87-63-8Relevant articles and documents
Single-atom Fe-N4site for the hydrogenation of nitrobenzene: theoretical and experimental studies
Dong, Panpan,He, Rong,Liu, Yan,Lu, Ning,Mao, Junjie,Wu, Konglin,Zhang, Wenzhuang,Zheng, Yamin
supporting information, p. 7995 - 8001 (2021/06/21)
The hydrogenation of nitrobenzene to aniline is an important process in the industry of fine chemicals, but developing inexpensive catalysts with expected activity and selectivity still remains a challenge. By using density functional theory calculations, we demonstrated that the isolated Fe atom not only can weaken the adsorption of reactants and reaction intermediates as compared to Fe nanoparticles, but also remarkably decrease the reaction barrier for the hydrogenation of nitrobenzene to aniline. Thus, the Fe single-atom (Fe SA) catalyst is considered as an ideal catalyst for this reaction. This theoretical prediction has been subsequently confirmed by experimental results obtained for the Fe SAs loaded on N-doped hollow carbon spheres (Fe SAs/NHCSs) which achieved a conversion of 99% with a selectivity of 99% for the hydrogenation of nitrobenzene. The results significantly outperformed the Fe nanoparticles for this reaction. This work provides theoretical insight for the rational design of new catalytic systems with excellent catalytic properties.
Synthesis method of key raw material 2-chloro-6-methylaniline of dasatinib
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, (2021/04/21)
The invention discloses a synthetic method of a key raw material 2-chloro-6-methylaniline of dasatinib. The method comprises the following steps: firstly, protecting a 1-site amino group of 2-nitro-6-methylaniline, then reducing a 2-site nitro group of 2-nitro-6-methylaniline into an amino group, then carrying out diazotization reaction, carrying out chlorine substitution on the 2-site amino group by using cuprous chloride, and finally, carrying out acidolysis to remove a 1-site amino protecting group to obtain 2-chlorine-6-methylaniline. The method has the advantages of cheap and easily available raw materials, easily controllable reaction, simple operation steps, simple post-treatment, recyclable solvents, small pollution, and suitableness for large-scale production of generative enterprises.
Preparation method of 2-chloro-6-methylaniline
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Paragraph 0030-0040, (2021/02/13)
The invention discloses a preparation method of 2-chloro-6-methylaniline. The method comprises the following steps: by using 3-chloro-5-methyl-4-nitroaniline as a starting raw material, water as a solvent and sulfuric acid as a reactant, carrying out diazotization reaction to eliminate amino groups, carrying out hypophosphorous acid reduction to obtain an intermediate, and finally, carrying out nitro reduction by using iron powder, and preparing 2-chloro-6-methylaniline through a one-pot reaction. The method has the advantages of short reaction steps, mild reaction conditions, high product yield and low cost, and provides a universal new method for preparing the 2-chloro-6-methylaniline.
Highly selective hydrogenation of halogenated nitroarenes over Ru/CN nanocomposites by: In situ pyrolysis
Yue, Shengnan,Wang, Xueguang,Li, Shaoting,Sheng, Yao,Zou, Xiujing,Lu, Xionggang,Zhang, Chunlei
, p. 11861 - 11869 (2020/07/28)
A highly chemoselective and recyclable ruthenium catalyst for the hydrogenation of halogenated nitroarenes has been prepared via the simple in situ calcination of a mixture of melamine, glucose and ruthenium trichloride. Superfine Ru particles (2.3 ± 0.3 nm) were obtained and highly dispersed in the nitrogen-doped carbon matrix. The Ru/CN catalyst smoothly transforms a variety of halogenated nitroarenes to the corresponding haloanilines with high intrinsic activity (e.g. TOF = 1333 h-1 for p-chloronitrobenzene) and selectivity of more than 99.6percent. Furthermore, through an analysis of the products in the reaction process, it was concluded that there are two parallel reaction pathways (a direct pathway and an indirect pathway) for the hydrogenation of aromatic nitro compounds over the Ru/CN catalyst, and the direct pathway was proved to be dominant in catalyzing the intermediates. This journal is
Catalyst-Controlled Regioselective Chlorination of Phenols and Anilines through a Lewis Basic Selenoether Catalyst
Dinh, Andrew N.,Maddox, Sean M.,Vaidya, Sagar D.,Saputra, Mirza A.,Nalbandian, Christopher J.,Gustafson, Jeffrey L.
