156-10-5Relevant articles and documents
Synthesis method of 4-nitrosodiphenylamine
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Paragraph 0009; 0010, (2021/04/26)
The invention relates to a synthesis method of p-nitrosodiphenylamine, in particular to a new process for preparing p-nitrosodiphenylamine by reacting N-carbanilide with nitrobenzene in the presence of proper alkali and a solvent. According to the invention, N-carbanilide with excellent reactivity and selectivity is adopted to react with nitrobenzene, and cheap alkali metal, alkaline earth metal and a polar organic solvent are adopted. And the method has the advantages of simple process, no by-product, high yield, no corrosive wastewater and environmental pollution reduction. And no chlorine-containing wastewater is generated, so that factors for corroding equipment can be eliminated.
Preparation method of 4-nitrodiphenylamine and 4-nitrosodiphenylamine
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Paragraph 0049-0090, (2019/02/04)
The invention provides a preparation method of 4-nitrodiphenylamine and 4-nitrosodiphenylamine. The preparation method comprises the following steps: (1) dissolving anhydride and/or aromatic dibasic acid as well as aniline into an organic solvent and performing ammonolysis or acylation reaction; and (2) adding nitrobenzene and a catalyst into the solution obtained in the step (1) and performing condensation reaction to generate the 4-nitrodiphenylamine and the 4-nitrosodiphenylamine. A reaction product of the aniline and the anhydride and/or the aromatic dibasic acid is used for replacing theaniline to react with the nitrobenzene, so on one hand, the steric hindrance of the reaction product and nitrobenzene ortho-reaction is increased and generation of ortho-reaction byproducts is effectively inhibited; and on the other hand, the protective effect on amino is achieved and the side reaction that two molecule aniline are condense to generate azobenzene is avoided, so that the yield of the target product is increased and energy consumption in the separation and purification link is reduced. Furthermore, the cost of the raw materials such as the anhydride and the aromatic dibasic acidis low, and the method is suitable for industrialized production.
Preparation of N-phenyl-p-phenylenediamine by coupling of aniline and nitrobenzene in KOH–poly(ethylene glycol) medium
Babkin, Alexander V.,Asachenko, Andrey F.,Uborsky, Dmitry V.,Kononovich, Dmitry S.,Izmer, Vyatcheslav V.,Kudakina, Vera A.,Shnaider, Viktoriya A.,Shevchenko, Nikolay E.,Voskoboynikov, Alexander Z.
, p. 555 - 557 (2016/11/29)
A novel protocol for efficient coupling of nitrobenzene and aniline in poly(ethylene glycol) medium in the presence of KOH giving diphenylamine derivatives has been developed, to enable the exclusion of the toxic tetramethylammonium hydroxide catalyst commonly used in the rubber antidegradant industry.
A 4-aminodiphenylamine catalytic hydrogenation of the apparatus and process for the production of
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Paragraph 0035-0036, (2017/03/22)
The invention relates to a device and process for producing 4-aminodiphenylamine by catalytic hydrogenation. The 4-aminodiphenylamine is prepared from materials by catalytic hydrogenation in a continuous production device consisting of a highly efficient tubular reactor and corresponding equipment without participation of a solvent under a fully closed state via reasonable process steps in the presence of a relatively inexpensive and easily available Raney nickel catalyst by selecting a highly efficient gas, liquid, solid catalytic hydrogenation tubular reactor. According to the device and process disclosed by the invention, the consumption of the Raney nickel catalyst is less than 0.1%, the conversion rate can reach 100%, the selectivity is 99.5% or more and the yield is above 99.8%.
PROCESS FOR THE PREPARATION OF 4-AMINODIPHENYLAMINE PRECURSORS
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Page/Page column 5, (2015/07/07)
Process for the preparation of 4-aminodiphenylamine precursors by reacting aniline and nitrobenzene in the presence of water and a base, with controlled amount of water with respect to the base, characterised in that the mole ratio of water to the dosed base, obtained after extraction of organic impurities by an aromatic solvent of an aqueous phase from hydrogenation of a condensation mixture, is between 3.99 and 3:1 at the start of the coupling reaction, and between 0.40 and 0.59:1 at the end of the coupling reaction, and the end of the coupling reaction is indicated by full conversion of nitrobenzene or by achieving the maximum content 2 wt. % of the initial amount of nitrobenzene in the reaction mixture. The ingredients are continuously fed into reactor cascades in the required ratio to the condensation process, the mole ratio of aniline to nitrobenzene is between 1 :1 and 10:1, and hydrogenation of the condensation product in the presence of a hydrogenation catalyst and added water is followed by separation of the hydrogenation catalyst, and an organic phase, containing 4-aminodiphenylamine, is separated from the aqueous phase, containing the released base.
