16867-03-1Relevant articles and documents
Synthesis method of 2-amino-3-hydroxypyridine
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Paragraph 002; 0024-0025; 0028-0029; 0032-0033; 0036-0037, (2021/03/31)
The invention discloses a synthesis method of 2-amino-3-hydroxypyridine, which comprises the following steps: reacting furfural serving as a raw material with haloid and sulfamate in an acid water solution to obtain 2-imino-3-hydroxypyridine sulfonic acid, and heating and hydrolyzing the 2-imino-3-hydroxypyridine sulfonic acid to obtain 2-amino-3-hydroxypyridine sulfate; and finally, adjusting thepH value by using alkali to obtain the 2-amino-3-hydroxypyridine. By using the method provided by the invention, the product yield is high, furfural which is cheap and easy to obtain is used as a rawmaterial, substances with higher toxicity are prevented from being used in the production process, the reaction condition is mild and no waste gas is generated in the reaction process; the solutionsof the method are all aqueous solution, and wastewater generated in the production process is a halite solution and a sulfate solution, which can be marketed as byproducts; the method reduces enterprise three-waste treatment cost, changes wastes into valuables, reduces environmental pollution from the source, reduces enterprise production cost and improves income.
2-amino-3-pyridone as well as preparation method and preparation method thereof
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Paragraph 0040-0077, (2019/04/11)
The invention provides 2-amino-3-pyridone as well as a preparation method and a preparation method thereof, and relates to the field of chemical reagent analysis. The preparation method of the 2-amino-3-pyridone comprises the following steps of introducing chlorine gas or bromine into a furfural water solution to perform loop opening reaction; reacting obtained mixed liquid with an ammonia sulfamate solution to obtain 2-amino-3-pyridone sulfonate; hydrolyzing the 2-amino-3-pyridone sulfonate under the basic condition to obtain brown 2-amino-3-pyridone with the yield being higher than 75 percent. The yield is effectively improved. The furfural is used as raw materials; the cost is effectively reduced. Through refining by a refining method provided by the invention, the white 2-amino-3-pyridone is obtained; the yield of the white 2-amino-3-pyridone is greater than or equal to 70 percent; the purity is higher than 99 percent.
Hexafluoro-2-propanol-assisted quick and chemoselective nitro reduction using iron powder as catalyst under mild conditions
Chen, Xu-Ling,Ai, Bai-Ru,Dong, Yu,Zhang, Xiao-Mei,Wang, Ji-Yu
supporting information, p. 3646 - 3649 (2017/08/23)
Hexafluoro-2-propanol as the promoter for the quick nitro reduction using a combination of iron powder and 2 N HCl aqueous solution is reported. This methodology has several positive features, as it is of room temperature, remarkably short reaction time. A wide range of substrates including those bearing reducible functional groups such as aldehyde, ketone, acid, ester, amide, nitrile, halogens, even allyl, propargyl and heterocycles are chemoselectively reduced in good to excellent yields, even on gram scale. Notably, the highly selective reduction of 3-nitrophenylboronic acid is achieved quantitatively. The reduction is also tolerant of common protecting groups, and aliphatic nitro compound, 1-nitrooctane can be reduced successfully.
Transfer hydrogenation of nitroarenes with hydrazine at near-room temperature catalysed by a MoO2 catalyst
Zhang, Chaofeng,Lu, Jianmin,Li, Mingrun,Wang, Yehong,Zhang, Zhe,Chen, Haijun,Wang, Feng
, p. 2435 - 2442 (2016/05/19)
We present an experimental and computational study of the elementary steps of hydrazine hydrogen transfer on crystalline MoO2, and demonstrate its unique bifunctional metallic-basic properties in a catalytic hydrogenation reaction. Density functional theory (DFT) calculations suggest that the stepwise hydrogen transfer via the prior cleavage of the N-H bond rather than the N-N bond, is the key step to create the dissociated hydride and proton species on the dual Mo and O sites, marking its difference with common oxides. Crystalline MoO2 shows exceptionally high chemoselectivity toward the nitro reduction over C=C, C≡C, and C≡N groups at room temperature and lower, down to 0 °C, rendering it as a promising catalytic material for hydrogenation reactions.
