Nitrosodiphenylamine, substituted

The result of preventive measures is shown in Table VIII. In a tire and tube factory nitrosodiphenylamine (NDPhA) was substituted by cyclohexylthiophthalimid (PVI) to remove the major nitrosating agent. 

Amination of aromatic nitro compounds is a very important process in both industry and laboratory. A simple synthesis of 4-aminodiphenyl amine (4-ADPA) has been achieved by utilizing a nucleophilic aromatic substitution. 4-ADPA is a key intermediate in the rubber chemical family of antioxidants. By means of a nucleophibc attack of the anilide anion on a nitrobenzene, a o-complex is formed first, which is then converted into 4-nitrosodiphenylamine and 4-nitrodiphenylamine by intra- and intermolecular oxidation. Catalytic hydrogenation finally affords 4-ADPA. Azobenzene, which is formed as a by-product, can be hydrogenated to aniline and thus recycled into the process. Switching this new atom-economy route allows for a dramatic reduction of chemical waste (Scheme 9.9).73 The United States Environmental Protection Agency gave the Green Chemistry Award for this process in 1998.74... 

Other more complex examples are known,156-167 of which some are tranquillizing, antiasthmatic, or analgesic.I56,I57J6S The parent triazolo-[4,5-b]pyridine 4 has also been made from 1,2-diaminopyridine with N-nitrosodiphenylamine.168 If N-substituted diaminopyridines are used, N-sub-stituted triazolopyridines can be obtained.I53,169 l8° Examples are provided by... 

Unsymmetrical disubstituted hydrazines (1,1-diphenylhydrazine and 1,1-dimethylhydrazine) do not exhibit a detectable reaction with O2"- in the gas phase nor in Me2SO within approximately 10 min. This is consistent with the hypothesis that only those substituted hydrazines with a secondary amine function react with O2 - by hydrogen-atom transfer. Although there is a report that 1,1-diphenylhydrazine reacts with superoxide ion to produce N-nitrosodiphenylamine, such a product is more consistent with a peroxide reaction (a likely possibility for the reaction conditions). 

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. 

Condensation of 2-nitrosodiphenylamines with a variety of highly stabilized carbanions of dialkyl malonates, alkyl phenylacetates, and trialkyl phosphonoacetates is an efficient way for the synthesis of a great deal of substituted iV-arylquinoxalin-2 (l//)-ones (Scheme 101) [235, 236]. Double additions of anions of 2-cyanoalkyl carboxylates to 2-nitroso-4-alkylaminodiphenylamines result in the formation of pyrroloquinoxaUnones [236]. 

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