basic ring-carboxy acid may be obtained. 

Now when phthalophenone is hydrolyzed with alkalies it yields mono-carboxy tri-phenyl carbinol which on reduction yields mono-carbozy tri-phenyl methane and this by loss of carbon dioxide yields tri-phenyl methane. This means that phthalophenone is a lactone inner anhydride of mono-carboxy tri-phenyl carbinol and a true tri-phenyl methane derivative as shown in the reactions below. Now, also, phthalophenone by nitrating yields a di-nitro compound which by reduction yields a di-amino derivative and this by the diazo reaction has the two amino groups replaced by hydroxyls. The result is phenol phthalein, which is therefore also a lactone inner anhydride of mono-carboxy di-hydroxy tri-phenyl carbinol. All of these relationships may be represented by the following ... 

T. Urbanski and D browska [33b] examined infra-red spectra of several mono, di- and trinitrophenols and established the influence of the solvent on the hydrogen bond between the <7-nitro and phenolic groups. It was found that polar solvents can break the intramolecular hydrogen bond. 

The amido-sulphonic adds, since they are derivatives of a primary amine, may like them be diazotised by tile action of nitrous add upon tins fact depends their great technical importance. If the diazo-com-pounds thus obtained are combined with amines or phenols, azo dyes are formed which contain the sulphonic add group, and in the form of their alkali salts are soluble in water. Sulplianilic acid particularly, and its isomer, metanilic add, obtained by the reduction of m-nitro-benzenesulphonic add, as well as the numerous mono- and poly-sul-phonic acids derived from a and / naphthyl amines, find extensive technical application in the manufacture of azo dyes-... 

ANILINE, A -PHENYL (122-39-4) Comhustible solid. Dust forms explosive mixture with air. Violent reaction when added to hexachloromelamine, trichloromelamine. Often shipped in liquid form (flash point, liquid 307°F/153°C oc). An organic base. Incompatible with strong acids (forms salts), aldehydes, organic anhydrides, isocyanates, oxidizers. Reacts with nitrogen oxides to form Al-nitrosodiphenylamine and mono- and poly-nitro products. Incompatible with organic anhydrides, acrylates, alcohols, aldehydes, alkylene oxides, substituted allyls, cellulose nitrate, cresols, caprolactam solution, epichlorohydrin, ethylene dichloride, isocyanates, ketones, glycols, nitrates, phenols, vinyl acetate. Exothermic decomposition with maleic anhydride. Increases the explosive sensitivity of nitromethane. Attacks light metals in the presence of moisture. 

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