- A method for preparing 2, 4, 5 - trichloro phenol (by machine translation)
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The invention discloses a 2, 4, 5 - trichloro phenol industrial preparation method. The 2, 4, 5 - trichloro phenol industrial preparation method, in order to 2, 4 - dichloro nitrobenzene is used as the initial raw materials, by chlorine, reduction and diazo - sandmaier three-step reaction synthesis of 2, 4, 5 - trichloro phenol. The got in the course of 2, 4, 5 - trichloro phenol as yellow solid, purity 97.5%, each step the raw material conversion rate respectively reaches 100%, the whole process of the total yield up to 60%. (by machine translation)
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Paragraph 0010; 0013
(2019/02/27)
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- Control of the Stereochemistry of Four-co-ordinate Copper(II) Complexes by Pyridinecarboxamide Ligands: Crystal Structure, Spectral and Redox Properties
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Three copper(II) complexes 1>*H2O 1, 22> 2 and 32> 3 1 = N,N'-o-phenylenebis(pyridine-2-carboxamide); HL2 = N-phenylpyridine-2-carboxamide; HL3 = N-2,4,5-trichlorophenylpyridine-2-carboxamide> have beenn prepared and their stereochemical properties investigated.Complex 2 has been characterized by X-ray crystallography: space group P21/n, a = 10.853(4), b = 19.015(6), c = 10.293(3) Angstroem, β = 105.22(3) deg, Z = 4, R = 0.030, R' = 0.034 for 2938 observed reflections.Compared to the known square-pyramidal structure of 1 it is revealed that the deprotonated bidentate ligand L2 exerts a measureable degree of geometric control over the co-ordination sphere of 2 (distorted towards tetrahedral).Similar effects are also observed from absorption and EPR spectral results.The Cu(II)-Cu(I) redox potentials in dimethylformamide solution have been determined by cyclic voltammetry.Upon replacement of the tetradentate L1 ligand by two uninegative bidentate L2 or L3 ligands, of similar donor set, a marked positive shift (ca. 0.6-0.7 V) was observed, implying the predominance of structural effects.
- Ray, Manabendra,Mukherjee, Rabindranath,Richardson, John F.,Mashuta, Mark S.,Buchanan, Robert M.
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p. 965 - 970
(2007/10/02)
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- Hydrolysis and Fe2+-induced Reduction of N-Aryl -O-pivaloylhydroxylamines: Aqueous Solution Chemistry of Model Carcinogens.
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The N-aryl-O-pivaloylhydroxylamines, 1a-d, which serve as models for the carcinogenic metabolites of aromatic amines, decompose in aqueous media by heterolysis of the N-O bond.Substituent effects on rates of reaction and products of the decomposition of 1a-c are entirely consistent with the intermediacy of a singlet nitrenium ion.The least reactive compound in the series N-(4-nitrophenyl)-O-pivaloylhydroxylamine (1d) yields 4-nitroaniline (2d) as its major decomposition product.This material may be formed through H radical abstraction by a triplet ion, but a nitrene reaction appears to be more likely.In the presence of Fe2+ 1a-d undergo rapid reduction to the corresponding anilines 2a-d.This reaction requires complexation of the ester with Fe2+ and proceeds with heterolysis of the N-O bond since nearly quantitative yields of pivalic acid are isolated.The radical cations 25a-d appear to be the most likely precursors to the reduction products.
- Novak, Michael,Lagerman, Robert K.
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p. 4762 - 4769
(2007/10/02)
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- Water-soluble trisazo 8-amino-naphthol-1 dyes
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Very effective direct dyeing of cotton and other hydroxyl- or nitrogen-containing fibers is effected with water-soluble triasazo dyes having the formula: where A is a radical of a diazoconstituent and A3 is a radical of a coupling constituent STR1 and A1 or A2 or both can have their azo linkages reversed. These dyes are very fast particularly to washing and to perspiration, and are so effective with cotton that dye baths for such use are rapidly exhausted and the disposal of used bath is less of a problem.
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- Process for the production of halogenated aromatic primary amines
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Process for producing halogenated aromatic primary amines that may contain substituents such as methyl, ethyl, methoxy, and so on, by catalytic hydrogenation of halogenated aromatic nitro compounds in the presence both of a Raney nickel catalyst and of a dehalogenation inhibitor selected from the group consisting of dicyandiamide, cyanamide and calcium cyanamide, in an inert solvent at a temperature in the range from 40° to 150° C under an elevated hydrogen pressure, whereby any dehalogenated aromatic primary amine impurity in the halogenated aromatic primary amine product is held to an acceptable minimum so that the halogenated aromatic amines may be produced in a high state of purity.
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- One step diazotization coupling process
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A process for producing metal-free azo pigments in purely organic liquid or aqueous/organic liquid containing at most 10% of water calculated on the total weight of the suspension is described. In this one-step process, a suitable aromatic amine is diazotized without isolation of the obtained diazo compound and coupled with a coupling component. Both reactions are carried out in purely or essentially organic medium. The latter consists essentially of such amount of an organic liquid that a substantial portion either of the diazo component or of the coupling component or of both these reactants remain undissolved. Both reactants must be free from sulphonic acid groups. If the resulting azo pigment contains carboxylic acid groups, these can be subsequently converted to the corresponding amido or ester groups.
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- Azo pigments derived from 2-hydroxy-3-carboxynaphthalene containing a substituted or unsubstituted phthalimide
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Azo pigments derived from 2-hydroxy-3-carboxy-naphthalene and containing a substituted or unsubstituted phthalimide radical. The majority give red colorations and due to their excellent fastness properties are particularly valuable for use in surface coatings and resins.
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