Pyrazines

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 4744-50-7 as follows. SDS of cas: 4744-50-7

EXAMPLE 1; Preparation of 3-(5-chloropyrid -2-yl) carbamoyl-pyrazine 2 carboxylic acid; In a clean, dry 500 ml R. B. flask charged acetic anhydride (162 gms) and pyrazine- 2,3, dicarboxylic acid (50 gms). The reaction mass was heated to 100-120 C. up to completion of reaction. After completion of reaction, the excess acetic anhydride was distilled under vacuum. Charged methylene dichloride (350 ml) to the above reaction mass followed by 2-amino-5- chloropyridine (40 gms) in a lot wise manner at room temperature in 30 min. The reaction mass was stirred at room temperature for 2 hrs; cooled the reaction mixture to 5-10 C. for 1 hr. The reaction mixture was filtered and washed with chilled methylene dichloride to obtain 3-(5-chloropyrid -2-yl) carbamoyl-pyrazine-2-carboxylic acid.Yield=82 gms.; EXAMPLE 2; Preparation of 6-(5-chloropyrid-2-yl) 5,7-dioxo-5,6-dihydropyrrolo [3,4-b]-pyrazine; In a clean 500 ml R. B.flask charged pyrazine-2,3-dicaroxylic acid (50 gms) and acetic anhydride (162 gms). The reaction mass was heated to 110-120 C. till the completion of reaction to get pyrazine-2,3-dicarboxylic acid anhydride. After completion of the reaction, excess acetic anhydride distilled out under vacuum and furthermore charged methylene dichloride (315 ml) and 2-amino-5-chloropyridine (40 gms) in a lot wise manner at room temperature in 30 min. Further, reaction mixture was stirred for 2 hours at room temperature. The reaction mass was cooled to 5 to 10 C. for one hour, filtered the product and washed with chilled methylene dichloride. The solid was charged with methylene dichloride (235 ml), triethylamine (40.9 ml) at temp. 0-5 C. followed by ethyl chloroformate (28.1 ml). The reaction mass was stirred at 0-5 C. for 1 hr, added water (200 ml) to the reaction mixture and stirred the mass at room temperature for 1 hr to obtain the solids. The title compound thus separated was isolated by filtration.Yield=65 gms.The HPLC purity of this above product was above 99%.

According to the analysis of related databases, 4744-50-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Sawant, Shrikant Dattatraya; Naik, Anil Mahadev; Kavishwar, Girish Arvind; Kavishwar, Smita Girish; US2008/146800; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 274-79-3, A common heterocyclic compound, 274-79-3, name is Imidazo[1,2-a]pyrazine, molecular formula is C6H5N3, 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.

Stage 2. The imidazo [1 , 2-a] pyrazine (7.2 g, 60.44 mmole) was dissolved in 2-methoxyethanol (100 ml) and Pttheta2 (1.2 g, 5.13 mmole) was added. The reaction mixture was stirred overnight at RT in an autoclave under a hydrogen atmosphere (4 bar). The autoclave was then flushed with nitrogen, the reaction mixture was filtered through filter earth, concentrated, and the solvent residues were then extracted with toluene. Purification was carried out by column chromatography on silica gel (DCM / 7 N NH3 in methanol, 95:5)

The synthetic route of 274-79-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GRUeNENTHAL GMBH; WO2009/90055; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 38557-72-1, The chemical industry reduces the impact on the environment during synthesis 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, I believe this compound will play a more active role in future production and life.

A solution of intermediate 72 (0.24 M in THF, 43 mL, 10.32 mmol) was added to a flask containing 4-bromo-2,6-dimethylpyridine (CAS: 5093-70-9, 1.75 g, 9.38 mmol) and bis(triphenylphosphine)palladium(II) dichloride (0.395 g, 0.56 mmol) under N2. Then N,N,N?,N?-tctramcthylcthylcncdiaminc (1.538 mL, 10.32 mmol) was added and the mixture was stirred at 60 C for 18 h. The mixture was quenched with the addition of a 1/1 solution of sat NH4Cl/32% aq NTb and then it was extracted with EtOAc. The organic layer was separated, dried (Na2S04), filtered and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (Si02, EtOAc in heptane 0/100 to 80/20). The desired fractions were collected and the solvents evaporated in vacuo to yield intermediate 48 (2.59 g, 955) as a yellow oil.; Intermediate 53 was prepared following an analogous procedure to the one described for the synthesis of intermediate 48 using intermediate 73 and 2-chloro-3,5- dimethylpyrazine (CAS: 38557-72-1) as starting materials.

