Pyrazines

Synthetic Route of 22047-25-2, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 22047-25-2 as follows.

Weigh 1.982 g (about 0.01 mol) of bis (2-pyridine) ketone, dissolve it in 20 ml of absolute ethanol, put the solution into the flask, stir on a thermostatic heating magnetic stirrer, and weigh 1.221 g (about 0.01 mol) ) 2-Acetylpyrazine was added to the solution, and the reaction was carried out at 50 C under constant temperature and reflux for 3 hours. The solution changed from colorless and transparent to orange-yellow. After the reaction was completed, the solution was filtered, and the filtrate was left to stand to evaporate naturally. Two materials were obtained, one was orange-red rod-like crystals, and the other was massive yellow crystals. The massive yellow crystals were the target product, and the yield was about 86%.

According to the analysis of related databases, 22047-25-2, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Qilu University of Technology; Tan Xuejie; Liu Shuai; Xing Dianxiang; (8 pag.)CN110606843; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 22047-25-2, name is Acetylpyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 22047-25-2, Quality Control of Acetylpyrazine

General procedure: To a stirred solution of aldehyde (10mmol) (4-(dimethylamino)benzaldehyde, 4-(1-piperidinyl)benzaldehyde, 4-(4-morpholinyl)benzaldehyde or 4-(diphenylamino)benz-aldehyde) in EtOH (75mL), ketone (20mmol) (2-acetylpyridine, 2-acetylthiazole or 2-acetylpyrazine) was added. Then KOH (1.54g, 27.5mmol) and NH3 (aq) (35mL) were added to the reaction mixture. The solution was stirred at room temperature for 24h. The solid was collected by filtration and washed with H2O. Recrystallization from ethanol (1, 4, 7, 10) or toluene (2, 3, 5, 6, 8, 9, 11, 12) afforded a crystalline solid.

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Acetylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Palion-Gazda, Joanna; Machura, Barbara; Klemens, Tomasz; Szlapa-Kula, Agata; Krompiec, Stanis?aw; Siwy, Mariola; Janeczek, Henryk; Schab-Balcerzak, Ewa; Grzelak, Justyna; Ma?kowski, Sebastian; Dyes and Pigments; vol. 166; (2019); p. 283 – 300;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., Safety of 5-Methylpyrazine-2-carboxylic acid

100.0 g (0.724 mol) of 5-methylpyrazine-2-carboxylic acid was weighed, added to 200.0 ml of purified water, and 11.5 g (0.035 mol) of sodium tungstate was added. The temperature was raised to 45.0 C, the pH was adjusted to 9.0 with sodium hydroxide, 123.0 g (1.086 mol) of 30% H 2 O 2 was added, and the reaction was stirred for 12 h. Adjust the pH to 2.0 with concentrated hydrochloric acid, then stir to the full solution, cool to 5.0 C, and stir for 3 h. After suction filtration, 105.5 g of acipimox was obtained, the yield was 94.5%, the purity was 99.94%, and the peroxide impurity was 0.006%.

The synthetic route of 5521-55-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Lunan Pharmaceutical Group Co., Ltd.; Ti Wenli; Chu Yanjun; (7 pag.)CN109438369; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4744-50-7, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 4744-50-7 name is 2,3-Pyrazinecarboxylic anhydride, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

Step 1. In a (200 mL) round bottom flask, add 2,3-pyrazine dicarboxylic anhydride (1.5 g, 0.01 mol). Under protection, add 100 ml of chloroform, heat to 80 C, stir to dissolve; then add 0.2 g of N, N-diisopropylethylamine (DIPEA) and 0.15 g of 4-dimethylaminopyridine (DMAP), and 10 mL of chloroform dissolved in aza-15-crown ether was added dropwise. 5 (2.19 g, 0,01 mol), about 20 minutes. After the dropwise addition, the reaction was held for 8 hours. After the reaction was completed, the solvent was distilled off under reduced pressure. Agent, add 0.1mol / L sulfuric acid to adjust the pH to 5; add petroleum ether to extract three times. Get “competitive” fluoride ion fluorescent probes Precursor compound 3; Yield: 78%. FIG. 7 shows a synthesis route of a precursor fluoride ion fluorescent probe precursor compound in this example.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2,3-Pyrazinecarboxylic anhydride, and friends who are interested can also refer to it.

