SU121791A1 - The method of obtaining 1, 2, 4-trithiolanes - Google Patents

Description

A method is proposed for the preparation of aliphatically substituted 1, 2, 4-trithiolanes not previously described in the literature by reacting aliphatic aldehydes or ketones with hydrogen sulfide and sulfur at O-10 ° in the presence of ammonia or amines, primary or secondary.

The reaction proceeds according to the scheme (for example, butanone):

NzSNHSS / S X ..SN,

2.) cO + S4-2HoS- / CC; С (HsC, / - Н-, СХ S-S / С, Нз

The process is recommended by adding hydrogen sulphide to a mixture of two moles of aliphatic aldehyde or ketone and 1-2 moles of amine or 0 ° and adding 1-2 g of sulfur in portions. The use of smaller amounts of amine in some cases leads to a decrease in yield. On the other hand, the use of significant quantities of amine is not reflected noticeably on the product cost, since amines can be regenerated quantitatively. When using ammonia as a catalyst, it is advisable to introduce ammonia and hydrogen sulfide in a 1: 1 volume ratio into the aldehyde or ketone and add sulfur in small portions.

1, 2, 4-trithiolanes differ from other compounds also containing three sulfur atoms, for example, from trisulfides or tritions with the ability to react with primary amines to form hydrogen sulfide and sulfur amines.

Aliphatic substituted 1, 2, 4-trithiolanes obtained by the proposed method can be used to combat agricultural pests, to destroy weeds, as anticorrosive agents and vulcanization accelerators.

 121791-2 -

Example 1. In a mixture of 172 g of diethyl ketone and 146 g of isobutylamine, hydrogen sulfide is introduced at 0 ° with good stirring. When this occurs, the fine amine sulfhydrate precipitates, and the mixture thickens. At the end of the increase in hydrogen sulfide, 64 g of sulfur is added in portions. Continuing stirring, continue for several hours to permeate a weak current of hydrogen sulfide. In this case, sulfur dissolves completely. Dilute acetic acid is added to the reaction mixture in excess, due to which amine sulfhydrate decomposes to produce hydrogen sulfide and sulfur. You can regenerate 25 g of sulfur. The trithiolane present in the lower layer together with sulfur is extracted with ether. The extract is washed several times with water and once with sodium bicarbonate solution and dissolved in sodium sulfate and after distillation, the ether is distilled in vacuo. At the same time, 3, 3, 5, 5-tetraethyl-1, 2, 4-trithiolane is distilled at 84 ° (0.2 mm Hg) as an orange oil. The yield is 192 g, or 81% of the theoretical.

After adding caustic soda, the amine is regenerated from the acetic acid solution in the usual way, almost quantitatively.

Example 2. A mixture of 196 g of cyclohexanone and 146 g of m-butylamine is saturated with hydrogen sulfide under continuous stirring at 0 °, after which 32 g of sulfur are added. Upon further stirring and introducing hydrogen sulfide, after approximately two hours, the crystalline product of the reaction begins to precipitate. The reaction mixture is stirred without cooling for a long time, for example, in the continuation of the night, and hydrogen sulfide is slowly passed through it. In this case, sulfur quantitatively reacts. Granular tritiolane, suspended in liquid amine sulfhydrate, is sucked off, washed several times with cooled to 0 ° methanol to an almost colorless filtrate and recrystallized from a large amount of ethanol. Already after a single recrystallization, white, friable crystalline scales with m.p. 50 °. The output of bis-3,3, 5,5-pentamethylene-1, 2, 4-trithiolane - 215 g, or 83% of the theoretical.

Example 3. In a one-liter flask, a mixture of 116 g of acetone and 206 g of diisobutylamine is cooled to 0 °. With the stirring of the latter, hydrogen sulfide is introduced into the gas space above the liquid under slight pressure. (It is not advisable to inject hydrogen sulfide into the liquid, since, due to the release of crystalline amine sulfhydrate, the pipe quickly clogs.). The mixture, saturated with hydrogen sulfide, thickens strongly. Continuing to mix, add 32 g of sulfur in portions. At the same time, the mass is colored brown and becomes much more mobile. After some time, it thickens again, but it can still be mixed. Continuing to introduce hydrogen sulfide, the mass is stirred overnight without cooling. The resulting almost colorless, relatively mobile mass is acidified, the organic layer is separated and washed with water and bicarbonate solution. After drying with sodium sulfate and distillation in vacuo, light yellow 3, 3.5, 5-tetramethyl-1, 2, 4-trithiolane is obtained. T. Kip. 34 ° (0.4 mm Hg). The yield is 80.4 g, or 44% of the theoretical.

From the solidified residue after distillation, solid white duploditioacetone in the amount of 23.5 g is isolated.

Example 4. 206 g of diisobutylamine are saturated at 0 ° with hydrogen sulfide. This releases crystalline amine sulfhydrate. Continuing the stirring and addition of hydrogen sulfide, 116 g of propionaldehyde is added dropwise at a temperature not higher than 10 °. Then, at 0 °, 32 g of sulfur is added in portions. The mass gradually turns yellow first, then brown. The transmission of hydrogen sulfide and mixing continue for another 24 hours. The reaction product is isolated.