SU859360A1 - Method of preparing diphenylsulfide - Google Patents

Description

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The invention relates to a process for the preparation of diphenylsulfide, which finds use as additives to polymers and an effective herbicide, as well as in the synthesis of medicinal substances.

There are known methods for the production of a definyl sulfide, for example, by reacting benzene with sulfur monochloride in the presence of aluminum chloride in a yield of 81-83% FI, by reducing the sodium bis (2-methoxy) aluminum alum hydride in benzene at boiling in yield up to 97% 21, trichloromethylphenyl sulfide with Grignard's reagent with a yield of 47% GZ or intermediates by desulfurization of triophenol at 530-580 ° C in an inert gas atmosphere in a flow-through system with a yield of 48%. 43 To the disadvantages of these methods are either difficult to use pnyh initial compounds, or low yields of the target product, or the complexity of the process.

The closest to the technical essence of the present invention is a method of obtaining diphenylsulfide by reducing diphenylsulfonic oxide with sulfur at 280 ° C in a nitrogen atmosphere with a yield close to the quantitative G5.

However, carrying out the process at a high temperature and in a nitrogen atmosphere complicates the process and prevents its industrial use.

The purpose of the invention is to simplify the process.

The goal is achieved

10 in that the process of obtaining diphenylsulfide by reducing sulfur diphenylsulfoxide by heating is carried out in the presence of thionyl chloride or sulfur dichloride in an amount of 0.115 0.2 mol per mole of the starting diphenylsulfoxide at 110-120 ° C as a catalyst.

The yield of the target product is 95-98%.

Example 1. In a 1 liter reaction vessel equipped with a stirrer, a thermometer and a reflux condenser, connected at the outlet to the dropping funnel, a venting tube (to remove the evolved gas in the absorption vessel) and a liquid gate connected to the reaction flask, 404 , 6 g (2 mol) of diphenyl sulfoxide, 29.0 g (0.9 mol) of sulfur. The mixture is heated at 110 ° C until sulfur is completely dissolved.

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then cooled to 75-70 ° C and at this temperature 48 g (0.4 mol) of thionyl chloride are introduced within 1 hour. After this, the temperature is gradually increased to 110-120 C (so that there is no too intensive foaming) and withstand at this temperature for 1 hour until complete absence of diphenylsulfoxide.

The control of the end of the reduction process is carried out by thin layer chromatography.

After completion of the reduction process, the reflux condenser is replaced with a direct cooler and the catalyst is distilled off, the reaction mass is cooled to. To remove the sulfur impurity, 50 ml of water, 50 ml of concentrated hydrochloric acid, and 10 g of zinc are added and heated until the zinc is completely dissolved at 100 ° C. In this case, the color of the reaction mass varies from greenish to pale yellow. The mixture is cooled to room temperature, the salt layer is separated, the target product is washed with water from salt impurities and dried at a residual pressure of 0.20, 3 MPa. The yield of technical diphenylsulfide is 365 g (98%), the content of the basic substance is 99.5%. If necessary, the product is subjected to vacuum distillation under known conditions, the yield is 355 g (95%).

Example 2. The process is carried out as in Example 1, but the catalyst (thionyl chloride) is introduced in an amount of 24 g (0.2 mol).

The yield of technical product is 355 g (95%), the content of the main substance is 99.2%,

Example 3. The process is carried out as. in Example 1, but the catalyst (thionyl chloride) was introduced in an amount of 36 g (0.3 mol).

The yield of technical product is 359 g (96%), the content of the basic substance is 99.3%.

Example 4. A setup for carrying out the reaction is described in Example 1. 404.6 g are placed in a reaction flask.

(2 mol) diphenyl sulfoxide, 29.4 g (0.7 mol) sulfur. The mixture is heated at 110 ° C until the sulfur is completely dissolved, then cooled to 70-75 ° C and 41.2 g (0.4 mol) of sulfur dichloride are introduced at this temperature for 1 hour. After that, the temperature is gradually increased to 120 ° C (so as not to overstretch D too intensively and maintain at this temperature until complete absence of diphenyl sulfoxide (about 1.5 hours). The control of the end of the process is carried out by thin layer chromatography. The technical product is purified from sulfur as described in Example 1.

The output of the technical final sulfide is 360.0 g (96%), the content of the basic substance is 99.3%.

The proposed method allows to simplify the process by reducing the temperature from 280 to 110-120 ° C and eliminate the use of an inert gas atmosphere, since special equipment is not required.

Claims (2)

Invention Formula The method of obtaining diphenylsulfide by reducing diphenylsulfoxide with sulfur when heated, characterized in that, in order to simplify the process, the latter is carried out in the presence of thionyl chloride or sulfur dichloride in an amount of 0.1-0.2 mol per mole 5 of the starting diphenylsulfoxide at 110-120С . Sources of information taken into account in the examination 0 1. Weigand-Hilgetag. Experimental methods in organic chemistry. M., Himi, 1968, p. 579. 2. RZHH. 1976, 20, F 80. Z.RJH. 1961.13 Zh157. 5 4. USSR author's certificate No. 431769, cl. C 07 C 149 / 30,28.07.72. 5. RZHH. 1964, 8 F 62 (prototype)