6358-64-1Relevant articles and documents
Preparation method of 4-chloro-2, 5-dimethoxyaniline
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Paragraph 0022; 0025-0026; 0029-0030; 0033-0040, (2020/02/14)
The invention relates to the technical field of organic synthesis, and particularly discloses a preparation method of 4-chloro-2, 5-dimethoxyaniline. The preparation method comprises the following steps that in the presence of a supported nickel catalyst, ethyl alcohol serves as a solvent, 4-chloro-2, 5-dimethoxynitrobenzene reacts with hydrazine hydrate, the 4-chloro-2, 5-dimethoxyaniline is obtained through separation from reaction liquid, and a carrier of the supported nickel catalyst is a TiO2-Al2O3 composite carrier. According to the preparation method of the 4-chloro-2, 5-dimethoxyaniline, provided by the invention, the use of a dehalogenation inhibitor and hydrogen can be effectively avoided, the process is simple, the operation is convenient, the preparation method is green and environment-friendly, safe and reliable, the cost is relatively low, and the product yield is greater than or equal to 95%.
Method for continuous hydrogenation production of 4-chloro-2,5-dimethoxyaniline
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Paragraph 0021; 0022; 0023; 0024; 0025; 0026, (2016/12/16)
The invention discloses a method for industrial continuous hydrogenation synthesis of 4-chloro-2,5-dimethoxyaniline. According to the method, 4-chloro-2,5-dimethoxy nitrobenzene and hydrogen are taken as raw materials, methyl alcohol is used as reaction solvent, methyl alcohol and a catalyst are added into a reduction kettle, and the raw materials 4-chloro-2,5-dimethoxy nitrobenzene and hydrogen are added too for reduction reaction; reaction of reaction liquid continues in a second reduction kettle and a third reduction kettle till conversion rate reaches 100%, and then the reaction liquid is crystallized to obtain the product. Reduction reaction is achieved through the three reduction kettles connected in sequence, raw material contact time is long, and raw material conversion rate can reach 100%; the obtained product is white powder, chromatographic purity is 99% or more, content is 99% or more and yield is 97% or more.
A hydrazine hydrate and catalytic reduction process for preparing 4 - chloro - 2, 5 - two-anisidine production process (by machine translation)
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Paragraph 0033; 0034, (2017/06/19)
A hydrazine hydrate and catalytic reduction process for preparing 4 - chloro - 2, 5 - two-anisidine production process, the reaction vessel is sequentially added in the water, FeCl3·6H2OandFeSO4·7H2O, adding activated carbon, dropping NaOH solution to adjust pH value, for filtering and washing the filter cake to make theFe (OH) 3clay, crushing and drying to obtain the catalyst; sequentially added to the reaction kettle in ethanol solvent, 4 - nitro - 2, 5 - dimethoxy chlorobenzene and the catalyst, uniform drop water [...] solution, for HPLC detection reaction process, until the 4 - nitro - 2, 5 - dimethoxy chlorobenzene is completely reduce the hydrazine hydrate, the temperature of the filter when the system, separate out the target product 4 - chloro - 2, 5 - two-anisidine, filtering the solution of catalyst to continue to apply the filter residue; the production of the catalyst are cheap, high catalytic efficiency, stable catalytic activity, environmental protection and pollution-free, the produced 4 - chloro - 2, 5 - two-anisidine high yield, high purity, and the quality is stable. (by machine translation)