, p. 13895 - 13905 (2020/11/03)
We report a highly efficient ortho-selective electrophilic chlorination of phenols utilizing a Lewis basic selenoether catalyst. The selenoether catalyst resulted in comparable selectivities to our previously reported bis-thiourea ortho-selective catalyst, with a catalyst loading as low as 1%. The new catalytic system also allowed us to extend this chemistry to obtain excellent ortho-selectivities for unprotected anilines. The selectivities of this reaction are up to >20:1 ortho/para, while the innate selectivities for phenols and anilines are approximately 1:4 ortho/para. A series of preliminary studies revealed that the substrates require a hydrogen-bonding moiety for selectivity.
Preparation method of 2-chloro-6-methylaniline
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, (2019/08/20)
The invention relates to the field of chemistry, and in particular relates to a preparation method of high-purity 2-chloro-6-methylaniline. The preparation method of the 2-chloro-6-methylaniline comprises the following steps: preparing sodium 4-acetamido-3-methylbenzenesulfonate by using 4-amino-3-methylbenzenesulfonic acid and acetic anhydride in the presence of an acid binding agent; performinga chlorination reaction on the sodium 4-acetamido-3-methylbenzenesulfonate in the presence of a chlorination reagent to prepare 2-chloro-4-acetylamino-3-methylbenzenesulfonic acid; and performing a decarboxylation reaction on the 2-chloro-4-acetylamino-3-methylbenzenesulfonic acid to obtain the 2-chloro-6-methylaniline. According to the preparation method provided by the invention, through amino protection, chlorination, decarboxylation reactions and use of a specific sulfone solvent, an occurrence of side reactions in the reactions is reduced, a waste liquid is non-toxic and harmless, and thereaction operation and the post treatment method are simple.
Copper(ii)-catalyzed c-n coupling of aryl halides and n-nucleophiles promoted by quebrachitol or diethylene glycol
Chen, Guoliang,Chen, Yuanguang,Du, Fangyu,Fu, Yang,Wu, Ying,Zhou, Qifan
supporting information, p. 2161 - 2168 (2019/11/25)
Herein, we report the natural ligand quebrachitol (QCT) as a promoter for a Cu(II) catalyst, which is highly effective for N-Arylation of various amines and related aryl halides. A series of diarylamine derivatives were obtained in high yields by using diethylene glycol (DEG) as both ligand and solvent. The C-N coupling reactions proceed under mild conditions and exhibit good functional group tolerance.
Halide ion trapping of nitrenium ions formed in the Bamberger rearrangement of N-arylhydroxylamines. Lifetime of the parent phenylnitrenium ion in water
Fishbein,McClelland
, p. 1321 - 1328 (2007/10/03)
The data of p-aminophenol, the product of Bamberger rearrangement, Were analyzed by a mechanism involving rate-limiting formation of the appropriate arylnitrenium ion followed by product-determining steps in involving trapping by the solvent or by the added halide. The possibility that a portion of the halide-trapped products were derived from a pre-association mechanism was also include. Kinetic analyses then produced kBr:kw and kCl:kw ratios for two limiting cases, one involving pre-association with an equilibrium constant Kas = 0.3, and one ignoring pre-association. From an azide:water ratio (kAz:kw) previously determined for the 2,6-dimethylphenylnitrenium, kBr was concluded to lie in the range (4-5) × 109 M-1 s-1 for all of the nitrenium ions of this study. This range for kBr then led to kw values of (1-2) × 109 s-1 (2,5-Me2), (2-3) × 109 s-1 (2-Me), and (4-8) × 109 s-1 (parent and 2-Cl), where the ranges reflect uncertainties in the exact value of kBr and in the contribution from pre-association. The lifetime of the parent phenylnitrenium ion in water at one molar ionic strength is concluded to lie in the range 125-250 ps.
3-amino-5-methyl-1H-pyrazole-4-carboxylic acids and esters thereof as anticonvulsants, muscle relaxants and anxiolytics
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, (2008/06/13)
A novel method of controlling epilepsy, muscle tension, muscular spasticity, and anxiety in living animal bodies by administering compounds of the formula: STR1 wherein: R1 is hydrogen, loweralkyl or a pharmaceutically acceptable cation; R2 and R3, same or different, are hydrogen, loweralkyl, aryl, cycloalkyl, loweralkenyl, 1-adamantyl, heterocyclicaminoalkyl, diloweralkylaminoloweralkyl, or R2 with R3 and adjacent nitrogen may form a heterocyclic ring structure; and the pharmaceutical acceptable acid salts, and tautomeric isomers thereof; and novel pharmaceutical compositions therefor are disclosed.