SU1168559A1 - Method of obtaining 2-alkylamino-2-thiazolines - Google Patents

Abstract

METHOD OF OBTAINING 2-ALKILAMINO-2-TIAZOLINES of the general formula and “HRl where R. is isopropyl, sec-butyl or cyclohexyl; RJ is independently of each other hydrogen, methyl or phenyl, characterized in that, in order to increase the yield and expand the range of target products, the corresponding 2-amino-2-thiazoline is reacted with the corresponding irotic alcohol in a 70-90% sulfuric medium. kis (L lots at 45-95 S. with

Description

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The invention relates to organic chemistry, namely to a method for producing 2-alkylamino-2-thiazolino which are used in the synthesis of biologically active compounds. The purpose of the invention is to increase the yield of the target product, as well as to expand the range of targeted products. Example 1. Sinte 2-isopropylamino-2-thiazoline. 0.05 g-mol (5.1 g) of 2-amino-2-t zolin is dissolved in 50 ml of sulfuric acid and heated to the reaction temperature, with vigorous stirring 0.075 g-mol (4.5 g , 5.7 ml) of anhydrous isopropyl alcohol. The resulting mixture was incubated for 3 hours, then cooled and poured onto a mixture of ice and water (200 g). The sulphate solution is neutralized while cooling with an aqueous solution of ammonia (25%). The crystals that separated were filtered out, washed with water and dried. In tab. 1 presents data on the yield of the product. As follows from the table. 1, the optimal conditions are the reaction temperature and the sulfuric acid concentration of 85%. The yield is 71% (5.2 g), m.p. 106-107 ° C. Found,%: N 19.67; S 22.16. Calculated,%: N 19.42; 822.23. Example 2. Synthesis of 2-sec-butylamino-2-thiazoline. 0.05 gmol (5.1 g) of 2-amino-2-zol is dissolved in 50 ml of sulfuric acid and heated to reaction temperature, with vigorous stirring introduced from a dropping funnel; 5.6 g-mol (7 ml) sec-butyl alcohol. The resulting mixture is kept under the specified conditions for 3 hours, cooled poured onto a mixture of ice and water (200 sulphate solution is neutralized upon cooling with an aqueous solution of ammonia (25%). The thick, thick oil is extracted with benzene (3x30) and dried with potassium hydroxide. After distillation of benzene, the product cereal under vacuum. Data on the yield of the product are shown in Table 2. A colorless oil is obtained with boiling point; 101-102s / 2 mm Hg. After standing, the oil crystallizes into colorless needles with mp 98-99 seconds. (petroleum ether.) Found,%: N 17.78; S 20.30. C ,, S Calculated,%: NS 20.25. As follows from Table 2, the optimal conditions are 80 ° C and an acid concentration of 85%. Example 3. Synthesis of 2-cyclohexylamino-2-thiazoline 0.05 gmol (5.1 g) 2-amino-2-thiazoline dissolved in 50 ml of sulfuric acid and 0.075 g-mol (10 g, 10.16 ml) of cyclohexyl alcohol are introduced at heating to the reaction temperature. The product is processed as in Example 1. The yield of the product is shown in Table 3. The most optimal conditions are M are the reaction temperature, the concentration of sulfuric acid. 85%. Yield 89% (8.2 g). M.p. , 5 ° C (hexane). Found,%: N l5.20; S 17.3. . . Calculated,%: N 51.31; S 17.39. Example 4. Synthesis of 2-isopropylamino-2-thiazoline. 0.05 gmol of 2-amino-2-thiazoline is dissolved in 50 ml of sulfuric acid. Conditions for processing and processing are similar to example 1. Data on the yield of the product are presented in Table. 4. Optimum conditions — reaction temperature 80 ° C, acid concentration 85%. Output 87% (7 g), so pl. 10A-1Q5 C (water). Found,%: N 17.51; S 20.18 ,, N, S Calculated,%: N 17.70; S 20.25. Example 5. Synthesis of 2-in op-butylamino-5-methyl-2-thiazoline. 0.05 g-mol (5.8 g) of 2-amino-5-methyl-2-thiazoline is dissolved in 50 ml of sulfuric acid (conditions as in example 2) and, when heated to the reaction temperature, 0.075 g are introduced with vigorous stirring -mole (5.6 g, 7 ml) sec-butyl spirtach The data on the yield are presented in table. 5. Optimum conditions — reaction temperature, acid concentration 85%. The output of 6.3 g (73%), so pl. 112lieC / S mmr.st .. After one hundred minutes, the product crystallizes with so pl. 67-68 C (petroleum ether). Found,%: N 16.36; S 18,52. C “H, jN, S Calculated,%: N 16.26; S 18.61. Example 6. Synthesis of 2-cyclohexylamino-5-metsh1-2-thiazoline. 0.05 gmol (5.8 g) of 2-amino-5-metsh1-2-thiazoline is dissolved in 50 ml of sulfuric acid, the solution is heated to the reaction temperature and with vigorous stirring 0.075 g-mol (10 g , 10.6 ml) of cyclohexyl alcohol. The mixture is processed as in example 1. The output data are presented in table. 6. Yield 7 g (71%), so pl. 107 107, 5С (hexane). Found,%: N 13.88; S 16.00. N38 Calculated,%: N 14.13; S 16.16. Example 7. Synthesis of 2-cyclograle-5,5-dimethyl-2-thiazoline.

Table 594 0.05 g-mol (6.5 g) of 2-amino-5,5-dimethyl-2-thiazoline is dissolved in 50 ml of sulfuric acid and, with vigorous stirring, 0.075 g-mol (10 g, 10 , 6 ml) of cyclohexyl alcohol (the reaction conditions are the same as the example). Data on the output are presented in table. 7. The yield of 7.9 g (75%), so pl. 156157С (hexane). Found,%: N 13.4; S 15.64. Calculated,%: N 13.9; S 15.57. Example 8. Synthesis of 2-cyclohe1: power-5-fensh1-2-thiazoline. 0.05 g-mol (8.9 g) of 2-amino-5-phenyl-2-thiazoline is dissolved in 50 ml of sulfuric acid, the solution is heated and 0.075 (10 g, 10.6 ml) of cyclohexyl acid is added with vigorous stirring. alcohol (reaction conditions are similar to example 1). The yield data are presented in table, - 8. The yield is 82.5%, so pl. H7 ° C (octane) Na1dodeno,%: N 11.00; S 12.25. Q; ri ,, N, s Calculated,%: N 10.76; S 12.33.

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Claims (1)

METHOD FOR PRODUCING 2-ALKYLAMINO-2-THIAZOLINES of the general formula wherein - isopropyl, sec-butyl or cyclohexyl; R, is independently hydrogen, methyl or phenyl, characterized in that, in order to increase the yield and expand the assortment of target products, the corresponding 2-amino-2-thiaeolin is reacted with the corresponding secondary alcohol in 70-90% medium sulfuric acid at 45-95 C. SU ..... 1168559> 1 1168559 2