- Activated carbon supported bimetallic catalysts with combined catalytic effects for aromatic nitro compounds hydrogenation under mild conditions
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Non-noble nickel catalysts have been widely studied and tried in hydrogenation, however the problem of nickel particle sintering is more and more common in high-loaded nickel catalysts. A series of highly dispersed bimetallic Ni-M/AC (M = Cu, Co, Fe or Zn) catalysts were prepared by incipient wetness impregnation methods and applied in 1-nitronaphthalene hydrogenation to 1-naphthylamine under mild reaction conditions. The prepared catalysts were characterized by XRD, BET, H2-TPR, TEM, HRTEM, HAADF-STEM, XPS, ICP, FT-IR and H2 chemisorption. The results show that the introduction of the metal promoter inhibits the sintering of the nickel and enhances the reducibility of the catalysts, leading to higher ratio of effective Ni° on the surface of the support, especially for Ni-Zn/AC sample. Moreover, the results of XPS indicate that the electron donating effect of Cu promoter increases surface electronic density of Ni, as a result, the electron-rich Ni might be produced because of the interfacial electronic effect, which favors the desorption and further impedes the hydrogenation of N-naphthylhydroxylamine. Ni-Zn/AC-350 with smaller nickel particles, better dispersion and larger content of effective Ni° presents the best catalytic performance in 1-nitronaphthalene hydrogenation to 1-naphthylamine under mild reaction conditions, it gives 100% conversion of 1-nitronaphthalene and 96.82% selectivity to 1-naphthylamine under 0.6 MPa and 90℃ for 5 h. Additionally, superior performances are also obtained in hydrogenation reactions of nitrobenzene, chloronitrobenzene, 1,5-dinitronaphthalene and 1,8-dinitronaphthalene over Ni-Zn/AC catalysts. With good hydrogenation activity the catalyst shows, the application prospect in industrial production of aromatic amine from aromatic nitro compounds has been becoming more and more extension.
- Huang, Lei,Lv, Yang,Wu, Shengtao,Liu, Pingle,Xiong, Wei,Hao, Fang,Luo, He'an
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- Carbon networks based on 1,5-naphthalene units. Synthesis of 1,5-naphthalene nanostructures with extended π-conjugation
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The synthesis and spectroscopic characterization of nanometer-sized conjugated molecules of 5-X-naphthylethynyl (X= NO2, NMe2) units with precise length and constitution have been carried out. A new extended π-conjugated 5-nitronaphthyl family was synthesized by palladium-catalyzed cross-coupling reaction between the protected 5-iodonaphthylethynyl 5a and 1-ethynyl-5-nitronaphthalene 9, or the resulting ethynyl compound 11 and the 1-iodo-5-nitronaphthalene 3. Catalytic oxidative dimerization of the terminal acetylene compounds permits the isolation of the corresponding 1,3-butadiyne derivatives 16-18, with the nitro groups at the ends of the conjugation, in excellent yields. A new family of conjugated 5-nitro-(naphthylethynyl)-[5-(N,N-dimethylamino)]-naphthalene (20-22), was also synthesized by palladium-catalyzed cross-coupling reaction between 5-iodo-N,N-dimethylnaphthalene-1-amine (19) with the appropriate terminal acetylene (9, 11, and 13 respectively). Compounds 20-22 show a fluorescence emission and also exhibit a charge-transfer absorption in the visible spectrum. X-ray structure of 20 confirms a centrosymmetric dimer association with an interplanar distance of 3.43 A, and the naphthalene rings adopt an anti conformation around the C≡C triple bond.
- Rodriguez, J. Gonzalo,Tejedor, J. Luis
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- Synthesis of 1,5-naphthylethynyl nanostructure networks with extended π-conjugation. Effective heterocoupling catalyzed by palladium under a compatible CO2 atmosphere
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The synthesis of a new extended π-conjugated 5-N,N-dimethylaminonaphthyl family was undertaken by palladium-catalyzed cross-coupling reaction between a protected 5-iodonaphthylethynyl and 1-ethynyl-5-(N,N-dimethylamino)naphthalene. Under an argon atmosphere, only the homocoupling product 1,4-(N,N-dimethylamino)naphthyl-1,3-butadiyne was isolated, in excellent yield. However, under a compatible and pure carbon dioxide atmosphere, the cross-coupling product was obtained in excellent yield.
