SU455107A1 - The method of obtaining rhodanine-4-thion-3alkylcarboxylic acids - Google Patents

Description

The invention relates to a process for the preparation of rodanin-4thion-3-alkylcarboxylic acids not previously described in the literature, which are intermediate products in the synthesis of physiologically active substances.

The reaction of amides with piscerous phosphorus with the formation of the corresponding thio analogs is known.

According to the present invention, the described method is based on the known reaction of producing rhodanine-4-thion-3-alkylcarboxylic acids, water-soluble derivatives of rhodanine-4-thione, with the interaction of rhodamine-3alkylcarboxylic acids with phosphorus phosphorus, preferably at a reagent ratio of 3: 1.

The reaction is carried out in dioxane at the boiling point of the latter.

Example 1. Rodanin-4-thion-3-acetic acid.

5.74 g (0.03 mol) of rhodanine-3-acetic acid B is dissolved in 45 ml of dry freshly distilled dioxane and 2.3 g (0.01 mol) of phosphorous phosphorus are added. The reaction mixture is heated to reflux with vigorous stirring for 1.5 hours. Activated carbon was added to the resulting solution, boiled for about 5 minutes and filtered. From the filtrate after distillation of dioxane in a water bath in a small m.

vacuum. I get a yellow oily substance. The output of 4.8 g (77% of theoretical).

Rodanin-4-thiop-3-acetic acid, obtained by the above described method. shaken with 50 ml of water) 1 extracted with 250 ml of diethyl ether; Effpr-dioxaic solution was dried without water; 1N: 1m sodium sulfate. After the ether and dioxane are distilled off in a water bath under a slight vacuum, a yellow, slightly similar substance is obtained, which cannot be dispersed in a vacuum (0.01 mm Hg). Yield 4.2 g (67.5%).

Paydeno,%; N 6.65; S 46.07.

CsHsO.NSa.

Calculated,%; N 6.75; S 46.40.

Condensation with rhodan P-4-thion-3-acetic acid was carried out for condensation with l-chlorobenzaldehyde to obtain rhodanine-5 - " chlorobenzylidene-4-thione-3-acetic acid.

7.5 ml of dioxane solution. contains 0.005 mol of 4-thion-rhodamine-3-acetic acid, mixed with 0.005 mol of n-chlorobenzaldehyde with 5 ml of glacial acetic acid and 0.5 g of fused acetic sodium. The reaction mixture is heated for 60 minutes, diluted with 100 ml of water, filtered; yield 1.35 g (82%). Crystallization from ethanol gives a red-orange product with mp. 254-255 ° C

Found,%; K 4.19; S 28.78.

CisngOsNSaCl.

Calculated,%; N 4.24; S 29, G6.

Example 2. Rodanin-4-thion-3-e-1 ag1-rioic acid.

7.42 g (0.03 mol) of rhodanine-Z-e-caproic acid is dissolved in 35 ml of dry, freshly distilled dioxane and 2.3 g (0.01 mol) of phosphorous phosphorus are added. The mixture is boiled under intensive stirring for 1.5 hours and 3 minutes with activated carbon and filtered. The filtrate was shaken with 50 ml of water and extracted with 250 ml of diethyl ether. The ether dioxane solution was dried over anhydrous sodium sulfate. After distilling off the ether and dioxane in a water bath under a slight vacuum, a yellow oily substance is obtained. The output of 4.35 g (55% f from theoretical). During vacuum distillation (0.01 mmHg), the product darkens and does not accelerate.

Found,%: N 5.29; S 36.21.

С9Н1зО2К5з.

Calculated,%: N 5.31; S 36,52.

Example 3. Rodanin-4-thion-3-p-propionic acid, 2.05 g (0.01 mol) of rhodanine-3-propionic acid was dissolved in 25 ml of dry freshly distilled dioxane and boiled with 0.8 g ( 0,0033 mol) n-grained phosphorus for 1 hour. The resulting clear, light orange solution was boiled over an ech for 3 minutes with activated charcoal and filtered. The filtrate is shaken with 30 ml of water and extracted with 200 ml of diethyl ether. The ether dioxaic solution is dried with anhydrous sodium sulfate and the solvents are distilled off in a water bath, under a slight vacuum. A yellow-orange oily substance is obtained which is not accelerated in vacuum (0.01 mm Hg). The output of 1.82 g (82.2%).

Found,% :: N 6.17; S 43.37.

C6H702NS3.

Calculated,%: N 6.33; S 43.47.

5-ha-Chlorobenzylidene-4-thionrodanine-3-p-propionic acid is prepared according to the procedure described above to produce rhodanine-5-p-chlorobenzylidene-4-thion-3-acetic acid. Yield 1.1 g (65%;). Crystallization from methanol yields a yellow-orange product with m. Il. 220222 ° С

Found,%: N4.01; S 27.69.

CisHioOaNSsCl.

Calculated,%; N 4.07; S 27.97.

P 11 e d emetra t

Claims (2)

1. A method for producing rhodanine-4-thion-3-alkylcarboxylic acids, characterized in that rhodanine-3-alkylcarboxylic acids are reacted with phosphorus pentahedral in dioxane by heating, followed by isolation of the target product by known techniques. 2. A method according to claim 1, characterized in that the reactants are taken in a molar ratio of 3: 1.