Synthetic process for efficiently and continuously producing 4,4-dichlorodiphenyl sulfone

Abstract

The invention discloses a synthetic process for efficiently and continuously producing 4,4-dichlorodiphenyl sulfone, which comprises the following steps: carrying out Friedel-Crafts acylation on thionyl chloride and excessive chlorobenzene under the action of a lewis acid catalyst, carrying out pyrohydrolysis and adding chlorobenzene to carry out layering after the reaction is finished, adding anoxidizing agent into a sulfoxide organic layer to carry out oxidization, adding activated carbon to carry out decoloration and filtering; cooling filtrate and carrying out rejection filtration to obtain 4,4-dichlorodiphenyl sulfone. The synthetic process has the advantage that chlorobenzene not only is a raw material, but also is a reaction solvent, so that cross use of various solvents is avoided. Particularly, use of a great amount of acetic acid used as an oxidation reaction solvent is avoided, and corrosion to equipment and environmental pollution are avoided. In the integral process flow,separation and extraction of an intermediate 4,4-dichlorodiphenyl sulfoxide are avoided, so that production time of the product is greatly shortened, and production cost is saved. By using hydrogen peroxide, acetic acid and concentrated sulfuric acid as mixed oxidizing agents, oxidization capacity of hydrogen peroxide is greatly improved, yield and purity of the product are greatly improved, yield of the product reaches 90% or more, and purity of the product is greater than 99.8%.

Description

technical field

[0001] The invention relates to an organic synthesis process, in particular to a synthesis process for efficient and continuous production of 4,4-dichlorodiphenyl sulfone. Background technique

[0002] 4. 4'-Dichlorodiphenylsulfone (DDS) is the main intermediate for the manufacture of polysulfone engineering plastics, and it is also the raw material for the synthesis of 4,4'-diaminodiphenylsulfone, a drug for the treatment of leprosy. With the rapid development of polysulfone resins, the demand for DDS has also increased rapidly. Therefore, it is increasingly important to study the synthesis method and process improvement of the compound.

[0003] There are many industrial synthesis methods of DDS, which can be divided into the following methods according to the classification of sulfonating agents:

[0004] 1) Chlorosulfonic acid method: due to the use of chlorosulfonic acid in this method, there are problems such as storage, transportation and use of the ...

Examples

Embodiment 1

[0019] Add 60.0 g of anhydrous aluminum trichloride and 160.0 g of chlorobenzene into a 500 mL three-necked flask, and start stirring. Slowly add 52.5 g of thionyl chloride dropwise to the system, and control the temperature not higher than 50°C. After the addition was completed, the reaction was continued for 1 h. After the reaction was completed, the reaction solution was slowly added into 120 mL of hot water at 90°C, and after the addition was completed, the reaction was continued with stirring at 90°C for 2h. After the reaction is over, continue to add 100 chlorobenzene to the system, and separate layers after the system dissolves. The water layer was removed, and the temperature of the organic layer was lowered to 80° C. and kept stirring. 7.5 g of concentrated sulfuric acid and 25.0 g of acetic acid were slowly added dropwise to the organic layer. After the system was evenly stirred, 55.0 g of 35% hydrogen peroxide was slowly added dropwise to the system. After the a...

Embodiment 2

[0021] Add 65.0 g of anhydrous aluminum trichloride and 200.0 g of chlorobenzene into a 500 mL three-necked flask, and start stirring. Slowly add 52.5 g of thionyl chloride dropwise to the system, and control the temperature not higher than 50°C. After adding, continue to keep warm for 2h. After the reaction was completed, the reaction solution was slowly added into 130 mL of hot water at 90°C, and after the addition was completed, the reaction was continued with stirring at 90°C for 3h. After the reaction is over, continue to add 100 chlorobenzene to the system, and separate layers after the system dissolves. The water layer was removed, and the temperature of the organic layer was lowered to 80° C. and kept stirring. 7.5 g of concentrated sulfuric acid and 30.0 g of acetic acid were slowly added dropwise to the organic layer. After the system was evenly stirred, 60.0 g of 35% hydrogen peroxide was slowly added dropwise to the system. After the addition, the system was re...

technical field

[0001] The invention relates to an organic synthesis process, in particular to a synthesis process for efficient and continuous production of 4,4-dichlorodiphenyl sulfone. Background technique

[0002] 4. 4'-Dichlorodiphenylsulfone (DDS) is the main intermediate for the manufacture of polysulfone engineering plastics, and it is also the raw material for the synthesis of 4,4'-diaminodiphenylsulfone, a drug for the treatment of leprosy. With the rapid development of polysulfone resins, the demand for DDS has also increased rapidly. Therefore, it is increasingly important to study the synthesis method and process improvement of the compound.

[0003] There are many industrial synthesis methods of DDS, which can be divided into the following methods according to the classification of sulfonating agents:

[0004] 1) Chlorosulfonic acid method: due to the use of chlorosulfonic acid in this method, there are problems such as storage, transportation and use of the ...

Examples

Embodiment 1

[0019] Add 60.0 g of anhydrous aluminum trichloride and 160.0 g of chlorobenzene into a 500 mL three-necked flask, and start stirring. Slowly add 52.5 g of thionyl chloride dropwise to the system, and control the temperature not higher than 50°C. After the addition was completed, the reaction was continued for 1 h. After the reaction was completed, the reaction solution was slowly added into 120 mL of hot water at 90°C, and after the addition was completed, the reaction was continued with stirring at 90°C for 2h. After the reaction is over, continue to add 100 chlorobenzene to the system, and separate layers after the system dissolves. The water layer was removed, and the temperature of the organic layer was lowered to 80° C. and kept stirring. 7.5 g of concentrated sulfuric acid and 25.0 g of acetic acid were slowly added dropwise to the organic layer. After the system was evenly stirred, 55.0 g of 35% hydrogen peroxide was slowly added dropwise to the system. After the a...

Embodiment 2

[0021] Add 65.0 g of anhydrous aluminum trichloride and 200.0 g of chlorobenzene into a 500 mL three-necked flask, and start stirring. Slowly add 52.5 g of thionyl chloride dropwise to the system, and control the temperature not higher than 50°C. After adding, continue to keep warm for 2h. After the reaction was completed, the reaction solution was slowly added into 130 mL of hot water at 90°C, and after the addition was completed, the reaction was continued with stirring at 90°C for 3h. After the reaction is over, continue to add 100 chlorobenzene to the system, and separate layers after the system dissolves. The water layer was removed, and the temperature of the organic layer was lowered to 80° C. and kept stirring. 7.5 g of concentrated sulfuric acid and 30.0 g of acetic acid were slowly added dropwise to the organic layer. After the system was evenly stirred, 60.0 g of 35% hydrogen peroxide was slowly added dropwise to the system. After the addition, the system was re...