- Rodríguez, J. Gonzalo,Tejedor, J. Luis
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- Synthesis, structure and catalytic activity of the supported Ni catalysts for highly efficient one-step hydrogenation of 1,5-dinitronaphthalene to 1,5-diaminodecahydronaphthalene
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A series of the supported nickel catalysts have been synthesized through impregnation, characterized by X-ray diffraction, N2 sorption measurement, temperature programmed H2 reduction and X-ray photoelectron spectroscopy. The morphology and particle size of catalysts are imaged by scanning electron microscope. The catalysts have efficiently catalyzed the one-step hydrogenation of 1,5-dinitronaphthalene to 1,5-diaminodecahydronaphthalene. The catalyst 10%Ni/SiO2-1a is the most active for the titled hydrogenation with 100 mol% conversion and 95.3% selectivity, applicable for the catalytic one-step hydrogenation of nitro-aromatic compounds. The reducibility of NiO species on different supports has been carefully studied. Some factors such as the type of carriers, the addition of modifiers, the silica source, the Ni loading, the H2 pressure and the reaction temperature and time play important roles in controlling the hydrogenation. In addition, the negative effect of the water amount has been observed. The recycling tests reveal the recyclability and stability of the supported Ni catalyst.
- Lu,Wei,Zhou,Jiang,Sun,Xia
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- Half-Sandwich Ruthenium Complexes of Amide-Phosphine Based Ligands: H-Bonding Cavity Assisted Binding and Reduction of Nitro-substrates
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We present synthesis and characterization of two half-sandwich Ru(II) complexes supported with amide-phosphine based ligands. These complexes presented a pyridine-2,6-dicarboxamide based pincer cavity, decorated with hydrogen bonds, that participated in the binding of nitro-substrates closer to the Ru(II) centers, which is further supported with binding and docking studies. These ruthenium complexes functioned as the noteworthy catalysts for the borohydride mediated reduction of assorted nitro-substrates. Mechanistic studies not only confirmed the intermediacy of [Ru-H] in the reduction but also asserted the involvement of several organic intermediates during the course of the catalysis. A similar Ru(II) complex that lacked pyridine-2,6-dicarboxamide based pincer cavity substantiated its unique role both in the substrate binding and the subsequent catalysis.
- Pachisia, Sanya,Kishan, Ram,Yadav, Samanta,Gupta, Rajeev
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p. 2009 - 2022
(2021/02/06)
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- Efficient hydrogenation catalyst designing via preferential adsorption sites construction towards active copper
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Based on the experimental and DFT calculation results, here for the first time we built preferential adsorption sites for nitroarenes by modification of the supported Cu catalysts surface with 1,10-phenathroline (1,10-phen), by which the yield of aniline via reduction of nitroarene is enhanced three times. Moreover, a macromolecular layer was in-situ generated on supported Cu catalysts to form a stable macromolecule modified supported Cu catalyst, i.e., CuAlOx-M. By applying the CuAlOx-M, a wide variety of nitroarene substrates react smoothly to afford the desired products in up to > 99% yield with > 99% selectivity. The method tolerates a variety of functional groups, including halides, ketone, amide, and C = C bond moieties. The excellent catalytic performance of the CuAlOx-M can be attributed to that the 1,10-phen modification benefits the preferential adsorption of nitrobenzene and slightly weakens adsorption of aniline on the supported nano-Cu surface.
