SU997608A3 - Process for preparing derivatives of 2,3-dicyanopyrazine - Google Patents

Description

cyano, oxy or alkoxy, where alkyl with 1–3 carbon atoms, carboxy, ethoxycarbonyl, alkanoyl with 1–3 carbon atoms, diethylamino, phenyl or tolyl; allyl, cyclohexyl, unsubstituted phenyl or substituted by one or two substituents from the number of halo, trifluoromethyl, alkyl with 1-3 carbon atoms or alkoxy with 1-3 carbon atoms; or R and R2 together with a common nitrogen atom form a 3-7 membered nitrogen-containing cycle, or morpholine, 2, 3-dicyano-5-halopyrazine of the general formula 11 Yi where A has the indicated values, and X is a halo, is subjected to interaction with the compound formulas W, HB where B has the indicated values. The reaction is usually carried out in an inert solvent of, number of ketones, such as acetone, methyl isobuty, ketone; ethers such as tetrahydrofuran, dioxane; esters such as ethyl acetate, butylacetate chlorinated hydrocarbons such as chloroform, trichlorethylene, hydrocarbons such as hexane, heptane, benzene, toluene. It is preferable to use acetone, tetrahydrofuran diox. T or benzene in an amount of 1-100 parts by weight. on the starting compounds of the scientific research institute of formula 11, preferably 2050 parts by weight The reaction can be carried out in homogeneous or heterogeneous systems using a mixture of water and organic Koro solvent. The TeivmepaTypa reaction is not critical and may vary widely depending on the type of reagent used. Usually, the temperature is used below, but it is possible to carry out the reaction at room temperature and lower. The amount of the compound of formula 111 is not limited and can vary over a wide range, usually 1-2 mol, preferably up to 1.5 mol per 1 small compound of formula 11. An equivalent or slightly larger amount (preferably up to 2 eq.) Is used as a hydrogen halide acceptor. an organic base such as pyridine or a tertiary amine (e.g., triethylamine or N, N-dimethylformamide), or an inorganic base such as an alkali metal hydroxide (e.g., sodium hydroxide), or a carbonaceous carbonate (e.g. sodium carbonate). When the compound of formula III is an amine, it can also function as an acceptor of hydrogen halide when such a compound is used in an amount equal to at least 2 mol / mol of the compound of formula i. Example 1. Preparation of 2,3-dicyano-5-chloropyrazine. 7.30 g (0.5 mol) of 2,3-dicyano-5-hydroxypyrazine is dissolved in 70 g (0.59 mol) of thionyl chloride and the resulting solution is cooled to. While stirring, 4.80 g (0.06 mol) of pyridine was added dropwise to this mixture for 15 minutes. The mixture is then stirred at 70 ° C for 2 hours. After completion of the reaction, the excess thionyl chloride is distilled off under reduced pressure, and the residue is extracted with 150 ml of chloroform / ha. The chloroform solution is washed twice with 50 ml of water and dried with anhydrous chlorine. The mixture is distilled off, after which the solvent is distilled off, a red solid is formed. By recrystallization of the substance from benzene, 6.30 g (yield 77%) of 2,3-dicyano-5-chloropyrazine, m.p. 89-900С. Calculated,%: C 43.79; K 0.61; N 34.05. Found,%: С.43,75; And O, 61; N 34.13. Example 2. Preparation of 2,3-dicyano-5-chloro-6-n-pentylpyrazine. Ethyl n-hexanoate and diethyl oxalate are subjected to a Clisen condensation and then hydrolyzed to give 2-oxo-n-hexanoic acid. The product obtained is condensed with diaminomeleonitrile, 9.1 g (0.042 mol) of 2,2-dicyano-5-hydroxy-6-n-pentylpyrazine are obtained (mp. 61-64 ° C). This product was dissolved in 120 g of phosphorus oxychloride and 3.32 g (0.042 mol) of pyridine was added. The mixture was boiled for 5 hours and worked up as in Example 1 ,. the resulting oily product is concentrated under reduced pressure, and then chromatographed on a silica gel column using benzene as the eluent. 1 6.0 g (61% yield) of 2,3-dicyano-5-chloro-6- is obtained. n-pentylpyrazine as a yellow liquid. . Calculated,%: C 56.3; H 4.73; N 23.87. C.H./1N4 Found,%: C 56.57; H 4.60; N 23.52. Example 3. Getting 2, H- isicano-5-chloro-6-phenylpyrazine. Synthesis of 2,3-dicyano-5-hydroxy-6-phenylpyrazine. 5.40 g (0.05 mol) of diamine and nitrile a and 7.50 g (0.05 tb) of bekoyl formic acid were added to 50 np of 2N hydrochloric acid. The mixture is stirred at 20–30 ° C for 30 minutes and then at 70–80 ° C for 2 hours. The mixture is stirred at room temperature. The precipitate formed is separated by filtration, the mixture is poured twice with 4 ml of water, dried in a vacuum. 10.0 g (yield 90%) of 2,3-dicyano-5-hydroxy-b-phenylpyrazine are obtained, m.p. 221-223 with (decomp.). Calculated,%: C 64.86; H 2.72j. By 25.21. a, HeN40 Found,%: C 65.02; H 2.54; N 25.20. Synthesis of 2, 3-dicyano-5-chloro-b-feni pyrazine. 7.00 g (0.0315 mol) of 2,3-dicyano-5-hydroxy-6-phenylpyrazine is dissolved in 40.00 g (0.26 mol) of phosphorus oxychloride and while cooling the solution d is added dropwise in 20 minutes 3, g (0.035 mol) of triethylenin. The mixture was stirred at 70-8 ° C. 1.5. The reaction mixture was worked up as in Example 1. By recrystallization from benzene, 6.10 g (yield: 80%) of 2,3-dicyano-5-chloro-6-phenylpyrazine were obtained with mp 139- 141 C. Calculated,%: C 59.89; H 2.09; N 23.28. C H5N4C1 NO,%: C 59.80; H 2.20; N 23.41. Example 4. Preparation of 2,3-di cyano-5-chloro-6- (m-chlorophenyl) pyrazine 25.07 g (0.10 mol) 2,3-dicyano-5-oxy-6- (m-chlorophenyl) pyrazine is dissolved in 46.2 g (0.30 mol), phosphorus oxychloride. The resulting mixture is cooled to 0-5 ° C and 10.1 g (0.1 mol) of triethylamine are added with stirring to the droplets in 30 minutes. After the addition, the mixture is boiled for 3 hours. The reaction mixture is worked up. to the procedure of Example 1. Petroleum ether (50 ml) was added to the resulting oily product and the resulting precipitate was separated by filtration. By recrystallization from tetrachloric carbon, 23.1 g (yield 83%) of 2,3-dicyano-5-chloro-6- (m-chloro-phenyl) pyrazine with mp. 87-88j. Calculated,% C 52.39; H 1.47; N 20.37. Found,%: C 52.38; H 1.61; N 20.24. Example 5. Preparation of 2,3-dicyano-5- (p-methylphenoxy) pyrazine