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-Chloro-3,5-dimethylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; JANSSEN PHARMACEUTICA NV; BARTOLOME-NEBREDA, Jose Manuel; TRABANCO-SUAREZ, Andres, Avelino; MARTINEZ-VITURRO, Carlos Manuel; DELGADO-JIMENEZ, Francisca; CONDE-CEIDE, Susana; VEGA RAMIRO, Juan, Antonio; (178 pag.)WO2019/243527; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 274-79-3, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 274-79-3, name is Imidazo[1,2-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

lmidazo[1 ,2-a]pyrazine (1.191 g, 10 mmol, Intermediate 1 ) and sodium acetate (0.984 g, 12.00 mmol) were suspended in methanol (10 ml) saturated with potassium bromide (excess) and cooled to -10 0C. Bromine (0.515 ml_, 10.00 mmol) was added dropwise and the mixture stirred at -10 0C for 10 min. The solution was quenched by the addition of 1 N sodium sulfite solution (10 ml) and concentrated in vacuo. The residue was partitioned between ethyl acetate (100 ml) and 50% saturated sodium bicarbonate solution (100 ml). The aqueous phase was extracted with ethyl acetate (2 x 100 ml), combined, washed with brine (50 ml), dried over anhydrous sodium sulfate and concentrated to give crude 3-bromoimidazo[1 ,2-a]pyrazine (1.66 g, 8.38 mmol, 84 % yield) that was used in subsequent steps without further purification 3- bromoimidazo[1 ,2-a]pyrazine (1.66 g, 8.38 mmol, 84 % yield). LC/MS [M+H]+ = 198, 200, retention time = 0.53 minutes (2 minute method). 1H NMR (CDCI3, 400 MHz) d 9.09 (s, 1 H), 8.08 (s 1 H), 7.94 (s, 1 H), 7.81 (s, 1 H).

The synthetic route of Imidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GLAXO GROUP LIMITED; DEAN, David Kenneth; MUNOZ-MURIEDAS, Jorge; SIME, Mairi; STEADMAN, Jon Graham Anthony; THEWLIS, Rachel Elizabeth Anne; TRANI, Giancarlo; WALL, Ian David; WALTER, Daryl Simon; WO2010/125101; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 136927-64-5,Some common heterocyclic compound, 136927-64-5, name is 1-Chloropyrrolo[1,2-a]pyrazine, molecular formula is C7H5ClN2, 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.

To a mixture of a (248 mg, 1.0 mmol) and b (152 mg, 1.0 mmol) was added 2.0 mL of Hunig?s base (9.5 mmol).The resulting mixture was stirred at 130 C. for 3 h. After the mixture was cooled down to room temperature, 100 mL of isopropanol/chloroform (1:2) was added, and the mixture was then washed with saturated aqueous NaHCO3 (2×20 mL) and brine (2×50 mL). The organics were dried over MgS04 and concentrated under reduced pressure. The residue was purified via flash chromatography on silica gel (0-10% MeOH inEtOAc) to get the desired product as a brown powder (250 mg, 67%).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1-Chloropyrrolo[1,2-a]pyrazine, its application will become more common.

Reference:
Patent; ChemoCentryx, Inc.; Fan, Junfa; Krasinski, Antoni; Lange, Christopher W.; Lui, Rebecca M.; McMahon, Jeffrey P.; Powers, Jay P.; Zeng, Yibin; Zhang, Penglie; US2014/154179; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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 113305-94-5 as follows. category: Pyrazines

2-Amino-5-cyano pyrazine (0.25 g, 2.08 mmol) was dissolved in a mixture of 3:1 THF and DCM (40 mL) and pyridine (0.49 g, 6.2 mmol) was added. The mixture was stirred for 15 minutes then phenylchloroformate (0.97 g, 6.2 mmol) was added and the reaction mixture was heated at 50 C. for 2 hours. The reaction mixture was allowed to cool to room temperature then DCM (40 mL) and water (25 mL) were added. The separated organic layer was washed with water (2*25 mL), brine (25 mL), dried (Na2SO4) and the solvents removed under reduced pressure to give the title compound (0.8 g) which was used without further purification.