- Dai, Xingchao,He, Dongcheng,Li, Teng,Shi, Feng,Wang, Hongli,Wang, Tao,Wang, Xinzhi
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p. 397 - 406
(2021/07/21)
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- One-step catalytic amination of naphthalene to naphthylamine with exceptional yield
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One-step amination of aromatic compounds to arylamines is a promising strategy with high atom economy and less environmental pollution. We propose for the first time a direct catalytic amination of naphthalene to naphthylamine and hydroxylamine using vanadium catalysts under mild conditions. Naphthylamine was obtained in 70% yield over the V2O5/HZSM-5 cayalyst in a one-step amination of naphthalene, which is higher than the yield obtained by state-of-the-art processes. The Br?nsted acid sites, and the V-O-V and VO bonds of monovanadate in the V2O5/HZSM-5 catalyst are the active sites for the amination reaction and are responsible for the naphthalene activation and formation of NH3+ that acts as the active amination reagent. A possible reaction mechanism was also proposed by investigating real-time IR and in situ DRIFTS. This proposed one-step amination of naphthalene is superior to traditional nonselective nitration and hydrogenation processes, and some findings offer new insights to produce arylamines from aromatic compounds.
- Hao, Fang,Wang, Xin,Huang, Linfang,Xiong, Wei,Liu, Pingle,Luo, Hean
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supporting information
p. 2744 - 2749
(2020/06/17)
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- A capping agent dissolution method for the synthesis of metal nanosponges and their catalytic activity towards nitroarene reduction under mild conditions
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We report a general strategy for the synthesis of metal nanosponges (M = Ag, Au, Pt, Pd, and Cu) using a capping agent dissolution method where addition of water to the M@BNHx nanocomposite affords the metal nanosponges. The B-H bond of the BNHx polymer gets hydrolysed upon addition of water and produces hydrogen gas bubbles which act as dynamic templates leading to the formation of nanosponges. The rate of B-H bond hydrolysis has a direct impact on the final nanostructure of the materials. The metal nanosponges were characterized using powder XRD, electron microscopy, XPS, and BET surface area analyzer techniques. The porous structure of these nanosponges offers a large number of accessible surface sites for catalytic reactions. The catalytic activity of these metal nanosponges has been demonstrated for the reduction of 4-nitrophenol where palladium exhibits the highest catalytic activity (k = 0.314 min?1). The catalytic activity of palladium nanosponge was verified for the tandem dehydrogenation of ammonia borane and the hydrogenation of nitroarenes to arylamines in methanol at room temperature. The reduction of various substituted nitroarenes was proven to be functional group tolerant except for a few halogenated nitroarenes (X = Br and I) and >99% conversion was noted within 30-60 min with high turnover frequencies (TOF) at low catalyst loading (0.1 mol%). The catalyst could be easily separated out from the reaction mixture via centrifugation and was recyclable over several cycles, retaining its porous structure.
- Ghosh, Sourav,Jagirdar, Balaji R.
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p. 17401 - 17411
(2019/01/03)
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- METHOD FOR SPECIFIC CLEAVAGE OF C Alpha-C BOND AND SIDE CHAIN OF PROTEIN AND PEPTIDE, AND METHOD FOR DETERMINING AMINO ACID SEQUENCE
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The present invention provides a method for specifically cleaving a Cα-C bond of a peptide backbone and/or a side chain of a protein and a peptide, and a method for determining amino acid sequences of protein and peptide. A method for specifically cleaving a Cα-C bond of a peptide backbone and/or a side chain bond of a protein or a peptide, comprising irradiating a protein or a peptide with laser light in the presence of at least one hydroxynitrobenzoic acid selected from the group consisting of 3-hydroxy-2-nitrobenzoic acid, 4-hydroxy-3-nitrobenzoic acid, 5-hydroxy-2-nitrobenzoic acid, 3-hydroxy-5-nitrobenzoic acid, and 4-hydroxy-2-nitrobenzoic acid. A method for determining an amino acid sequence of a protein or a peptide, comprising irradiating a protein or a peptide with laser light in the presence of the above specific hydroxynitrobenzoic acid to specifically cleave a Cα-C bond of a peptide backbone and/or a side chain bond, and analyzing generated fragment ions by mass spectrometry.
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- Method for preparing diaminonaphthalene
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The invention provides a method for preparing diaminonaphthalene. The method comprises the following steps: carrying out a nitration reaction by adopting sulfuric acid, fuming nitric acid and naphthalene so as to obtain mixed dinitronaphthalene; adding a second organic solvent, the mixed dinitronaphthalene, a catalyst and activated carbon into a reaction kettle, raising the temperature to 60-65 DEG C, adding hydrazine hydrate, and reacting and separating so as to obtain second filtrate and second filter cake; separating and purifying the second filtrate so as to obtain a solid, namely 1,8-diaminonaphthalene; and separating and purifying the second filter cake so as to obtain 1,5-diaminonaphthalene. According to the preparation of the mixed dinitronaphthalene, the nitratlon reaction is carried out by adopting an organic solvent free method, the waste acid can be recycled, and the yield and treatment cost of the three wastes can be reduced. The mixed dinitronaphthalene is directly reduced, the separation cost is reduced, and the market competitiveness is improved for industrial production. By utilizing different physical properties of the mixed dinitronaphthalene in different organic solvents, 1,8-diaminonaphthalene and 1,5-diaminonaphthalene with high purity are separated.
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Paragraph 0042; 0043; 0049-0054; 0056-0061
(2017/08/29)
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- By the 1 - naphthylamine synthetic 1, 5 - diaminonaphthalene method two
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The invention discloses a method for synthesizing 1,5-diaminonaphthalene with 1-naphthylamine. The method is characterized in that in a mixed solvent of glacial acetic acid and water, 1-naphthylamine and hydroxylammonium salts carry out one-step reaction in the presence of catalysts, namely metavanadate and/or vanadium oxide, to generate 1,5-diaminonaphthalene. The method is low in cost, simple in process, short in flow and mild in reaction conditions, is environment-friendly and meets the industrial production requirements.
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Paragraph 0028; 0031; 0033; 0036; 0037-0038; 0040; 0042
(2017/11/23)
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- Structure-Activity and Structure-Property Relationship and Exploratory in Vivo Evaluation of the Nanomolar Keap1-Nrf2 Protein-Protein Interaction Inhibitor
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Directly disrupting the Keap1-Nrf2 protein-protein interaction (PPI) is an effective way to activate Nrf2. Using the potent Keap1-Nrf2 PPI inhibitor that was reported by our group, we conducted a preliminary investigation of the structure-activity and structure-property relationships of the ring systems to improve the drug-like properties. Compound 18e, which bore p-acetamido substituents on the side chain phenyl rings, was the best choice for balancing PPI inhibition activity, physicochemical properties, and cellular Nrf2 activity. Cell-based experiments with 18e showed that the Keap1-Nrf2 PPI inhibitor can activate Nrf2 and induce the expression of Nrf2 downstream proteins in an Nrf2-dependent manner. An exploratory in vivo experiment was carried out to further evaluate the anti-inflammatory effects of 18e in a LPS-challenged mouse model. The primary results indicated that 18e could reduce the level of circulating pro-inflammatory cytokines induced by LPS and relieve the inflammatory response. (Chemical Equation Presented).
- Jiang, Zheng-Yu,Xu, Li-Li,Lu, Meng-Chen,Chen, Zhi-Yun,Yuan, Zhen-Wei,Xu, Xiao-Li,Guo, Xiao-Ke,Zhang, Xiao-Jin,Sun, Hao-Peng,You, Qi-Dong
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supporting information
p. 6410 - 6421
(2015/09/08)
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- Functionalized Photoreactive Compounds
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The present invention concerns functionalized photoreactive compounds of formula (I), that are particularly useful in materials for the alignment of liquid crystals. Due to the adjunction of an electron withdrawing group to specific molecular systems bearing an unsaturation directly attached to two unsaturated ring systems, exceptionally high photosensitivities, excellent alignment properties as well as good mechanical robustness could be achieved in materials comprising said functionalized photoreactive compounds of the invention.