on. v, 83 g (0.005 mol) of 2,3-dicyano-5-chloropyrazine was dissolved in 25 ml of acetone. The solution is cooled before and with stirring, a solution prepared by mixing 0.54 g (0.005 m) of p-cresol, 0.21 g (0.005 mol) of sodium hydroxide, 1 ml of water and 15 ml of acetone is added dropwise for 15 minutes. The resulting mixture was stirred at 1 h. After completion of the reaction, the solvent was removed by distillation under reduced pressure. The resulting residue is extracted with 100 ml of chloroform. The chloroform solution is washed with 30 ml of IN aqueous solution of sodium hydroxide and 30 ml of water and dried with anhydrous calcium chloride. Then the solvent is distilled off. By recrystallization of the product from ethanol, 0.49 g (yield 41%) of 2, 3-Dicyano-5- (p-methylphenoxy) pyrazine was obtained with a mp. 126-127 ° C. Calculated,%: C 66.10; H 3.41; N 23.72. C HgN40 Found,%: C 66.03; H 3.40; N 23.55. Example 6. Obtaining 2,3-dicyano-5- (phenylthio) pyrazine. 0.83 g (0.005 mol) of 2,3-dicyano-5-chloropyrazine is dissolved in 25 ml of acetone. The solution is cooled to 0-5 ° C and while stirring, a mixture of 0.55 g (0.005 mol) of thiophenol, 0.21 g (0.005 mol) of sodium hydroxide, 1 ml of water and 20 ml of acetone is added dropwise for 10 minutes. Then the reaction mixture is treated by the method of Example 5 and recrystallization from benzene gives 0.57 g (yield 48%) of 2,3-dicyano-5- {phenylthio) pyrazine with mp. 109-112 ° C. Calculated,%: C 69.49; H 2.54; N 23.52. Found,% C 60.60; H 2.43; N 23.71. Example 7 Preparation of 2, 3-dicyano-5- (carboxymethylthio) pyrazine. Thioglycolic acid (92%, 0.01 mol) and 1.64 g of 2, 3-dicyano-5-chloropyrazine (0.01 mol) are dissolved in 40 MP of acetone and added dropwise to 0-5 s while cooling the solution to 0-5 s. 2.12 g (0.021 mol) of triethylamine. The mixture is then stirred at 20-25 seconds for 2 hours. The resulting precipitate is separated by filtration, the filtrate is concentrated under reduced pressure and 100 ml of 1% hydrochloric acid is added, the oily product is extracted with 50 ml of ethyl acetate. The ethyl acetate layer is transferred twice a day with 50 ml of a saturated aqueous solution of sodium chlorine, dried with anhydrous sodium sulfate, and concentrated under reduced pressure. The overcrossing residue from the toluene is 1.65 g (75% yield) of 2, 3-dicyano-5- (carboxypetylthio) pyrazine, mp 141-143 ° C. Calculated,%: C 43.63; H 1.83; N 25.44. Found,%: C 43.60; H 1.85, N 25.38. Example 8. Getting 2, 3-di cyano-5 -phenoxy-6-n-propyl pyrazine. 0.207 g (0.001 mol) of 2,3-dicyaio-5-chloro-b-n-propylpyrazine solution in 15 ml of acetone and a mixture of 0.094 g (0.001 mol) of phenol, 0.040 g (0.001 mol) of sodium hydroxide, 0.7 MP of water and 5. ml of acetone drop by drop for 5 minutes. The mixture is then stirred at 5-10 ° C for 10 minutes. The reaction mixture is treated by the method of Example 7 and the residue is recrystallized from benzene. Obtain 0.15 g (yield 57%) of 2,3-dicyano-5-phenoxy-6-propylpyrazine with m.p. 130-132C. Calculated,%: C 68.17; H 4.58; N 21.20. q, S Found,%: C 68.27; H 4.50; N 21.42. Example 9. Preparation of 2, 3-di cyano-5-ethylthio-6-methy lpirazine a. 1.79 g (0.01 mol) of 2,3-dicyano-5-chloro-6-methylpyrazine, 0.62 g (0.001 mol) of ethanethiol and 0.40 g (0.01 mol) of sodium hydroxide are treated by the method of example 6. Per crystallization from ethanol, 0.91 g (yield 45%) of 2, 3-Dicyano-5-ethylthio-6-methylpyrazine, m.p. 91.5-92 ,. Calculated,%: C, 52.98; H 3.95; A / 27.43. Found,%: C 52.74; H 3.88; 27.61. Example 10. Preparation 2, 3-d cyano-5-ally l hydroxy-6-ethylpyrazine a. 1.35 g (0.07 mol) of 2,3-dicyano-5-chloro-6-ethylpyrazine is dissolved in 30 ml and while cooling the solution, a solution obtained from 20 ml of allyl alcohol and 0.16 g is added dropwise. (0.007 mol sodium) - The mixture is then stirred for 30 minutes. The reaction mixture is poured into 200 ml of water and the oily product separated off is extracted with toluene. The toluene layer is concentrated under reduced pressure. The resulting crude product is chromatographed on a silica gel column. using toluene as eluent. 1.00 g (yield 67%) 2.3-11, are obtained, cyano- 5-apyloxy-6-ethylpyrazine, p 1.5316. Calculated,%: C 61.67; H 4.71; N 26.15. C H. O Found,%: C 61.46; H 4.83; N 26.01. According to the procedures of Examples 5-10, compounds W 1-30, 44-53, 71, 72, 82-88, 95, 97-99, 103, 105 and 112-130 are synthesized as shown in Table 1, Example 11: Preparation of 2, 3-dicyano-5-di-n-propylamino-6-ethyl pyrazine 1.92 g (0.01 mol) of 2,3-dicyano-5-chloro-b-ethyl pyrazine dissolved in 30 ml acetone, cooled to 0-5P C, and with stirring, g (0.02 mol) of di-n-propylamine is added dropwise to it. The mixture was stirred for 30 minutes. The precipitate is separated by filtration. The filtrate is concentrated under reduced pressure to give a yellow oily product. Water was added to the oily product (20 ml), and a white powder was recrystallized from ethanol. Get if 28 g (yield 50%) of 2, 3-dicyano-5-di-n-propylamino-6-ethylpyrazine with so pl. 58-60C. Calculated,%: C 65.34; H 7.44; N 27.21. Found,%: C 65.15; H 7.48; N 27.36. Example 12. Getting 2, 3-dicyano-5-methyl amino-6-n-butylpyrazine. 2.21 g (0.01 mol) of 2, 3-dicyano-5-chloro-6-H-butylpyrazine are dissolved in 30 ml of benzene and with stirring, 1.55 g (0.02 mol) of 40% - is added with stirring. methylamine solution. The mixture is then stirred at 30-40 ° C for 2 hours. The reaction mixture is worked up by the method of Example 13. 1.75 g (yield 81%) of 2, 3-dicyano-5 -methyl methane-6-n-butylpyrazine is obtained. from m.p. 143-145p. Calculated,%: C, 61.38; H 6.09; N 32.54. , “, Nr Found,%: C 61.60; H 6.12; N 32.28. Example 13. Preparation of 2, 3-dicyano-5-n-propylamino-6-zobut ilpyrazine. 1.10 g (0.005 mol) of 2,3-dicyano. 5-chloro-6-isobutylpyrazine is dissolved in 20 ml of tetrahydrofuran. The resulting solution was treated as in Example 11, using 0.30 g (0.005 mol) of n-propylamine and 0.02 g (0.005 mol) of sodium hydroxide. Obtain 1.04 g (yield 85%) of 2,3-dicyano-5-n-propylamino-6-from. Butylpyrazine with so pl. 107-110 s.

Calculated,%: C 64.17} H 7.04; N 28.78.

(SN | 7

Found,%: C 64.13; H 7.24;

N 28.63,

Example 14. Obtaining 2,3-dicyano-5-diztilamino-6-benylpyrazine

1.27 g (0.005 mol), 2,3-dicyano-5-chloro-b-benzylpyrazine is dissolved in 30 MP of benzene and the resulting solution is cooled to. With stirring, the mixture is treated in the same manner as in Example 13 using 0.80 g (0.01 mol) diethylamine.

Recrystallization from ethanol yields 1.10 g (75% yield) of 2,3-dicyano-5-dethylamino-6-benzine 1 pyrazine, m.p. 73-74C ..

Calculated,%: C, 70.08; H 5.88 24.04.

, 7М5

Found,% C 70.30; H 5.75;

At 23.95.

According to the procedures of the examples, compounds Nos. 31-43, 54-70, 73-81, 89-94, 96, 100-102, 104, and 106-111 are shown in; tab. one.

Example 15o Preparation of 2,3-dicyano-5-n-propylamino-6-phenylpyrazine.

12.03 g (0.05 mol of 2,3-dicyano-5-chloro-6-phenylarazine is dissolved in 400 ml of toluene. The solution is cooled before and under stirring, 3.25 g (0.055 mol) is added dropwise in 10 minutes n-propylamine. After this, 55 ml of 1N aqueous solution of sodium hydroxide are added dropwise in 10 minutes. The mixture is then stirred at 5-10 s 30 min. After the reaction has completed, the reaction mixture is divided into two layers. The toluene layer is concentrated under reduced pressure and a solid is obtained which is washed twice with 200 ml of water, dried under reduced pressure and subsequently recrystallized yvayut of topu ol in ethanol.

12.1 g (92% yield) of 2,3-dicyano-5-n-propylamio-6-phenylpyra aeia are obtained with a mp. 136-137®C.

Calculated,%: C-68.43;) And 4.38 V26.60:

1.N "MchFound,% C 68.42; H 5.01; 26,58.X.

Ex. 16. Preparation of 2,3-dicyano-5-ethylamino-6-phenylpyrazine. I 12.03 t (0.05 mol) - 2,3-dsdaano-5-zchor-6-phenylpyrazine and 7.07 g (0.11 mol) of a 70% aqueous solution of ethylamine are treated by the method of Example 11 and recrystallized from toluene.

10.98 g (88% yield) of 2,3-dic1: ano-5-ethyl-amino-6-feiylpyrazine are obtained with m.p. 180-181 ° C.

Calculated,%: C, 67.45; H 4.45; N 28.10.

C ,,

Hl

found%: C 67.51; H, 52; N 27.07.

Example 17. Obtaining 2,3-di cyano-5-ethylamino-6- (m-bromophenyl) pyrazine. .

1.15 g (0.0036 mol) of 2,3-dicyano-5-chloro-6- (m-bromophenyl) pyrazine is dissolved in 20 ml of tetrahydrofuran. The solution is cooled to add 0.50 g of a 70% aqueous solution of ethylamine. The mixture is treated by the method of Example 13 and recrystallized from ethanol.

Obtain 0.95 g (yield 80%) of 2,3-dicyano-5-ethylamino-6- (m-bromophenyl) pyrazine, m.p. 127-127 ,.

Calculated:% 1 C 51.24 H 3.07; M 21.34.

El,%: C 51,55; H 3.04;

N 21.17.

Example 18. The preparation of 2,3-dicyano-5-n-propylamino-6- (m-chlorofen.-nyl) pyrazine. ,

1 gO (0.0036 mol) 2.3-; shchy-5-chloro-6- (m-chlorophenyl) pyrazine 0.24 g (0.004 mol) of n-propylamina and 40 ml of 0.1 N aqueous sodium hydroxide solution are treated as in example 15 and recrystallized from methanol. .

Obtain 0.54 g (yield 78%) of 2,3 -, - dicyano-5-n-propylamino-6- (i / t-xnophenyl) -pyrazine with so pl. 120-121 0,

Calculated,%: C 60.51; H 4.06; N 23.52.

C, H, C.

Found,% g C 60.75; H 4.04; N 23.41.

Example 19. Preparation of 2,3-di. Cyano-5-ethylamino-6- (m-fluorophenyl) pyrazine.

1.00 g (0.0039 mol) of 2,3-dicyano-5-chloro-6-mChfluorophenyl) pyrazine is dissolved in 30 ml of toluene. The resulting solution is cooled before and 0.65 g of a 70% aqueous solution of ethylamine is added dropwise. The mixture is stirred at-5-0 0 Zb min. The reaction mixture is processed by the method of prigler 11 and recrystallized from ethanol ..

This gives 0.63 g (61% yield) of 2,3-dicyano-5-ethylamino-6-m-fluorophenyl pyrazine, m.p. 126-127 C.

Calculated,%: C, 62.91; H 3.77; N 26.21.