Transfer hydrogenation of nitroarenes to arylamines catalysed by an oxygen-implanted MoS2 catalyst
Zhang, Chaofeng,Zhang, Zhixin,Wang, Xu,Li, Mingrun,Lu, Jianmin,Si, Rui,Wang, Feng
, p. 85 - 93 (2016/07/25)
We present an efficient approach for chemoselective synthesis of various functionalized arylamines from nitroarenes over an oxygen-implanted MoS2 catalyst (O-MoS2). The HRTEM, XRD, XPS, Raman, EXAFS and NH3-TPD characterizations show the existence of MoIVOx structure and abundant coordinative unsaturated (CUS) Mo sites in the 2D-layer structure of O-MoS2. In the transfer hydrogenation of nitroarenes with hydrazine hydrate, the MoIVOx structure works as the catalytic active center. The N2H4 selectively decomposes to the active hydrogen species in polar electronic states (Hδ? and Hδ+), which show high chemoselectivity toward the nitro reduction over [Formula presented], [Formula presented], and [Formula presented] groups. The O-MoS2 catalyst can be recovered in a facile manner from the reaction mixture and recycled four times without any significant loss of activity.
One step hair coloring compositions using salts
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, (2008/06/13)
A hair coloring composition comprising the following two compositions which are mixed just prior to application to the hair: (a) a composition comprising a water-soluble peroxygen oxidizing agent; and (b) a composition comprising one or more oxidative hair coloring agents selected from the group consisting of an aromatic diamine, an amino phenol, a naphthol, a polyhydric phenol, a catechol and mixtures thereof; wherein the composition comprising one or more oxidative hair coloring agents further comprises al least one water soluble carbonate releasing salts; and optionally a water soluble ammonium salt, is described.
Transition metal complexes as dye forming catalysts in hair coloring compositions
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, (2008/06/13)
A hair coloring composition comprising a first composition which comprises: (a) a dye forming transition metal salt or complex; which is first applied to the hair; and a second composition which comprises the following two compositions which are mixed just prior to application to the hair: (a) a composition comprising a water-soluble peroxygen oxidizing agent; and (b) a composition comprising one or more oxidative hair coloring agents selected from the group consisting of an aromatic diamine, an aminophenol, a polyhydric phenol a catechol and mixtures thereof.
Enhanced color deposition for hair with sequestering agents
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, (2008/06/13)
Hair coloring compositions which comprise: (A) non-nitrogenous chelating agents from the group consisting of polyphosphate; phosphonates; hydroxycarboxylates; polyacrylates; zeolite; and mixtures thereof; (B) an oxidative dye primary intermediate; and (C) an oxidative dye coupler; (D) and water are described. The present invention also relates to a method for coloring hair which comprises contacting said hair with a hair coloring composition as described above.
Cleavage of aromatic methyl ethers by chloroaluminate ionic liquid reagents
Kemperman, Gerardus J.,Roeters, Theodorus A.,Hilberink, Peter W.
, p. 1681 - 1686 (2007/10/03)
We have discovered serendipitously that chloroaluminate ionic liquids can cleave aromatic methyl ethers under surprisingly mild conditions. Three ionic liquids, viz. [TMAH]-[Al2Cl7], [BMIM][Al2Cl7], and [EMIM][Al2Cl6I], and aluminum chloride were compared in the selective demethylation of 4,5-dimethoxyindanone at the 4-methoxy-function. The ionic liquids exhibited a remarkably high selectivity (96:4) in comparison with aluminum chloride (70:30). In addition, the reaction time was drastically shortened when the ionic liquids were used. Interestingly, the three ionic liquids displayed the same reactivity in the demethylation of 4,5-dimethoxyindanone. Considering the lower cost and the bulk availability of the precursors of [TMAH][Al2Cl7], we conclude that this is the most attractive ionic liquid from an industrial point of view. To make the large-scale application of [TMAH][Al2Cl7] feasible, we have developed a safe upscalable method for its preparation. Furthermore, the scope of ether cleavage by the ionic liquid reagent [TMAH][Al2Cl7] was investigated and it was found that aromatic methyl-, al- lyl-, and benzyl-ether cleavage is applicable to a variety of heterocyclic compounds. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
IL-8 receptor antagonists
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, (2008/06/13)
The present invention relates to the use of phenyl ureas in the treatment of disease states mediated by the chemokine, Interleukin-8 (IL-8).