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- Process for producing 1,5-diaminonaphthalene
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The present invention relates to a process for producing 1,5-diaminonaphthalene without formation of 1,8-diaminonaphthalene and not through an unstable nitro imine and nitro enamine as intermediates, the process including the steps of dehydrogenating 5-substituted-1-tetralone to produce a naphthol compound and then aminating the hydroxyl group of the naphthol compound.
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- Process for the preparation of 5-nitro-3,4-dihydro-1(2H)-naphthalenone, 1,5-naphthalendiamine and 1,5-naphthalendiisocyanate
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A process for the production of 1,5-naphthalene diamine (I) comprises reaction of 4-(2-nitrophenyl)-n-butyronitrile to 4-(2-nitrophenyl)-n-butyric acid. Independent claims are included for: (1) a process for the production of 5-nitro-3,4-dihydro-1(2H)-naphthalinone by reaction of 4-(2-nitrophenyl)-n-butyronitrile to 4-(2-nitrophenyl)-n-butyric acid and; (2) a process for the production of 1,5-naphthalene diisocyanate by phosgenation of 1,5-naphthalene diamine (I).
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- peri-naphthalenediamines: XXXIV. 1,4,5,8-Tetrakis(dimethylamino)naphthalene: Alternative approaches to synthesis
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New methods were proposed for synthesizing 1,4,5,8-tetrakis(dimethylamino)naphthalene with an overall yield of 4 to 12% to replace the known procedure ensuring an overall yield of 2%. Catalytic hydrogenation was shown to be inapplicable for preparation of polyaminonaphthalenes from nitro compounds having 3 or 4 nitro gruops in the α-positions. Nucleophilic amination of 1,5-dinitronaphthalene in the system NH2OH/NaOH/MeOH yields 1-amino-4-nitronaphthalene. The nitration of 1,5-bis(p-tolylsulfonylamino)-naphthalene leads to formation of 2,6-dinitro rather than 4,8-dinitro derivative, as it was believed formerly. This was confirmed by transformation of the latter into 1,2,5,6-tetrakis(dimethylamino)naphthalene. 3-Nitro, 2,6-dinitro, 2,6-diamino, and 2,4,6,8-tetranitro derivatives of 1,5-bis(dimethylamino)naphthalene, nitro and amino derivatives of 1,4,5-tris(dimethylamino)naphthalene, and 4,5-diamino-1,8-bis(methylamino)naphthalene were synthesized. By treatment with perchloric acid 1,4,5,8-tetrakis(dimethylamino)naphthalene was oxidized to 2,3-dihydroperimidinium salt.
- Sorokin,Ozeryanskii,Pozharskii
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p. 699 - 708
(2007/10/03)
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- Process for the production of 1,5-naphthalenediamine
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The invention relates to a process for the production of 1,5-naphthalenediamine and to the intermediates 4-(2-nitrophenyl)butyronitrile, 5-nitro-3,4-dihydro-1(2H)-naphthyl-imine, 5-nitroso-1-naphthylamine, 5-nitro-1-naphthylamine, 4-(2-aminophenyl)-butyronitrile, 5-amino-3,4-dihydro-1(2H)-naphthalene imine, 4-(2-nitrophenyl)ethyl butyrate and 4-(2-nitrophenyl)butyramide obtainable during the process.
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- Hydrogenation of isomeric dinitronaphthalenes on a palladium-containing anion exchanger
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Liquid-phase hydrogenation of dinitronaphthalenes on the palladium-containing anion-exchange resin AV-17-8 (AV-17-8-Pd) and a Pd/C catalyst affords corresponding naphthylenediamines via the formation of nitronaphthylamines. The rate of the reaction depends on temperature, solvent nature, and the value of the effective charge on the oxygen atoms and the nitro group as a whole.
- Voronin,Mazurova,Klyuev
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- Synthesis of phthalonitrile resins containing ether and imide linkages
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Imide-containing phthalonitrile monomers are prepared from a phthalonitrile and an aromatic dianhydride. The monomer and a method for preparing the monomer is disclosed. These monomers are synthesized into heat resistant polymers and copolymers with aromatic ring structure incorporating imide and ether linkages. The synthesis of the high temperature thermosetting polymers and copolymers is also disclosed.
