Industrial production method of o-nitrobenzenesulfonyl chloride

Abstract

The invention discloses an industrial production method of o-nitrobenzenesulfonyl chloride. The method comprises the following steps that o-nitrochlorobenzene and sodium methyl mercaptide are subjected to an etherification reaction, filtering is conducted, an obtained filter cake is subjected to recrystallization, and through centrifugation separation and drying, a dry product of o-nitrobenzene dimethyl sulfide is obtained; the dry product of o-nitrobenzene dimethyl sulfide is subjected to a chlorination reaction in batches to obtain a wet crude product, an appropriate amount of hydrochloric acid is added in a chlorination reaction system, the chlorination reaction is carried out in a hydrophilic organic acid solvent, and the mole ratio of the o-nitrobenzene dimethyl sulfide to water during the chlorination reaction is 1:(5-15); a finished product of o-nitrobenzenesulfonyl chloride is obtained through refining and drying. Through HPLC detection, the content of the o-nitrobenzenesulfonyl chloride synthesized by means of the method is 98-98.5%; the yield is 0.72-0.75, the acquisition rate is 0.97 or above, the turbidity (ppm) is 1.5-2, and the melting point is 66-67 DEG C. By adopting the hydrophilic organic acid solvent, the problems about large-scale production discharging, yield and quality are solved, and meanwhile the purposes of mixed application and post-treatment separation of large-scale production water-soluble solvents are achieved.

Description

technical field [0001] The invention belongs to the technical field of industrial production of compounds, and in particular relates to an industrial production method of o-nitrobenzenesulfonyl chloride. Background technique [0002] O-nitrobenzenesulfonyl chloride is also known as 2-nitrobenzenesulfonyl chloride, brown or yellow needle-like crystals, with a low boiling point, soluble in ether, and can be used in medicine, high-grade dyes and special materials in the application field. Its structural formula is : [0003] [0004] The traditional o-nitrobenzenesulfonyl chloride is mainly synthesized by referring to BI1153, 161 process. Its specific synthetic steps are divided into two steps: [0005] 1) In the first step of the existing industrial production process, Na 2 S and sulfur are heated and refluxed in an organic solvent for 1 hour to obtain Na 2 S 2 solution; then by o-nitrochlorobenzene, 94% ethanol, add Na within 8 hours at 65°C 2 S 2 Solution reaction,...

AI Technical Summary

Problems solved by technology

[0013] In view of the deficiencies in the prior art, the industrial production method of o-nitrobenzenesulfonyl chloride uses 1-chloro-4-nitrobenzene as raw material production, which can eliminate the residual disulfide compound in the traditional process 1) product, and make the product The turbidity is controlled below 2ppm, which meets the requirements of liquid crystal materials for turbidity; the lipophilic and toxic solvent is replaced by a hydrophilic solvent to solve the problem of low purity and yield of the intermediate product o-nitroanisole in process 2). Low chlorine efficiency, low yield and unindustrialization caused by unevenness; use toluene and ethylbenzene with lower toxicity than monochlorobenzene for refining, and no need to add anhydrous sodium sulfate drying process, compared with traditional process, the process cost of the present invention is low, the process route is shortened, the toxicity of the solvent used is greatly reduced, the yield can reach 97%, and the HPLC content is more than or equal to 98%.

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