C, .RnNrF

,%: C 62.90; H 3.51; N 26.02. Example 20. Obtaining 2,3-di cyano-5-n-propylamino-C-p-tolylpyrazine. 1.00 g {0.0039 mol) 2,3-dicyano-5-chloro-6-p-tolylpyrazine and 0.46 g (0.0076 mol) s-propylamine are treated by the method of example 11 and recrystallized from toluene. Obtain 0.80 g (yield 74%) of 2,3-di, iano-5-n-propylamino-6-p-tolylpyrazine with so pl. 115-116 0. Calculated,%: C 69.29} H 5.45; N 25.25. C-f6% V 1%,%: C 69.02; H 5.00; N, 25.23. According to the procedure described in Examples 15-20, compounds Nos. 131-144, 152, 153, 155-161, 163, 172, 174-179, 181-188, 191-193, 195 212, are obtained. 224 and 225 presented in table. 1. Example 21. Preferred 2,3-dicyano-5- (1-carboxy-n-propyl C1Mino-6-phenylpyrazine. 2.41 g (0.01 mol) of 2,3-di-diano-5-chloro-6-phenylpyrazine dissolved in 30 ml of tetrahydrofuran and a mixture of 2.04-C (0.02 mol) 01-c-amino-n-butyric acid, 1.12-is added dropwise with stirring at 15-20 s for 5 min. g (0.02 mol) of potassium hydroxide and 40 ml of water. Then the mixture is stirred at 30 minutes. After completion of the reaction, the reactor is cooled with ice and 2 ml of concentrated sulfuric acid is added to the reaction solution. Then the solution is extracted with 100 ml of toluene. The toluene layer is washed with 50 ml. About aqueous Bdpa of sodium chloride and 30 ml of water and the solvent is removed by evaporation, under reduced pressure, to obtain a yellowish-white solid. Recrystallization from ethanol gives 2.63 g (36% yield) of 2,3-dicyano-5- (1- carboxy-n-propyl amino-6-phenylpyrazine with m, pl 210-217 C (decomp.). Calculated,%: C 62.53; H 4.26; N 22.72. "NpOi Found,%: C 62.33; H 4.15; N 22.86, Example 22, Preparation of 2,3-d cyano-5- (1-carboxyethyl) amino-6-phenylpyrazine, 4.82 g (0.02 mol) 2, 3-Dicyano-5-chloro-6-phenylpyrazine is dissolved in 50 ml of acetone, cooled to 0 ° -5 ° C and a mixture of 1.78 is added dropwise with 30 mi g (0.02 m6 lv) 1 DL-alanine, 1.64 g (0.02 mol) of sodium hydroxide and 40 ml of water. Then the mixture is treated by the method of example 21 and recrystallized from benzene. 2.46 (yield 4%) of 2,3-dicyano-5- (1-carboxyethyl) amino-6-phenylpyrazine are obtained with m, pl. 200-203С (times,). Calculated,%: C, 61.43; H 3.78; 23.88. C, (L Found,%: C, 61.48; H, 3.84; 23.72. According to the procedures of Examples 21 and 22, compounds Nos. 67, 145151, 154, 162, 173, 180, 189, 190, 194 and 213 are obtained presented in Table 1, Pr and me p 23, Preparation of 2,3-dicyano-5-chloro-6-isopropoxypyrazine, 50 ml of isopropanol is added to 1.99 g (0.01 mol; 2g3-dicyano-5 , 6-dichloropyrazine and the resulting mixture is boiled for 10 hours. After completion of the reaction, isopropanol is distilled off under reduced pressure. The resulting product (1.14 g) is chromatographed on a silica gel column using benzene-n-hexane as an eluent. , 00 g (45% yield) 2, .3-dicyano-5.-Chloro-6-of Propoxypyrazine with m, pl, 48,. Calculated,%: C 48.55; H 3.17; 25, P, C9H-, N40Ce Found,%: C 48.51; H 3.17; N 25.20, Example 24 Preparation of 2,3-dicyano-5-chloro-6-phenoxypyraein, 1.00 g (0.005 mol) of 2,3-dicyano-5, 6-dichloropyrazine is dissolved in 50 ml of tetrahydrofuran and the solution is cooled to (-15 ) - (- 10) C. Then a mixture of 0.47 g (0.005 mol) of phenol, 0.21 g (0.005 mol) of sodium hydroxide and is added. 25 ml of water 30 m to. The mixture is stirred at (-15) - (- 10) 1h. The reaction mixture is then poured into 100 ml of ice-water and the precipitate is separated by filtration, the resulting precipitate is dissolved in 50 ml of chloroform, washed with 20 ml of dilute aqueous sodium hydroxide solution and 3Q ml of water, dried with anhydrous calcium chloride and concentrated under reduced pressure. The crude product is chromatographed on a column containing — 60 g of silica gel using benzene as eluent. Obtain 0.65 g (yield 50% of 2,3-dicyano-5-chloro-b-phenoxypyrazine with mp 115-118 ° C. Calculated,% 5 C 56.16; H 1.36; N 21, 83. C HeNxOCl: Found: C 56.12; H 1.97; N 21.86. Example 25. Preparation of 2,3-diio-5-chloro-6-ethylthiopyravine 1.00, g (0.005 mol ), 2,3-dicyano-5, 6-dachloropyrazine and 0.47 g of ethanethiol are dissolved in 50 ml of another tint. The hatch is cooled to (-15) - (-10) C and a solution is added dropwise in 30 min. 0.40 g (0.005 mol) of pyridine in 40 m of water. The mixture is treated by the method of Example 24. This gives 0.33 g (yield-29%) of 2,3-dicyano-5-chloro-6-ethylthiopyrazine, mp 55, 0-58.5 C. Calculated,%: C 42.77; H 2.24; N 24.94. Cgft-N SCI; Found,% G 42.75; H 2.25; N 24.98. Example 26. Preparation of 2,3-d cyano-5-ethylamino-6-phenoxypyrazine. 2.07 g (0.01 mol) of 2,3-dicyano-5-ethylamino-6-chloropyrazine are dissolved in 40 ml of tetrahydrofuran and dissolved the thief is cooled to, then a mixture of 0.94 g (0.01 mol) nol, 0.56 g (0.01 mol) potassium hydroxide, 5 ml of water and 20 ml of tetrahydrofuran is added dropwise to it with stirring 10 minutes and stirred at 1 h. After completion of the reaction, the precipitate was separated by filtration. The filtrate is concentrated under reduced pressure and the residue is poured into 80 ml of aqueous dilution. The precipitated crystals are separated by filtration and recrystallized from benzene. 2.22 g (yield 84%) of 2,3-dicyano-5-ethylamino-6-phenoxypyrase are obtained with a mp. 197-198 p. Calculated,%: C 63.89; H 4.18; N 26.40. Found,%: C 63.40; H 4.08; N 26.40. According to the procedure described in Example 26, compounds 216-220 were synthesized as shown in Table 1. Example 27. Preparation of 2,3-dicyano-5-n-propylamino-6- (benzothio) pyrazine. 1.11 g (0.005 mol) of 2,3-dicyano-6-n-propylamino-6-chloropyrazine and 0.87 g (0.007 mol) of benzylthiol are dissolved in 50 ml of acetone. The solution is cooled to. While stirring for 30 minutes, a mixture of 0.40 g (0.005 mol) of pyridine and 20 of water was added dropwise. The mixture is stirred at ao-30 for 1 h and concentrated under reduced pressure. The residue is extracted with 1001 chloroform. Extract twice), 50 MP of water, dried with anhydrous calcium chloride and concentrated under reduced pressure. By recrystallization of the solid residue from ethanol, 0.47 g (30% yield) of 2,3-dicycall-5-n-1-lolino-b-Sbensilthio pyrazine with m.p. 153-155 ,. Calculated,%: C 62.11; H 4; 39 | N 22.64. “BUtfN S Naydeyo,%: C 62.44; H 4.80; N 22.50. According to the procedure of Example 27, compounds 221-225 were synthesized as shown in Table. Example 28. Preparation of 2,3-dicyano-5,6-bis (methylthio / pyrazine, 1.89 g (0.01 mol; 2,3-dicyahio-5,6-dichloropyrazine) dissolved in 30 ml of acetone. The resulting solution is cooled before stirring and 7 g of a 20% aqueous solution of methyl mercaptan sodium salt is added dropwise to it under stirring for 10 minutes. The mixture is transmuted for 1 h. After the reaction is complete, the reaction mixture is concentrated under reduced pressure. The mixtures are washed with 50 ml of water, dried and recrystallized from ethanol to give 1.64 g (74% yield) of 2,3-dicyano-5, b-bis (m ethylthio pyrazine with a melting range of 139-142. Calculated: C 43.23; H 2.72; N 25.20. SvHbM45 1 Found,%: 43.40; And 2.70; N 25, 03. According to the procedure of Example 28, semi-pure compounds 226-234, presented in the following procedure: 1. 2,3-Dicyanopyrazine derivatives of general formula I have the ability to inhibit seed germination, loosening and / or contribute to inhaling their stems and leaves and thus, they exhibit herbicidal action as an active ingredient of pre-emergent herbicides and / or after emergence herbicides when working the soil flooded with water, when treating the leaves in the stage growth of weeds, when dry cultivation of the soil, etc. In particular, these compounds have herbicidal activity in flooded low-lying fields or rice crops containing excess water, and can be advantageously used as an active ingredient in herbicides applied to rice crops. Compounds of formula 1; selective herbicidal activity and can effectively control harmful weeds, in essence, do not have a damaging effect on beneficial agricultural or horticultural crops such as rice, barley, wheat, and OBOtw. For example, when treating flooded soil with PSD on rice, the compounds of formula 1 can selectively destroy Echlnochrt. Ipa oryzicola. Is a typical sorn for the Gramlneous family without