80-07-9Relevant articles and documents
Method for synthesizing 4, 4 '-dichlorodiphenyl sulfone by using sulfoxide oxidation method
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Paragraph 0024-0026, (2021/04/07)
The invention relates to a method for synthesizing 4, 4 '-diaminodiphenyl sulfone by a sulfoxide oxidation method. The method is characterized by comprising the following steps: putting 4, 4 '-dichlorodiphenyl sulfone, dichloropropane, water and a phase transfer catalyst into a reactor, heating to 50-95 DEG C after feeding is finished, slowly dropwise adding hydrogen peroxide, continuously reacting for 3-7 hours, cooling to 0-5 DEG C, filtering, washing a filter cake with water, and drying to obtain the finished product 4, 4'-dichlorodiphenyl sulfone. The method is short in reaction time, thorough in material reaction, high in product yield and low in production cost.
PROCESS FOR PRODUCING 4,4'-DICHLORODIPHENYL SULFONE
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Page/Page column 32-33, (2021/03/05)
The invention relates to a process for producing 4,4'-dichlorodiphenyl sulfone, comprising: (I) reacting thionyl chloride, chlorobenzene and aluminum chloride forming an intermediate reaction product and hydrogen chloride; (II) mixing aqueous hydrochloric acid and the intermediate reaction product to obtain an organic phase comprising 4,4'-dichlorodiphenyl sulfoxide and an aqueous phase; (III) cooling the organic phase to a temperature below the saturation point of 4,4'- dichlorodiphenyl sulfoxide to obtain a suspension; (IV) solid-liquid-separation of the suspension to obtain crystallized 4,4'-dichlorodiphenyl sulfoxide, and mother liquor; (V) washing the crystallized 4,4'-dichlorodiphenyl sulfoxide with a carboxylic acid to obtain carboxylic acid-wet 4,4'-dichlorodiphenyl sulfoxide; (VI) reacting the washed 4,4'-dichlorodiphenyl sulfoxide and an oxidizing agent in a carboxylic acid as solvent to obtain a reaction mixture comprising 4,4'-dichlorodiphenyl sulfone and carboxylic acid; (VII) separating the reaction mixture comprising 4,4'-dichlorodiphenyl sulfone and carboxylic acid into a residual moisture comprising 4,4'-dichlorodiphenyl sulfone as crude product and a liquid phase comprising carboxylic acid.
A PROCESS FOR OBTAINING 4,4'-DICHLORODIPHENYL SULFONE
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Page/Page column 22; 23, (2021/03/05)
The invention relates to a process for obtaining 4,4'-dichlorodiphenyl sulfone from an organic mixture comprising 4,4'-dichlorodiphenyl sulfone and a linear C6 to C10 carboxylic acid as organic solvent, comprising: (a) cooling the organic mixture by (a1a) mixing the organic mixture with water in a crystallization vessel to obtain a liquid mixture; (a1b) cooling the liquid mixture obtained in (a1a) to a temperature below the saturation point of 4,4'-dichlorodiphenyl sulfone by (i) reducing the pressure in the crystallization vessel to a pressure at which the water starts to evaporate, (ii) condensing the evaporated water by cooling, (iii) mixing the condensed water into the liquid mixture in the crystallization vessel, to obtain a suspension comprising crystallized 4,4'-dichlorodiphenyl sulfone; or by (a2) bringing the organic mixture into contact with at least one coolable surface and thereby reducing the temperature in the organic mixture with a cooling rate in the range from 5 to 50 K/h until a temperature in the range from 10 to 30°C is reached, wherein the organic mixture and the at least one coolable surface have a temperature difference which is kept during the whole cooling process in the range from 1 to 30 K to obtain a suspension comprising crystallized 4,4'-dichlorodiphenyl sulfone. (b) carrying out a solid-liquid-separation of the suspension obtained in (a1b) or in (a2) to obtain a residual moisture containing solid 4,4'-dichlorodiphenyl sulfone as product and mother liquor comprising the organic solvent and water.