Pyrazines

Electric Literature of 19745-07-4, 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. 19745-07-4, name is 2,5-Dichloropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

A mixture of 2,5-dichloropyrazine 3.0 g, sodium hydride (60percent, oil) 880 ml, and NMP 50 ml was added to 2.3 g of benzyl alcohol under ice-cooling. The reaction mixture was warmed to room temperature and stirred at room temperature for 5 hours. The resulting reaction mixture was added with water and extracted with ethyl acetate. The resulting organic layer was washed with saturated brine, dried over sodium sulfate, concentrated under reduced pressure, and the resulting residue was subjected to silica gel column chromatography to give 3. lg of an intermediate of the following formula 1 .

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, 2,5-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; SUMITOMO CHEMICAL COMPANY, LIMITED; ORIMOTO, KOHEI; NOKURA, YOSHIHIKO; NAKAJIMA, YUJI; TANABE, TAKAMASA; KIMURA, TAKAHIRO; (305 pag.)TW2017/26631; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 13924-94-2,Some common heterocyclic compound, 13924-94-2, name is Methyl 5-aminopyrazine-2-carboxylate, molecular formula is C6H7N3O2, 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.

A solution of methyl 5-aminopyrazine-2-carboxylate (2 g, 13.06 mmol, 1.00 equiv), N-bromosuccinimide (2.8 g, 15.73 mmol, 1.20 equiv) in acetonitrile (30 mL) was stirred overnight at room temperature. The reaction mixture was directly concentrated under vacuum and the residue was purified by silica gel chromatography eluting with ethyl acetate/petroleum ether (1:1) to afford 1.6 g (53%) of the title compound as a yellow solid. LC-MS (ES, m/z): 232[M+H]+.

The synthetic route of 13924-94-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Genentech, Inc.; Blaquiere, Nicole; Castanedo, Georgette; Feng, Jianwen A.; Hu, Baihua; Staben, Steven; Yuen, Po-wai; Wu, Guosheng; Lin, Xingyu; Burch, Jason; US2015/57260; (2015); 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 33332-29-5 as follows. COA of Formula: C4H4ClN3

(iii) 2-Amino-5-chloropyrazine (1.7 g) was dissolved in chloroform (190 ml) and pyridine (1.3 ml) was added under an argon atmosphere. The flask and its contents were protected from light and a solution of bromine (0.7 ml) in chloroform (85 ml) was added over a period of 1 hour. After stirring for 2 hours more bromine (0.07 ml) in chloroform (8.5 ml) was added and, after stirring for 30 minutes, pyridine (0.2 ml) was added. The reaction mixture was stirred for a further 30 minutes then washed with water (50 ml) and the organic phase was separated. The solvent was removed by evaporation and the residue was purified by chromatography through a bed of silica (90 g), eluding with hexane (200 ml) followed by dichloromethane. Dichloromethane fractions containing the product were evaporated to give 2-amino-3-bromo-5-chloropyrazine (1.68 g); 1 H NMR (d6 DMSO): 6.94 (br s, 2H), 8.09 (s, 1H); mass spectrum (+ve CI): 208 (M+H)+.

According to the analysis of related databases, 33332-29-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Zeneca Ltd.; US5668137; (1997); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 4430-75-5,Some common heterocyclic compound, 4430-75-5, name is Octahydro-2H-pyrido[1,2-a]pyrazine, molecular formula is C8H16N2, 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.

Step 12a:; A solution of acid 49 (50 mg, 0.125 mmol) in CH2C12 (2 mL) was treated with oxalyl chloride (100 muL, 1.16 mmol). After 20 min, the reaction mixture was concentrated in vacuo, diluted with CH2CI2 (1 mL) and treated with Et3N (130 muL, 1.20 mmol) followed by (+/-)-1,4-diazabicyclo[4.4.0]decane (140 mg, 1.0 mmol). After 18 h, the reaction mixture was diluted with saturated aqueous NH4CI and extracted with CH2CI2 (2x). The combined organic layers were washed with saturated aqueous NaHC03, dried over MgS04 and concentrated in vacuo. Preparative TLC (0.5:4.5:95 NH40H/MeOH/CH2CI2), afforded Example 40 (42.0 mg, 65%) as a yellow oil. Example 40: LCMS (ES): time 3.45 min, m/z 520.3 (M+H+).

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

Reference:
Patent; SCHERING CORPORATION; WO2005/97768; (2005); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 78342-42-4, name is (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, 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 78342-42-4, Recommanded Product: (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine

INTERMEDIATE 2; (3R)-3-f (l, 1-Dimethylethoxycarbonyl) aminol-4-r2-fluoro-4- (trifluoromethyl) phenyll- butanoic acid; Step A. (2R, 5S)-2, 5-Dihydro-3 6-dimethoxy-2-(2′-fluoro-4′- (trifluoromethyl) benzyl)-5-isopropylpyrazine ; To a solution of 3.32 g (18 mmol) of commercially available (2S)-2, 5- dihydro-3,6-dimethoxy-2-isopropylpyrazine in 100 mL of tetrahydrofuran at-70 °C was added 12 mL (19 mmol) of a 1.6M solution of butyllithium in hexanes. After stirring at this temperature for 20 min, 5 g (19.5 mmol) of 2-fluoro-4- trifluoromethylbenzyl bromide in 20 mL of tetrahydrofuran was added and stirring was continued for 3 h before warming the reaction to ambient temperature. The reaction was quenched with water, concentrated in vacuo, and extracted with ethyl acetate. The combined organic phase was washed with brine, dried, and concentrated in vacuo. Purification by flash chromatography (silica gel, 0-5percent ethyl acetate in hexanes) afforded 5.5 g of the title compound. 1H NMR (500 MHz, CDC13) 6 7.33- 7.25 (m, 3H), 4.35-4. 31 (m, 1H), 3.75 (s, 3H), 3.65 (s, 3H), 3.60 (t, 1H, J = 3.4 Hz), 3.33 (dd, 1H, J = 4.6, 13.5 Hz), 3.03 (dd, 1H, J = 7,13. 5 Hz), 2.25-2. 15 (m, 1H), 1.0 (d, 3H, J = 7 Hz), 0.66 (d, 3H, J = 7 Hz).

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Patent; MERCK & CO., INC.; WO2003/82817; (2003); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 55557-52-3, The chemical industry reduces the impact on the environment during synthesis 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, I believe this compound will play a more active role in future production and life.

3-Chloro-2-cyanopyrazine (2.24 g, 1.6 eq), 4-amino-2-pyrimidinecarboxylic acid(1.39g, 1eq) and potassium carbonate(4.1g, 3eq) solution in 20mL DMF, stirred and heated to 60 C, reaction for 5h,Cool to room temperature, filter, and refine the solution with (DCM / MeOH = 20:1).Obtained a yellowish solid product 1.73g(Yield: 71%).

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, 3-Chloropyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Jiangxi Runze Pharmaceutical Co., Ltd.; Liao Niansheng; Hu Xiande; Zhou Liming; Sui Guilan; (22 pag.)CN109568256; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 63286-28-2,Some common heterocyclic compound, 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, molecular formula is C4H5ClN4, 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.

Reference Example 141-2 Preparation of N’-(3-chloropyrazin-2-yl)cyclohexanecarbohydrazide To a mixture of 2-chloro-3-hydrazinylpyrazine (1.10 g), triethylamine (1.27 mL), and chloroform (38 mL) in a 200 mL eggplant flask was added cyclohexanecarbonyl chloride (1.13 mL) under ice-cooling, and the resulting mixture was stirred at room temperature for 1 hour. To the reaction mixture were added a saturated aqueous solution of sodium hydrogen carbonate (40 mL), saturated brine (40 mL), and ethyl acetate (120 mL), and the resulting mixture was stirred for a while. The resulting organic layer was separated, washed with saturated brine, dried over anhydrous sodium sulfate, and the insoluble matters were removed by filtration. The resulting filtrate was concentrated under reduced pressure to give the title compound (1.53 g) (yield 79%) as a pale yellow solid. MS(ESI) m/z: 255/257 [M+H]+