significant damage to rice, which also belongs to the Gramineous family. Compounds of formula i exhibit a herbicidal effect against paddy weeds sleduyugtsim sowing ComposItae (vtdens trlpartlta, etc.) j ScrophularIaceae (Oopatrlum Janceum, Vandellla angustlfolta, Oe) c jnostema violaceum Llndernlca procumbens, eta).; Lythraceae (Ammannla multlflora, Rotala l, ndlc &, Lythrum anceps, et8. Elattnaceae (Elatlne triandra, etc.fl ,: Ca1 1 1 tr Ichaceae (CallltrHha ver na, et p.); Onagraceae (Ludwigia prostrata, ethere, aetra, et chin ver, et s.); Onagraceae (Ludwigia prostrata et chin ver, et s.) Polygonum Hydropiper, etc), Ponteder1aceae (Monochoria vaglnalis, etc.) Erlocaulaceae (Eriocaulon Sleboldtianura, Eriocaulon Miquellanum, etc.) ;. Lemnaceae (SpJirodela poyrhlza, Lemna pauc1 costate, Lemna trlsulca, etc.), Cyperaceae (Suregiz difformis, Eleocharls acicuiarls , Flmbrlstylia mtliaceae, Cyperussbrotlnus, Eclrpus} uncoldes, etc.) {Gramlneae (Echlnochloa oryzlcola Hymenachuc -Indlca, etc.) j Hydrocharttaceae (BIyxa ceratosperma, ottelia aHsmolses, you will also find the same items in which you will be looking for, and you will be looking for, and you will be looking for, and you will be looking for, what you and your company will have for you, but you will need to find it. agittar pygmaea, Sagittar a aglnashi, etc.)., MarsMeaceae (Marsllea quadrifolla, etc.); Zygnemataceae (Spirogyra arela, et p.) iet with, and weedless soil weeds, such as Composltae (Ertger on annus, ErIgeron phI 1ade1phicus, Qallnsoga clIlata, Erigeron canadensls, Taraxacum offlclnale, etc.), Rublaceae (Gallam Aparlne, etc.) Serophu1 ariaceae (Veronica dtdyma, etc,) / Solanaceae (Solanum nigrum etc.) / Solanaceae (Solanum nigrum etc.) Convolva1aceae (Calystegia hederacea, etc.), Euphorblaceae (Euphorbia suplna, etc.); Oxalldaceae (Oxalls cornlculate, Oxatis Martiana, etc.); Cructferae (Capsella bursa-pasto rls, Raphanus raphanIstrum, Brassic n i gra, etc.); Caryfiphy) 1aceae (Stellarla Alsln Cerastium hoiosteoIdes, Stellarla Media, etc.), Ama ran thaceae (Amaranthus vir I d I. Amaranthas llvldus, etc.) perslaria, Rumex japonlcus, etc.)} Cyperace, ae (Cyperus cotundus, Cyperus Znia, etc,), Gramlneae (Alopecurus aegualls, DIgltaria adscendens, Poa annua, Eleuslne Indica, Echlnochloa crusgallI, etc.). The following examples show the herbicidal activity of the compounds of formula 1 on plants. Example 1. Treatment of flooded soil. Filled polyethylene pots (1/5; 000, ap) soil for rice crops (seeds suglinistoyu and sealed Echlnochloa oryzicola, broadleaf weeds Monochoria vaglnalls, Rotata tndica, Lendernia procumbens and Sclrpus junco ides a depth of 2 cm and transplanted seedling two Eleocharlaaclcularis. At the same time, sprouts of rice are transplanted in a 2–3 leaf stage with groups of two sprouts to a depth of 2 cm and poured up to 1 cm above 3 cm above the soil surface. Weigh a wettable powder containing one of the compounds of formula 1, dilute 10 ksh of water and droplets deposited on the surface of the water. Then the rice The plants are kept in a glass chamber and, after 3 weeks after treatment, the herbicidal effect of the active compound and its effect on rice are evaluated, the results of which are shown in Table 3. Herbicidal activity is evaluated according to the scheme shown in Table 2. Example 2 Sheet processing., Seeds of rice, wheat. Pan I cum - cru S-gaHi, Olgltaria adscendens, Amarant thus vlrldis and radishes are sown in unglazed pots filled with j moss soil and covered with a B.1 cm thick soil layer. When the plants are raised and reach Stages of 3-4 leaves, sprayed diluted wettable powder, which contains one of the compounds of the formula i, at a dose of 100 l / 1p ar. On the 15th. The day after treatment, the degree of damage to each plant is evaluated (the results were evaluated in the same manner as in Example 1), the results of which are given in Table. 4. Example 3. Tillage in elevated conditions. The soil from the hill is placed in plastic pots, sown wheat, rice, radishes, corn and soybeans and covered with soil containing seeds: -O fg 1 tar 1а adscendes, EchlnochJ oa crus-gain and Amarant vlrldesTOJOn1799760818

2 cm thick. Immediately after this, the next 3 weeks are sprayed. in a glass chamber ,,

wetted powder containing co-results are given in table. 5 (gerination of formula 1 at a dose of 200 l /. The atsidin activity is evaluated as

/ 10 ar. The plants are then examined as in Example 1).

Table,

Continued table. one

Continued table. one

Continued table. one

Continued table. one

Continued table. one

Continued table. one

Continued table. one

Continued table. one

Continued table. 3

37

38

997608 Continuation. 3

LTD

2000

one

1000

500

2000

2 1000 500 2000

13 1000 500 250 2000

14 1000 500 250 2000

15 1000 500 250 2000

16 17 2000 1000 2000

18 19 20 1000 2000 1000 2000 1000 500 250

2

55

1 O 5 5 5 4

Oh oh

one

five

ABOUT

4.5

about

ABOUT

four

4.5

five

5 5 5 5 5 5 5

four

five

four

4.5

3

four

4.5

five

2

five

ABOUT

3

ABOUT

ABOUT

4.5

4.5

5 5 3 5 5 5

four

five

four

five

3

five

4.5

Q 2 1

2

2

five

five.

five

4 5 5 5

four

, 2 1 3 2 2 1 О О

four

four

2

3

four

- 5 5 5 5 5 5

3

g

3

five

four

 5 5 4

four

3

2.5

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued tabl, 3

Prolonging table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Continued table. 3