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- Process for the preparation of 1,5-dihydroxynaphthalene and 1,5-diaminonaphthalene
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The characteristic of the improved process for the preparation of 1,5-dihydroxynaphthalene and 1,5-diaminonaphthalene is to carry out the alkaline pressure hydrolysis of the disodium salt of naphthalene-1,5-disulphonic acid at temperatures from 270° to 290° C. and under 14 to 20 bar using an excess of sodium hydroxide solution such that the molar ratio NaOH/disodium salt of naphthalenesulphonic acid is at least 12:1. The 1,5-dihydroxynaphthalene which is obtained in this manner, without hazard and in substantially higher purity, is then aminated with ammonia in the presence of ammonium bisulphite to give 1,5-diaminonaphthalene, it being possible to achieve a further increase in the degree of purity of the 1,5-diaminonaphthalene by increasing the molar ratio NH3 /1,5-dihydroxynaphthalene to at least 6:1.
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- REDUCTION OF AROMATIC NITRO COMPOUNDS TO AMINES BY BENZENETELLUROL
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Benzenetellurol was conveniently generated by methanolysis of phenyl trimethylsilyl telluride or reduction of diphenyl ditelluride with phosphinic acid or sodium borohydride, and smoothly reduced aromatic nitro compounds to the corresponding amines.
- Ohira, Noriyuki,Aso, Yoshio,Otsubo, Tetsuo,Ogura, Fumio
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p. 853 - 854
(2007/10/02)
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- PARTIAL REDUCTION OF DINITROARENES TO NITROANILINES WITH HYDRAZINE HYDRATE.
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Dinitroarenes containing substituents such as hydroxyl and amine groups could be conveniently reduced with 3 molar equivalents of hydrazine hydrate in presence of Raney nickel catalyst in ethanol/1,2-dichloro-ethane solvent mixture to give a product wherein one of the two nitro groups was reduced to the amino group. The yields of the partial reduction products are good. Under similar conditions alkoxyl substitutes in the o,p-position to the nitro groups were displaced by the hydrazine to give 2,4-dinitrophenyl-hydrazine as the main product. The details of the reduction reaction are described.
- Avyyangar,Kalkote,Lugade,Nikrad,Sharma
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p. 3159 - 3164
(2007/10/02)
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- Process for the monoacylation of an aromatic primary diamine
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A process for the monoacylating of an aromatic primary diamine containing no anionic water-solubilizing group, preferably m-phenylene or p-phenylenediamine, which comprises reacting an acylating agent in aqueous medium with a mineral acid salt, preferably the hydrochloric acid salt, of the diamine wherein the reaction mixture is maintained at a pH of from 1.5 to 3.5 during the addition and reaction of the acylating agent.
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- Manufacture of aromatic amino compounds
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A process for producing an aromatic amine comprises heating an aromatic sulfonate and a metal amide in liquid ammonia in a closed reactor at a temperature of at least 40° C to produce a metal arylamide and reacting the resultant metal arylamide with water or lower aliphatic alcohol to produce an aromatic amine.
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- Process for manufacturing diaminonaphthalene
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Diamino naphthalene having the formula STR1 wherein R1 is hydrogen or amino is prepared by treating dinitro naphthalene having the formula STR2 wherein R2 is hydrogen or nitro WITH HYDROGEN IN THE PRESENCE OF HYDROGENATION CATALYSTS AND ORGANIC SOLVENTS HAVING THE FORMULA STR3 wherein R3 is hydrogen, halogen or alkyl; R4 is hydrogen, halogen, alkyl, hydroxy, alkoxy, amino, alkylamino, or dialkyl amino; R5 is hydrogen, chlorine, alkyl, hydroxy, alkoxy, amino, alkylamino or dialkyl amino; R6 and R7 are the same or different and are either hydrogen or alkyl or together form a --(CH2)4 group, optionally substituted once or several times by methyl and/ethyl.
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