The synthetic route of 63286-28-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MITSUBISHI TANABE PHARMA CORPORATION; UBE INDUSTRIES, LTD.; NAKAJIMA, Tatsuo; HAYASHI, Norimitsu; ISHIZAWA, Kouhei; TSUZAKI, Yasunori; IWAMURA, Ryo; TSUBOIKE, Kazunari; US2019/185479; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 113305-94-5, 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. 113305-94-5, name is 5-Aminopyrazine-2-carbonitrile belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Example 298a (4-{5-[(5-Cyanopyrazin-2-yl)amino]-1-methyl-6-oxo-1,6-dihydropyridin-3-yl}-2-{4,4-dimethyl-9-oxo-1,10-diazatricyclo[6.4.0.02,6]dodeca-2(6),7-dien-10-yl}pyridin-3-yl)methyl aAcetate 298a A 50-mL round-bottomed flask equipped with a reflux condenser was charged with [4-(5-bromo-1-methyl-6-oxo-1,6-dihydropyridin-3-yl)-2-{4,4-dimethyl-9-oxo-1,10-diazatricy-clo[6.4.0.02,6]dodeca-2(6),7-dien-10-yl}pyridin-3-yl]methyl acetate 273a (269 mg, 0.50 mmol), 5-aminopyrazine-2-carbonitrile (60 mg, 0.50 mmol), XantPhos (29 mg, 0.050 mmol), Pd2(dba)3 (45 mg, 0.050 mmol), Cs2CO3 (326 mg, 1.0 mmol), and 1,4-dioxane (10 mL). The reaction mixture was heated at 100C under microwave irradiation for 1h after three times atmosphere/argon flush. The mixture was filtered off and the solid was washed with methanol (50 mL). The combined filtrate was evaporated under reduced pressure and the residue was purified with silica-gel column chromatography eluting with 50:1 dichloromethane/methanol to afford 298a (200 mg, 69%) as yellow solid. MS-ESI: [M+H]+ 579.3.

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, 5-Aminopyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; F.Hoffmann-La Roche AG; CRAWFORD, James John; ORTWINE, Daniel Fred; WEI, BinQing; YOUNG, Wendy B.; EP2773638; (2015); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 160252-31-3, 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. 160252-31-3 name is 1-(5-Chloropyrazin-2-yl)ethanone, 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: 1-(5-(4-fluoro-1H-pyrazol-1-yl)pyrazin-2-yl)ethan-1-one Sodium hydride (60 wt %, 276 mg, 6.90 mmol) was added to a mixture of 1-(5-chloropyrazin-2-yl)ethanone (800 mg, 5.11 mmol) and 4-Fluoro-1H-pyrazole (484 mg, 5.62 mmol) in N,N-dimethylformamide (6.0 mL) at ambient temperature for 10 minutes. The reaction mixture was then poured into water (70 mL) and was sonicated and stirred for 20 minutes. A dark red solid was isolated by filtration, washed with small amounts of water, and dried to 1-(5-(4-fluoro-1H-pyrazol-1-yl)pyrazin-2-yl)ethan-1-one (919 mg, 95% yield). MS: M+1=207.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 1-(5-Chloropyrazin-2-yl)ethanone, and friends who are interested can also refer to it.

Reference:
Patent; BLUEPRINT MEDICINES CORPORATION; Kim, Joseph L.; Kevin, Douglas J.; Brubaker, Jason D.; (57 pag.)US2017/267661; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

5521-58-4, name is 5-Methylpyrazin-2-amine, belongs to pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Computed Properties of C5H7N3

Palladium (II) acetate (lOmg) and 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene(40mg) were added to a mixture of S-4-chloro-6-methyl-2-{2-[3-(pyrid-2-yl)isoxazol-5- yl]pyrrolidin-l-yl}pyrimidine (272mg, 0.80mmol), 2-amino-5-methylpyrazine (85mg, 0.78mmol) and cesium carbonate in 1,4-dioxane (5ml) under nitrogen. The mixture was heated at 100C in a sealed vessel under microwave irradiation for 18 hours. The solution was allowed to cool, the insolubles were removed by filtration and the solvent was removed from the filtrate by evaporation. The residue was purified by column chromatography on silica gel eluting with EtOAc / hexane (25:75 increasing in polarity to 0:100). The purified product was triturated with ether and hexane and the solid collected by filtration to give the title compound (174mg, 53%); NMR (398K) 2.03-2.15 (2H, m), 2.15-2.20 (IH, m), 2.15 (3H, s), 2.35-2.45 (IH, m), 2.38 (3H, s), 3.70-3.75 (IH, m), 3.76-3.84 (IH, m), 5.45-5.55 (IH, m), 6.48 (IH, s), 6.65 (IH, s), 7.40-7.46 (IH, m), 7.85-7.90 (IH, m), 7.90-7.95 (IH, d), 8.10 (IH, s), 8.61-8.65 (IH, d), 9.10 (IH, s), 9.30-9.35 (IH, br s); m/z 415 [MH]+ .

The synthetic route of 5521-58-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2007/31745; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem