2,5-Dimethoxy-4-chloroaniline synthesis

Yield:6358-64-1 99.1%

Reaction Conditions:

with hydrogen in methanol at 70 - 80; under 750.075 - 7500.75 Torr;Large scale;Pressure;

Steps:

1 Example 1
To 100 kg of 4-chloro-2,5-dimethoxy nitrobenzene production of 4-chloro -2,5-dimethoxy aniline, for example,The catalyst used was a supported metal activated carbon catalyst,The total amount of catalyst used in the production process is 0.1-3% (0.1-3 kg) of raw materials, and the total amount of methanol is 8.5 times (850 kg) of raw materials. In continuous production, 4-chloro- Nitrobenzene, methanol and the catalyst is added according to the flow rate of flow, the specific process is as follows:
1, start the feed pump,Adjust the flow rate of 540 L / h, according to the flow rate of access to a reduction kettle,While the catalyst and methanol also lead into a reduction kettle,Adjust the stirring speed of a reactor in 200 r / min or so,Then, hydrogen gas was introduced to carry out the reduction reaction,Hydrogen at 0.1Mpa when the reaction began,In the present embodiment, the reduction reaction was carried out while keeping the hydrogen pressure at 0.3 to 1.0 MPa.Hydrogenation reaction at the same time release heat through the cooling water regulator pot temperature, the pot temperature is always controlled between 70-80 ,Using sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate and other mediation reaction solution pH between 7-8.
4, from the three reactor overflow out of the reaction solution to the settler,The catalyst-carrying reducing solution is separated by solid-liquid after settling,When the settler level is 83%Open settler discharge valve,Open self-regulating valve,The settler lower solid content of the liquid layer into the filter,Filtering out a small amount of the catalyst entrained in the liquid into the reducing liquid reduction tank,The reducing solution is 4-chloro-2,5-dimethoxyaniline solution;Open the settler bottom discharge valve,Outflow of the liquid layer with more solid, as the catalyst.
The product obtained according to the method described above was analyzed to give 100% conversion of 4-chloro-2,5-dimethoxy nitrobenzene, selectivity of 4-chloro-2,5-dimethoxyaniline 99.5% , 4-chloro-2,5-dimethoxyaniline content of 99.5%, the yield of 99.1%.

References:

Jinan Herun Chemical Technology Co., Ltd.;Hou, Weibo;Han, Longkai;Tang, Guowu;Wang, Chao;Li, Juan;Lu, Bo;Si, Lipeng;Zhao, Enfeng;Wang, Guang CN105949069, 2016, A Location in patent:Paragraph 0021; 0022; 0023; 0024; 0025; 0026

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