4- Nitrobenzene sulfonic acid

After absorption by the fiber, the leuco dye is converted to the original pigment by oxidation and, in this way, fixed to the fiber. Oxidation can be achieved with atmospheric oxygen or by the addition of oxidants, such as hydrogen peroxide, perborate, or 3-nitrobenzene sulfonic acid, to the liquor. 

C7H7N05S 4-methyl-3 nitrobenzene sulfonic acid 97-06-3 25 00 1.4712 2 10842 C7H8N402 theobromine 83-67-0 25.00 1.3600 2... 

Fluoro-3-nitrobenzene sulfonic acid, a reactant which has good solubility in water, is also of interest for derivatization of proteins ... 

Illustrate the layered accident investigation process, using Example 13-1 as a guide, to develop the underlying causes of the duct system explosion described in section 13-1. 13-2. Repeat Problem 13-1 for the bottle of isopropyl ether accident described in section 13-2. 13-3. Repeat Problem 13-1 for the nitrobenzene sulfonic acid decomposition accident described in section 13-2. 

Oxidation of dihydroquinacridone to quinacridone may be achieved, for instance, with the sodium salt of m-nitrobenzene sulfonic acid in aqueous ethanol in the presence of sodium hydroxide solution [7]. A distinction is made between heterogeneous and homogeneous oxidation. The reaction is referred to as a solid state oxidation if the solvent contains approximately 2% sodium hydroxide solution. A content of approximately 30% sodium hydroxide solution relative to the solvent mixture, on the other hand, converts the reaction into a so-called solution oxidation . The type of ring closure defines the crystal modification of the resulting dihydroquinacridone, while the oxidation technique defines the crystal phase of the quinacridone pigment. 

The crude pigment may also be treated with an aromatic sulfonic acid (such as toluene sulfonic acid, xylene sulfonic acids, m-nitrobenzene sulfonic acid) in sulfuric acid or with nitric acid at 80°C to yield a somewhat redder yellow transparent modification of flavanthrone [22],... 

Chloro-5-nitrobenzene sulfonic acid is synthesized by addition of p-chloro-nitrobenzene as a melt to 20% Oleum (20% S03 in H2S04) at 100 °C [1], This is added over 20 minutes to Oleum heated at 50 °C. The temperature then rises to 120-125 °C due to the heat of reaction. The conversion is achieved by maintaining this temperature during several hours with 2 bar of steam. 

Chemical Nature Sodium Salt of Meta Nitrobenzene Sulfonic Acid... 

AcOH, heat m-nitrobenzene sulfonic acid Na-salt... 

Derivation By the reduction of metal-nitrobenzene-sulfonic acid. Nitrobenzene is sulfonated until the product is soluble in water. The mixture is then poured into water and reduced with iron, made alkaline with lime, and the lime salt dissociated with sodium carbonate. 

Methyl p-Nitrobenzenesulfonate, p-Nitrobenzene-sulfonic acid methyl ester. C,HTNO,S mol wt 217.20. C 38.71%, H 3.25%, N 6.45%, O 36.83%, S 14.76%. Reagent for selective methylation or cysteine residues in chemical modification of proteins Nakagawa, Bender, J. dm. Chem. Sac, 91, 1566(1969). Procedure Heinrikson. Biochem. Bio-phys. Res. Common. 41, 967 (1970). Prepd by the general method of reacting p-nitrobenzenesulfony] chloride with alcohols. See Morgan, Cretcher, J. Am. Chem Soc. 70, 375 (1948). 

Amino-2-hydroxy-5-nitrobenzene sulfonic acid. See 6-Amino-4-nitro-1-phenol-2-sulfonic acid... 

Nitrobenzene is used mainly as an intermediate in the production of aniline. It also forms the basis for the production of 3-chloronitrobenzene, m-nitrobenzene-sulfonic acid and p-aminophenol its earlier importance in the production of the dyestuff intermediate benzidine is insignificant today, due to the carcinogenicity of the latter. The industrial production of nitrobenzene is achieved by isothermal nitration of benzene. Mixed nitration acid, composed of 40% HNO3, 40% H2SO4 and 20% water, is used as the nitrating medium. Whereas the process was originally carried out batchwise, continuous operation predominates today in plants with a capacity up to 100,000 tpa. Stainless steel equipment is used, which is resistant to corrosion due to a passivation effect. 

The Povarov reaction, an inverse electron-demand aza-Diels-Alder reaction of 2-azadienes with electron-rich olefins, allows a rapid construction of polysubstituted tetrahydroquinolines. It must be noted that enantiose-lective versions of the Povarov reaction remain rare. Actually, the first highly enantioselective example of this type of reaction was developed by Zhu et al., in 2009. Later, Jacobsen et al. reported another enantioselective Povarov reaction catalysed by a combination of a strong Bronsted acid, such as o-nitrobenzene sulfonic acid, with a chiral urea. As shown in Scheme 2.8, the reaction of electron-rich alkenes with imines provided the corresponding tricyclic products in good yields, moderate diastereoselectivities of up to 62% de, and generally high enantioselectivities ranging from 90 to 98% ee. 

Seheme 2.8 Povarov reaction catalysed by a combination of a chiral urea and o-nitrobenzene sulfonic acid. 

Nitro-1 -Naphthol (8-Nitro-l-oxy-naphthalene). (O2N)C10H6.OH,mw 189.18, N 7.41%, OB to C02 —173.38%, mp 212° (decompn). Prepn from 1-naphthy 1-m-nitrobenzene sulfonate by nitration with nitric acid in AcOH, then hydrolysis with piperidine... 

Certain derivatives of the lignin sulfonic acids can be determined directly in water. The nitroso derivatives, which are easily formed in solution, can be determined by differential pulse polarography [438]. Vanillin can be formed by alkaline hydrolysis [439] or alkaline nitrobenzene oxidation [440], extracted into an organic solvent and determined by gas chromatography. 

---