IMPROVED PROCESS FOR PREPARING 4-AMINODIPHENYLAMINE
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Page/Page column 19; 20, (2013/09/26)
A process for preparing 4-aminodiphenylamine (4-ADPA) comprising steps of coupling of aniline with nitrobenzene in presence of a suitable base, e.g. tetramethylammonium hydroxide (TMAH), hydrogenation of the coupling mass, phase separation, hydrogenation of azobenzene in the separated organic mass and fractional distillation for 4-ADPA recovery. An improvement in 4-ADPA recovery and a lowering of tar formation are obtained due to azobenzene reduction prior to 4-ADPA isolation. Also a gain in volume productivity of 4-ADPA is obtained by suitably altering the batch cycle time of the coupling reaction.
AN EFFICIENT CONTINUOUS PROCESS FOR MANUFACTURING OF 4-AMINODIPHENYLAMINE FROM ANILINE AND NITROBENZENE
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Page/Page column 28-29, (2013/11/05)
An efficient continuous manufacturing process for 4-aminodiphenylamine by coupling aniline with nitrobenzene in the presence of tetramethylammonium hydroxide (TMAH) as a base, using flow reactors wherein base decomposition is considerably reduced by optimizing base quantity, process conditions and process equipment. Accordingly, in brief summary, one embodiment of the present invention is a process which comprises one or more of the steps of reacting aniline and nitrobenzene in the presence of water and TMAH as a base, in a continuous manner by feeding the reactants to a series of continuous flow reactors, while continuously distilling off an aniline-water mixture under, reduced pressure such that the water to total base molar ratio is less than 0.6:1 at the flow reactors outlet, and the water to unbound TMAH molar ratio is about 4: 1 in the reaction product.
METHOD FOR PREPARING 4-AMINODIPHENYLAMINE
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Page/Page column 8-9, (2008/06/13)
The present invention relates to a method for preparing 4-aminodiphenylamine comprising the steps of reacting carbanilide and nitrobenzene in an adequate solvent in the presence of an appropriate organic base or a mixture of an organic base and an inorganic base and subsequently reducing the reaction product, or a 4-aminodiphenylamine intermediate, without separation from the reaction mixture, in the presence of an appropriate catalyst and hydrogen gas. Because the method of the present invention uses carbanilide as starting material, which reacts directly with nitrobenzene with high reactivity and selectivity, generation of by-products such as phenazine and 2-nitrodiphenylamine can be reduced and the 4-aminodiphenylamine intermediate can be prepared with good selectivity and production yield. Also, because a recyclable organic base is used, amount of wasted material can be minimized and 4-aminodiphenylamine, or the final product, can be prepared efficiently, without the separation of 4-aminodiphenylamine intermediate for the subsequent reduction process. In addition, in comparison with conventional preparation methods of 4-aminodiphenylamine, generation of harmful wastes can be significantly reduced and environment-damaging corrosive materials are not generated.
METHOD FOR PREPARING 4-AMINODIPHENYLAMINE
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Page/Page column 5, (2008/06/13)
4-aminodiphenylamine is prepared by reacting carbanilide and nitrobenzene in an adequate solvent, which may be nitrobenzene, in the presence of an appropriate organic base, which may be tetramethylammonium hydroxide, alone or in mixture with an inorganic base and subsequently reducing the reaction product in the presence of an appropriate catalyst and hydrogen gas. The subsequent reduction may be carried out on the reaction mixture before the reaction mixture is subjected to separation.
Process for preparing 4-aminodiphenylamine
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Page/Page column 9-10, (2008/06/13)
The present invention discloses a process for preparing 4-aminodiphenylamine, which process uses nitrobenzene and aniline as raw materials, a complex base catalyst as condensation catalyst and a powdery composite catalyst as hydrogenation catalyst, and comprises five process stages: condensation; separation I; hydrogenation; separation II; and refining. The process can be continuously carried out. By selecting a complex base catalyst to catalyze the condensation reaction and separating it prior to the hydrogenation, the problem that the complex base catalysts thermally decompose in the hydrogenation reaction is avoided, the selectable range of hydrogenation catalysts is largely enlarged so that it is possible to select cheaper hydrogenation catalyst, and the selection of production process and equipment is easier and further industrialization is easier. The complex base catalysts used in the present invention are inexpensive and have higher catalytic activity. The process can be carried out at mild conditions and can adapt to broad range of water content, by-product is less and conversion and selectivity are higher. The operational strength is low, no corrosive liquid is produced, and environment pollution is reduced. The purity of 4-aminodiphenylamine prepared can exceed 99 wt.-%, and the yield in the industrial production process can be over 95%.