Reference:
Patent; Xihua University; Wang Huizhen; Yong Xi; Ye Maoping; Zhou Min; Li Xin; Du Bomeng; Li Tingting; (18 pag.)CN110590761; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 59489-71-3, name is 2-Amino-5-bromopyrazine, This compound has unique chemical properties. The synthetic route is as follows., Formula: C4H4BrN3

Triisopropyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenoxy)silane (1.1 g, 2.9 mmol), 5-bromopyrazin-2-amine (507 mg, 2.9 mmol), dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (64 mg, 0.087 mmol), 1M sodium carbonate (8.7 mL, 8.7 mmol), and dioxane (10 mL) were heated in a Biotage Emrys Optimizer microwave reactor at 120 C for 10 min. The reaction was extracted with water and ethyl acetate. The organic layer was dried over magnesium sulfate, filtered and concentrated. The resulting residue was purified using silica gel chromatography (0-100% ethyl acetate in hexanes) to give a tan solid (0.8 g, 80% yield).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 59489-71-3.

Reference:
Article; Mortensen, Deborah S.; Perrin-Ninkovic, Sophie M.; Harris, Roy; Lee, Branden G.S.; Shevlin, Graziella; Hickman, Matt; Khambatta, Gody; Bisonette, Rene R.; Fultz, Kimberly E.; Sankar, Sabita; Bioorganic and Medicinal Chemistry Letters; vol. 21; 22; (2011); p. 6793 – 6799;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 875781-43-4, The chemical industry reduces the impact on the environment during synthesis 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, I believe this compound will play a more active role in future production and life.

In the reactor by adding 5-bromo-1H-pyrrolo [2,3-b] pyrazine (59.4 mg, 0 . 3mmol), step 5 the material 3-ethynyl-4-methyl-N-(4 – ((3-methyl -3,8-diazabicyclo [3.2.1] octane-8-yl) methyl) – 3 – (trifluoromethyl)-phenyl) benzamide (112 mg, 0 . 3mmol), bistriphenyl phosphorus palladium chloride (22 mg, 0 . 03mmol), three ring hexyl phosphine (16 mg, 0 . 06mmol), cuprous iodide (6 mg, 0 . 03mmol), cesium carbonate (99 mg, 0 . 3mmol), 6 drop N, N-diisopropyl ethylamine, for 80 C reaction under 12h. After the reaction, by adding ethyl acetate and ammonia-water extraction, and with a saturated NaCl solution, anhydrous Na 2 SO 4 drying, filtering, turns on lathe does, column chromatography purification to obtain a target compound.

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; NANJING SHENGHE PHARMACEUTICAL CO., LTD.; WANG, YONG; ZHAO, LIWEN; LIU, YANG; ZHANG, JINGZHONG; WANG, DEZHONG; GAO, YIPING; CHEN, HONGYAN; ZHANG, CANG; ZHANG, DI; (68 pag.)TWI523856; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 3149-28-8,Some common heterocyclic compound, 3149-28-8, name is 2-Methoxypyrazine, molecular formula is C5H6N2O, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

Representative procedure for the preparation of 1-phenoxycarbonyl-2-phenyl-3-methoxy-1,2-dihydropyrazine (3a). To a stirred solution of 2-methoxypyrazine (0.200 g, 1.816 mmol) inanhydrous THF (5 mL) was added phenylchloroformate (0.28 mL, 2.225 mmol) at 0 C andstirring was continued under nitrogen atmosphere until salt formation was completed (15 min, asdetermined by TLC on neutral alumina, EtOAc/hexanes 1:19). The reaction mixture was cooledto -41 C, a 1 M solution of phenylmagnesium bromide in THF (2.4 mL, 2.4 mmol) was addedand the mixture stirred until reaction completion (40 min, as determined by TLC on neutral SiO2,EtOAc/hexanes 1:9), and then quenched with 2 mL of aqueous 20% NH4OH/NH4Cl 1:1 (w/w).The mixture was extracted with dichloromethane (2 × 15 mL), dried over Na2SO4, andconcentrated in vacuo. Purification of the crude mixture by flash silica gel columnchromatography (0-15% EtOAc/hexanes) afforded 3a (0.488 g, 87%) as a white solid (3:2mixture of rotamers): mp: 81-82 C; 1H NMR (CDCl3, 500 MHz) delta 7.49-7.27 (m, 7H), 7.20 (t, J= 7.5 Hz, 1H), 7.12 (d, J = 8.0 Hz, 1H), 6.99 (d, J = 7.5 Hz, 1H), 6.67 and 6.63 (2d due torotamers, J = 5.5 Hz, 1H), 6.16 and 6.14 (2d due to rotamers, J = 5.0 Hz, 1H), 5.89 and 5.87 (2sdue to rotamers, 1H), 3.84 and 3.83 (2s due to rotamers, 3H); 13C NMR (CDCl3, 125 MHz) delta160.2, 160.0, 151.6, 151.5, 150.7, 150.4, 136.8, 135.9, 129.3, 128.8, 128.7, 128.6, 127.2, 126.6,125.9, 125.8, 121.3, 118.2, 118.1, 112.5, 111.8, 56.0, 54.6, 54.0, 53.9; HRMS (ESI) m/z calcdfor C18H17N2O3 [M + H]+ 309.12337, found 309.123554

The synthetic route of 3149-28-8 has been constantly updated, and we look forward to future research findings.

