- Fenhexamid and analysis method thereof
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The invention discloses fenhexamid and an analysis method thereof. The fenhexamid is prepared from aniline, hydrochloric acid, sodium nitrite solution, 2,3-dichlorophenol, sodium hydroxide, water, ethyl alcohol, sodium hydrosulfite, 1-methyl cyclohexanoic acid, methylene dichloride, N,N-dimethyl formamide, thionyl chloride, ethyl acetate and triethylamine. The fenhexamid content reaches 98% or above, and yield reaches 86-87%; in a fenhexamid analysis process, sodium hydrosulfite adopted for azo reduction for generating 2,3-dichloro-4-hydroxylaniline is high in reducibility and quick in weak alkaline reduction reaction, and the conversion rate reaches 98% or above by cross input of sodium hydroxide and sodium hydrosulfite; pH is kept in a range of 6-7 by acid reflux after adding of sodium hydrosulfite. Fenhexamid production conditions are mild, and easiness in operation, high safety, high total yield, low cost and suitableness for large-scale production and application to enterprises are realized.
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Paragraph 0053; 0059-0060; 0069; 0076
(2018/11/03)
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- Preparation method of 2,3-dichloro-4-hydroxyaniline
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The invention discloses a preparation method of 2,3-dichloro-4-hydroxyaniline. The preparation method comprises the steps of adding a reaction raw material 2,3-dichloro-4-phenylazo phenol and a reductant sodium borohydride into an ethanol solution, reacting at 0-25 DEG C for 2-6 hours, cooling to the room temperature after the reaction, regulating pH to 7, extracting by virtue of ethyl acetate, drying by virtue of anhydrous sodium sulfate, then carrying out rotary evaporation to remove the solvent, recrystallizing with methylbenzene, and finally drying so as to obtain 2,3-dichloro-4-hydroxyaniline. According to the preparation method of 2,3-dichloro-4-hydroxyaniline, a catalytic reduction method for utilizing hydrogen/metals at a pressurization condition is avoided, expensive and inflammable Raney nickel or other metal catalysts are not used, the operation is simple, conditions are mild, the yield can reach 90% or above, and the reaction cost is low. The preparation method is applicable to large-scale industrial production.
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Paragraph 0038; 0039; 0040
(2016/10/10)
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- Process for preparing 4-hydroxyanilines
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The application describes a process for preparing 4-hydroxyanilines by the reaction of phenols with diazonium salts and subsequent reduction.
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- Process for the preparation of p-amino-phenols
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p-Amino-phenols are advantageously prepared by catalytic hydrogenation of the aromatic nitro compounds on which they are based in a reaction medium of aqueous sulphuric acid in the sense of a Bamberger rearrangement at elevated temperature by a procedure in which the reaction medium additionally contains a water-miscible organic solvent.
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- Cycloalkylcarboxanilides
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This invention relates to cycloalkylcarboxanilides of the formula STR1 in which R represents halogen or halogenoalkyl, R1 represents halogen, alkyl or halogenoalkyl, n represents the numbers 0, 1, 2 or 3, X1, X2, X3 and X4 independently of one another represent hydrogen, halogen, alkyl, halogenoalkyl, alkoxy, halogenoalkoxy, alkylthio or halogenoalkylthio, and Z represents hydrogen, which have the utility as pesticides and fungicides.
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