Table

Continued table. four

1.0

about

1.0

about

1.0

about

0.5

about

0.25

about

1.0

about

0.5

about

1.0

o1, 0

about

1.0

about

1.0

about

1.0

about

1.0

about

1.0

about

Continued table. four

0.5

4 5 5 4 4 5 3 4 3 3 3 3 3 1 4

four

ABOUT

3.5

five

five

four

five

four

four

five

five

3

five

2

five

2

3

one

four

five

five

four

ABOUT

five

0.5

five

2

2T a b l and c-a

Continued table. five

one or two substituents from the number of halogen, nitro, methyl, methoxy, carboxyalkoxy-alkoxycarboxy, alkoxy or apcanoyloxy, in which alkyl with 1-3 carbon atoms, methylamiocarbonyloxy, H-methylureido group or. a forchch / ly group, where R and P are hydrogen, unsubstituted alkyl with 1-6 carbon atoms or substituted by one or two substituents from the number of halogen, cyano, hydroxy or alnoxy group, where alkyl with 1-3 carbon atoms, carboxyl, ethoxycarbonyl, alkanoyl with 1 to 3 carbon atoms, diethy amino, phenyl or tolyl / alpyl, cyclohexyl, unsubstituted phenyl or substituted by one or two substituents from the number of halo, trifluoromethyl,

alkyl with 1-3 carbon atoms or alkoxy with 1-3 carbon atoms, or

4 together with the common nitrogen atom form a 3-7-membered nitrogen-containing cycle or morpholine.

01.20.78.

A - all meanings;

B is an unsubstituted hydroxy group with 1 to 3 carbon atoms or substituted by carboxyl, or ethoxycarbonyl, an unsubstituted phenylthio group or substituted by halide or methyl, a benzyl thio group, a halobenzylthio group. I Sources of information taken into account in the examination

1. Heterocyclic compounds. Ed. R. Elderfield. T. b, M., Foreign literature, 1960, p. 330.

Claims (5)

Claim The method of obtaining derivatives 2 3-dicyanopyrazine of the general formula where A is hydrogen, methoxy, alkyl with 1-6 carbon atoms, benzyl, unsubstituted phenyl or substituted with methyl, one or two halogens, nitro, trifluoromethyl, cyano, one or. two alkoxyls with 1-2 carbon atoms, an unsubstituted phenoxy group or substituted by a methoxy group or one or two halogen atoms / alkthio group with 1- 4 carbon atoms; ' unsubstituted phenylthio group or substituted by a halogen, or β-50-zylthio group) B is an unsubstituted alkthio group with 1-3 carbon atoms or substituted by a carboxyl or ethoxycarbonyl) propynyloxy, allyloxy, where A has an unsubstituted phenoxy group or substituted 55 χ - halogen, one or two substituents from the number of halogen, nitro group, methyl, methoxy group, carboxyalkoxy, alkoxycarboxyalkoxy · ?, apkanyloxy group in which alkyl with 1-3 carbon atoms, methylaminocarbonyloxy, methoxycarbonylamino or N-methylureido groups; unsubstituted fendlthio group or substituted by halogen, or methylbenzylthio group. Continuation of the table 5 'halobenzylthio group or a group of the formula. NR ^ R ^, where R <and R ₂ - hydrogen, unsubstituted alkyl with 1-6 carbon atoms, or substituted by one or two substituents from among the halogen, cyano, hydroxy or alkoxy group, where alkyl with 1-3 carbon atoms; carboxyl, ethoxycarbonyl, alkanoyl with 1-3 carbon atoms, diethylamino, phenyl or tolyl, 'allyl, cyclohexyl, unsubstituted phenyl or substituted with one or two substituents from the number of halogen, trifluoromethyl, alkyl with 1-3 carbon atoms, * or alkoxyl with 1 -3 carbon atoms; or and together with a common nitrogen atom form a 3-7-membered nitrogen-containing cycle or morpholine, characterized in that, 2, 3-dicyano-5-halo-pyraein of the general formula ΙΓ indicated values, and is subjected to interaction with the compound of the general ^ formula U HB, where B has the indicated meanings. Priorities of recognition:. 12.22.77 · A - all values; A - all meanings; B - propynyloxy -, * allyloxy, unsubstituted phenoxy group or substituted by one or two substituents from the number of halogen, nitro group, methyl, methoxy group, carboxyalkoxy alkoxycarboxy, alkoxy or alkanoyloxy group, in which alkyl with 1-3 carbon atoms, methylaminocarbon , N-methylureido group or. a group of the formula NR ^ R ^, where R ^ and R ^. - hydrogen, unsubstituted alkyl with 1-6 carbon atoms or substituted with one or two substituents from the group Galoid, cyano, hydroxy or alkoxy group, where alkyl with 1-3 carbon atoms, carboxyl, ethoxycarbonyl, alkanoyl from 1-3 carbon atoms, diethyl. amino, phenyl or tolyl / allyl, cyclo-15 hexyl, unsubstituted phenyl or substituted with one or two substituents from the number of halogen, trifluoromethyl, alkyl with 1-3 carbon atoms or alkoxide with 1-3 carbon atoms, or together with a common atom nitrogen form a 3-7-membered nitrogen-containing cycle or morpholine. 01/20/78. A - all meanings; B - unsubstituted alkylthio group with 1-3 carbon atoms or substituted by carboxyl or ethoxycarbonyl, unsubstituted phenylthio group or mixed with halogen or methyl, * benzyl (thio group, halobenzylthio group. <Sources of information taken into account in the examination 1. Heterocyclic compounds. Ed. R. Elderfield. T. 6, M., Foreign literature, 1960, p. 330.