Reference:
Article; St Hilaire, Valentine R.; Hopkins, William E.; Miller, Yenteeo S.; Dandepally, Srinivasa R.; Williams, Alfred L.; Beilstein Journal of Organic Chemistry; vol. 15; (2019); p. 72 – 78;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 399-66-6,Some common heterocyclic compound, 399-66-6, name is [1,2,4]Triazolo[1,5-a]pyrazine, molecular formula is C5H4N4, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

Platinum(IV) oxide (2.75 g, 12.1 mmol) was added, under nitrogen, to a suspension of calcium oxide (9.30 g, 166 mmol) and [1,2,4]triazolo[1,5-a]pyrazine (18.10 g, 151 mmol) in 2-methoxyethanol (150 ml). The reaction mixture was stirred for 21.5 h under a hydrogen atmosphere, filtered over Celite, and washed with dichloromethane/ethanol (9:1). The filtrate was concentrated, coevaporated with toluene and diisopropyl ether, and then dissolved in ethyl acetate, filtered over Celite, washed with ethyl acetate and concentrated again. The residue was dissolved in hot diisopropyl ether, filtered, washed with diisopropyl ether, and concentrated for 7 h in vacuo. Yield: 17.12 g (92%)

The synthetic route of 399-66-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Gruenenthal GmbH; US2008/153843; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Recommanded Product: 5521-55-1

(1) 175 g of 5-methyl-2-pyrazinecarboxylic acid was suspended in 1 L of dioxane, then 1 L of t-butanol, 175 mL of triethylamine, and 287 mL of diphenyl azidophosphate were sequentially added to the suspension, and the reaction solution was heated to 100C. The obtained reaction solution was stirred at the same temperature for 3 hours and then cooled to room temperature, and the solvent was distilled off under reduced pressure. The residue was poured onto a saturated aqueous solution of sodium hydrogen carbonate, and the aqueous phase was extracted with ethyl acetate. The obtained extraction liquid was washed with a saturated aqueous solution of ammonium chloride and dried, and then the solvent was distilled off under reduced pressure. The obtained crude product was crystallized from acetonitrile, to obtain 158 g of the following Compound [1-1]. [Show Image] The spectral data of the compound represented by the above Formula [1-1] is presented below. 1H-NMR (CDCl3) delta: 9.15 (1H, s), 8.70 (1H, s), 7.41 (1H, brs), 2.51 (3H, s), 1.55 (9H, s). mass: 210 (M+1)+.

The synthetic route of 5-Methylpyrazine-2-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BANYU PHARMACEUTICAL CO., LTD.; EP1754706; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 54013-07-9, Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 54013-07-9, name is 5-Methoxypyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows.

General procedure: To a flame-dried flask was added 8 (0.046g, 0.142mmol), xantphos (0.016g, 0.028mmol), potassium carbonate (0.392g, 2.83mmol), palladium(II) acetate (0.003g, 0.014mmol), and the respective amine (0.170mmol). The flask was purged with nitrogen three times and then anhydrous dioxane (1.5mL) was added under nitrogen. The reaction was refluxed at 105C for 12h while under nitrogen, maintaining a positive pressure. The mixture was concentrated under reduced pressure, separated by silica column chromatography (dichloromethane/isopropanol), and purified by reverse phase chromatography (water/acetonitrile).

The chemical industry reduces the impact on the environment during synthesis 5-Methoxypyrazin-2-amine. I believe this compound will play a more active role in future production and life.

Reference:
Article; Woodring, Jennifer L.; Bachovchin, Kelly A.; Brady, Kimberly G.; Gallerstein, Mitchell F.; Erath, Jessey; Tanghe, Scott; Leed, Susan E.; Rodriguez, Ana; Mensa-Wilmot, Kojo; Sciotti, Richard J.; Pollastri, Michael P.; European Journal of Medicinal Chemistry; vol. 141; (2017); p. 446 – 459;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem