- Method for preparing P-phenylenediamine
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The invention discloses a method for preparing high-purity p-phenylenediamine by reacting nitrobenzene with ammonia under the action of a catalyst to obtain 4-nitrosoaniline and 4-nitroaniline and then hydrogenating. Nitrobenzene and ammonia react under the action of a catalyst to generate 4-nitrosoaniline and 4-nitroaniline, the reaction selectivity is high, an ortho-position or meta-position product is not generated, and the yield is high. High-selectivity p-phenylenediamine can be obtained through catalytic hydrogenation of 4-nitrosoaniline and 4-nitroaniline, and the purity is high, so that the method is suitable for industrial production.
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Paragraph 0044-0068
(2021/01/24)
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- Tungstate-supported silica-coated magnetite nanoparticles: a novel magnetically recoverable nanocatalyst for green synthesis of nitroso arenes
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Tungstate ion was heterogenized on the silica-coated magnetite nanoparticles and applied for the selective oxidation of anilines to nitroso arenes—with hydrogen peroxide/urea as oxidant in dimethyl carbonate as solvent—in moderate–good yields (40–96%). The catalyst was characterized using different techniques including Fourier-transform infrared spectroscopy, X-ray powder diffraction, vibrating sample magnetometry, scanning electron microscopy, energy dispersive X-ray and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The catalyst was easily recovered using an external magnet and reused for six times.
- Jadidi Nejad, Masoume,Yazdani, Elahe,Kazemi Miraki, Maryam,Heydari, Akbar
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p. 1575 - 1583
(2019/09/09)
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- Synthesis of Di(hetero)arylamines from Nitrosoarenes and Boronic Acids: A General, Mild, and Transition-Metal-Free Coupling
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The synthesis of di(hetero)arylamines by a transition-metal-free cross-coupling between nitrosoarenes and boronic acids is reported. The procedure is experimentally simple, fast, mild, and scalable and has a wide functional group tolerance, including carbonyls, nitro, halogens, free OH and NH groups. It also permits the synthesis of sterically hindered compounds.
- Roscales, Silvia,Csák?, Aurelio G.
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supporting information
p. 1667 - 1671
(2018/03/23)
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- THE PREPARATION METHOD FOR 4-NITROSOANILINE
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The present invention refers to 4-manufacturing method relates to with child Neel phosphorus nitro, more particularly sodium urate (sodium urate), or their mixtures (potassium urate) potassium urate a urate in response to 40 to 120 °C nitrobenzene mono salt 4-nitro by the inclusion of step of manufacturing a nitrosoaniline, reactants use urate forming silicide film having excellent thermal stability the carbonate and ammonia and the like of a high yield conversion and without the formation of a leaving component 4-nitrosoaniline nitro method relates to manufacturing. (by machine translation)
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Paragraph 0062-0069
(2017/04/04)
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- An efficient preparation of 4-nitrosoaniline from the reaction of nitrobenzene with alkali metal ureates
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This paper describes the synthesis of alkali metal salts of urea (ureates) and their application to the direct preparation of 4-nitrosoaniline from nitrobenzene via nucleophilic aromatic substitution of hydrogen. Sodium and potassium ureates were readily prepared from the reaction of urea with sodium hydride, metal methoxides, and metal hydroxides. The effect of ureates as nucleophiles on the conversion of nitrobenzene to 4-nitrosoaniline was investigated and compared with that of a urea-metal hydroxide mixture. It was found that the ureates were superior for producing 4-nitrosoaniline owing to their higher thermal stability of the ureate. The ureate obtained from the treatment of urea with sodium hydride gave the highest yield for the preparation of 4-nitrosoaniline. The ureates generated from the reaction of urea with metal hydroxide also gave high yields of 4-nitrosoaniline. Catalytic hydrogenation of 4-nitrosoaniline afforded polymer-grade 1,4-benzenediamine in quantitative yield.
- Park, Jaebum,Kim, Hyung Jin
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p. 251 - 256
(2016/08/13)
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- THE PREPARATION METHOD FOR THE P-PHENYLENEDIAMINE
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The present invention relates to a method of preparing para-phenylenediamine, and more particularly, to a method of preparing para-phenylenediamine with excellent yield and excellent purity including: a first step of making sodium urate, potassium urate, or urate that is a mixture thereof react with mono-nitrobenzene at 40 to 120°C to prepare 4-nitrosoaniline; and a second step of performing a hydrogenation reaction of the prepared 4-nitrosoaniline to prepare para-phenylenediamine, wherein urate with excellent thermal stability is used as a reactant to prepare 4-nitrosoaniline with a high conversion rate and good yield without generating a by-product, such as carbonate, and ammonia.
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Paragraph 0072-0078; 0084-0086
(2017/04/19)
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- MANUFACTURING METHOD FOR 4-NITROSOANILINE FROM UREA AND NITROBENZENE
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A method for preparing 4-nitrosoaniline, including reacting urea and nitrobenzene in a polar organic solvent in the presence of a base at a temperature of room temperature to 150° C. The method uses a relatively cheap urea and nitrobenzene as the raw mate
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Page/Page column 5
(2008/06/13)
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- Manufacturing method for 4-nitrosoaniline from urea and nitrobenzene
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A method for preparing 4-nitrosoaniline, including reacting urea and nitrobenzene in a polar organic solvent in the presence of a base at a temperature of room temperature to 150° C. The method uses a relatively cheap urea and nitrobenzene as the raw mate
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- Trihalomethyl cations (CF3+, CF2Cl+ and CCl3+) as oxygen scavengers in gas phase
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Ion-molecule reactions of trihalomethyl cations generated from Freon-12 (CCl2F2), Freon-14 (CF4) and carbon tetrachloride studied in high pressure source of mass spectrometer show facile loss of oxygen atom from many nitro compounds.It has been shown by unmolecular dissociation in the field free region and by charge exchange spectra that the oxygen loss occurs through the formation of unstable adducts and during the collision process in a major pathway.
- Vairamani, M,Saraswathi, M
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p. 213 - 216
(2007/10/02)
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