O-bromonitrobenzene synthesis production process

Abstract

The invention provides an o-bromonitrobenzene synthesis production process, and is related to the technical field of chemical engineering. According to the invention, o-bromonitrobenzene is prepared through a synthesis reaction of a cuprous bromide solution prepared through a reduction reaction and a diazonium salt solution prepared through a diazotization reaction. The process provided by the invention has the following advantages: preparation is convenient and simple; the process is environment-friendly and pollution-free; the raw materials are easy to obtain; equipment investment is low; product purity is high; operation is easy; the prepared o-bromonitrobenzene has good application effect; and the prepared o-bromonitrobenzene is safe and reliable.

Description

technical field

[0001] The invention relates to the technical field of chemical industry, in particular to a production process for the synthesis of o-bromonitrobenzene. Background technique

[0002] o-Bromonitrobenzene is a yellow powder solid, which is light yellow when precipitated from ethanol, with a flash point of 87.8°C, a boiling point of 261°C, and a relative density of 1.719g / cm 3 . It is irritating to the eyes, respiratory system and skin. O-bromonitrobenzene is an important pharmaceutical intermediate. At present, the method of industrial production of o-bromonitrobenzene is still relatively traditional. This traditional production method has a low yield , low purity, serious pollution and other problems, and the production process is relatively complicated, which is difficult to meet the needs of human beings. Contents of the invention

[0003] The technical problem to be solved by the present invention is to provide a production process for the synthesis of...

Examples

Embodiment 1

[0023] A production technique for the synthesis of o-bromonitrobenzene, comprising the following process steps,

[0024] (1) Reduction reaction

[0025] a. Select the first enamel reaction kettle as the reaction vessel, add 400kg of water into the first enamel reaction kettle, start stirring, and add 25kg of crystalline copper sulfate, 5kg of copper powder, 70kg of crystalline sodium bromide and 10kg of concentrated sulfuric acid.

[0026] b. Stir the mixture in the above step a, turn on the steam after stirring evenly, heat and reflux for 3.0h, until the color of the solution turns yellow, after heating and reflux, if the solution is still blue, add 5-7kg of sodium bisulfite Solution, promptly obtain cuprous bromide solution for subsequent use,

[0027] (two) diazotization

[0028] a. Select the second enamel reaction kettle and add 40kg of concentrated sulfuric acid into the second enamel reaction kettle, start stirring and then add 240kg of ice cubes and 25kg of o-nitroan...

Embodiment 2

[0037] A production technique for the synthesis of o-bromonitrobenzene, comprising the following process steps,

[0038] (1) Reduction reaction

[0039] a. Select the first enamel reaction kettle as the reaction vessel, add 450kg of water into the first enamel reaction kettle, start stirring, and add 27kg of crystalline copper sulfate, 8kg of copper powder, 75kg of crystalline sodium bromide and 13kg of concentrated sulfuric acid.

[0040] b. Stir the mixture in the above step a, turn on the steam after stirring evenly, heat and reflux for 3.5h, until the color of the solution turns yellow, after heating and reflux, if the solution is still blue, add 5-7kg of sodium bisulfite Solution, obtain cuprous bromide solution for subsequent use.

[0041] (two) diazotization

[0042] a. Select the second enamel reaction kettle and add 45kg of concentrated sulfuric acid into the second enamel reaction kettle, start stirring and then add 250kg of ice cubes and 30kg of o-nitroaniline, an...

technical field

[0001] The invention relates to the technical field of chemical industry, in particular to a production process for the synthesis of o-bromonitrobenzene. Background technique

[0002] o-Bromonitrobenzene is a yellow powder solid, which is light yellow when precipitated from ethanol, with a flash point of 87.8°C, a boiling point of 261°C, and a relative density of 1.719g / cm 3 . It is irritating to the eyes, respiratory system and skin. O-bromonitrobenzene is an important pharmaceutical intermediate. At present, the method of industrial production of o-bromonitrobenzene is still relatively traditional. This traditional production method has a low yield , low purity, serious pollution and other problems, and the production process is relatively complicated, which is difficult to meet the needs of human beings. Contents of the invention

[0003] The technical problem to be solved by the present invention is to provide a production process for the synthesis of...

Examples

Embodiment 1

[0023] A production technique for the synthesis of o-bromonitrobenzene, comprising the following process steps,

[0024] (1) Reduction reaction

[0025] a. Select the first enamel reaction kettle as the reaction vessel, add 400kg of water into the first enamel reaction kettle, start stirring, and add 25kg of crystalline copper sulfate, 5kg of copper powder, 70kg of crystalline sodium bromide and 10kg of concentrated sulfuric acid.

[0026] b. Stir the mixture in the above step a, turn on the steam after stirring evenly, heat and reflux for 3.0h, until the color of the solution turns yellow, after heating and reflux, if the solution is still blue, add 5-7kg of sodium bisulfite Solution, promptly obtain cuprous bromide solution for subsequent use,

[0027] (two) diazotization

[0028] a. Select the second enamel reaction kettle and add 40kg of concentrated sulfuric acid into the second enamel reaction kettle, start stirring and then add 240kg of ice cubes and 25kg of o-nitroan...

Embodiment 2

[0037] A production technique for the synthesis of o-bromonitrobenzene, comprising the following process steps,

[0038] (1) Reduction reaction

[0039] a. Select the first enamel reaction kettle as the reaction vessel, add 450kg of water into the first enamel reaction kettle, start stirring, and add 27kg of crystalline copper sulfate, 8kg of copper powder, 75kg of crystalline sodium bromide and 13kg of concentrated sulfuric acid.

[0040] b. Stir the mixture in the above step a, turn on the steam after stirring evenly, heat and reflux for 3.5h, until the color of the solution turns yellow, after heating and reflux, if the solution is still blue, add 5-7kg of sodium bisulfite Solution, obtain cuprous bromide solution for subsequent use.

[0041] (two) diazotization

[0042] a. Select the second enamel reaction kettle and add 45kg of concentrated sulfuric acid into the second enamel reaction kettle, start stirring and then add 250kg of ice cubes and 30kg of o-nitroaniline, an...