According to the analysis of related databases, 113305-94-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Boyle, Robert George; Boyce, Richard Justin; US2014/323484; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 313339-92-3, name is 3,5-Dichloropyrazine-2-carbonitrile, 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. Product Details of 313339-92-3

Preparation of compound 2Od: terf-butyl (3/?)-3-[(6-chloro-5-cyanopyrazin-2- yl)amino]piperidine-1-carboxylateTo a solution of 20c (0.6 g, 3.46 mmol) and te/f-butyl (3R)-3-aminopipehdine-1 – carboxylate (0.41 g, 2 mmol) in n-BuOH (20 ml_) was added DIPEA (1.2 ml_, 6.9 mmol) at room temperature. The resulting mixture was stirred at 50 0C for 5 h. The mixture was concentrated to dryness. The residue was purified by column chromatography (CH2CI2: CH3OH from 500:1 to 100:1 ) which gave the title compound 2Od as yellow solid (0.7 g, 60%). 1H NMR (400 MHz, CDCI3) delta ppm 1.37 (s, 9H), 1.56 (m, 1 H), 1.70 (m, 2H), 1.86 (s, 1 H), 3.36 (s, 3H), 3.57 (s, 1 H), 3.96 (s, 1 H), 5.78 (br, 1 H), 7.76 (s, 1 H).

The synthetic route of 3,5-Dichloropyrazine-2-carbonitrile has been constantly updated, and we look forward to future research findings.

Reference:
Patent; PFIZER INC.; NINKOVIC, Sacha; BRAGANZA, John Frederick; COLLINS, Michael Raymond; KATH, John Charles; LI, Hui; RICHTER, Daniel Tyler; WO2010/16005; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 486460-20-2, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 486460-20-2, name is 3-(Trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Using Procedure G-3 (Table 5) with compound 478 the title compound 479 (crude) was obtained (130 mg, 89%) as a brown oil. MS (m/z): 193.1 (M+H)

The synthetic route of 3-(Trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Forum Pharmaceuticals, Inc.; Rogers, Kathryn; Patzke, Holger; (315 pag.)US2017/749; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 486424-37-7, These common heterocyclic compound, 486424-37-7, name is 3-Amino-6-bromopyrazine-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.

Example 11 : 3-(lH-Benzimidazol-2-yl)-5-(3-pyridyloxy)pyrazin-2-amine (Compound 11-12)SCompound 11-12 METHOD K:Step 1: 3-Amino-iV-(2-aminophenyl)-6-bromopyrazine-2-carboxamide[00169] To a solution of 3-amino-6-bromopyrazine-2-carboxylic acid (140 g, 0.64 mol), o- phenylenediamine (70 g, 0.65 mol) and TBTU (247 g, 0.77 mol) in DMF (1.5 L) at 0 C was added drop wise DIPEA (166 g, 1.29 mol). The reaction mixture was stirred at room temperature overnight. The reaction mixture was poured into water and the resultant precipitate isolated by filtration and washed with water. The precipitate was dried at 50C to give the sub-title compound as a brown solid that wasused in the next step without further purification product (140 g, 70 % Yield). XH NMR (400 MHz, DMSO) delta 4.95 (br s, 2H), 6.59 (m, 1H), 6.79 (d, 1H), 6.95 (m, 1H), 7.30 (d, 1H), 7.70 (bs, 2H), 8.40 (s, 1H) and 9.65 (s, 1H) ppm; MS (ES+) 307.8.

Statistics shows that 3-Amino-6-bromopyrazine-2-carboxylic acid is playing an increasingly important role. we look forward to future research findings about 486424-37-7.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-Damien; DURRANT, Steven, John; KNEGTEL, Ronald, Marcellus, Alphonsus; O’DONNELL, Michael; REAPER, Philip, Michael; WO2011/143419; (2011); A1;,
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. 68774-77-6, name is 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine, A new synthetic method of this compound is introduced below., Recommanded Product: 68774-77-6

Add p-aminophenol (0.78 g, 7.2 mmol) and potassium tert-butoxide (1.46 g, 13.0 mmol) to the flask, use tetrahydrofuran as a solvent, and stir under an ice bath for 1 h under the protection of nitrogen; intermediate c (1 g, 6.5 mmol) and potassium iodide (0.12 g, 0.72 mmol) were added to the flask, tetrahydrofuran was used as a solvent, and the temperature was raised to 80 C., and the p-aminophenol after the reaction was added thereto, and reacted under the protection of nitrogen. After the reaction is completed, suction filtration is performed. The filtrate is spin-evaporated. After evaporation to dryness, a small amount of NaOH aqueous solution is added to sonicate, solids are precipitated, suction-filtered, and the filter cake is dried to obtain 0.45 g of a gray solid with a yield of 30.6%.

The synthetic route of 68774-77-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Jiangxi Science and Technology Normal University; Zhu Wufu; Zheng Pengwu; Xu Shan; Liu Xiaobo; Zhang Qian; Zhou Lingjia; Han Haoyun; Yu Li; Zhou Hualan; Qiu Yufeng; (25 pag.)CN110467616; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem