Pyrazines

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. 13484-56-5, name is 3-Chloro-6-methoxypyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. category: Pyrazines

Sodium hexamethyldisilazane (1M solution in THF; 0.76 ml) was added dropwise to amixture of 3-amino-2-chloro-5-methoxypyrazine (0.062 g), 4-chloro-7-(3-chloropropoxy)-3-cyano-6-methoxyquinoline (Bioorg. Med. Chem. Letters. 2000,10,2826; 0.096 g) and DMF(1.5 ml) that had been cooled to 0C. The mixture was stirred at 0C for 5 minutes and atambient temperature for 30 minutes. Acetic acid (0.023 ml) was added and the resultantmixture was evaporated. The residue was partitioned between methylene chloride and a10% aqueous sodium bicarbonate solution. The organic solution was dried over magnesiumsulphate and evaporated. The residue was triturated under diethyl ether and the resultant solidwas isolated. There was thus obtained the title compound as a solid (0.103 g); Mass Spectrum:M+lT434and436.

The synthetic route of 13484-56-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2004/108703; (2004); A1;,
Pyrazine – Wikipedia,
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Electric Literature of 22047-25-2, 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. 22047-25-2, name is Acetylpyrazine, This compound has unique chemical properties. The synthetic route is as follows.

General procedure: 1.34mL ethylenediamine (20mmol) was added to 60mL anhydrous ethanol solution of 5.09g (40mmol) of 2-acetylthiazole and stirred for 4h. The solution became slightly yellow and can be kept standing for about 10h. The white flocculent precipitate was obtained, which on re-crystallization from ethanol gave colorless crystals suitable for X-ray analysis. Yield 4.51g (16.2mmol, 81%);

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

Reference:
Article; Tan, Xue-Jie; Liu, Hai-Zhen; Ye, Chong-Zhao; Lou, Jian-Fang; Liu, Yun; Xing, Dian-Xiang; Li, Sen-Peng; Liu, Shu-Lian; Song, Lai-Zhou; Polyhedron; vol. 71; (2014); p. 119 – 132;,
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Related Products of 24241-18-7,Some common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, molecular formula is C4H3Br2N3, 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.

[00178] (Trimethylsilyl)acetylene (1.845 g, 2.655 mL, 18.78 mmol) was added dropwise to a solution of 3,5-dibromopyrazin-2-amine 1 (5 g, 19.77 mmol) in DMF (25 mL)Triethylamine (10.00 g, 13.77 mL, 98.85 mmol), copper(I) iodide (451.7 mg, 2.372 mmol) and Pd(PPh3)4 (1.142 g, 0.9885 mmol) were then added and the resulting solution stirred at RT for 30 minutes. The reaction mixture was diluted with EtOAc and water and the layers separated. The aqueous layer was extracted further with EtOAc and the combined organic layers washed with water, dried (MgS04) and concentrated in vacuo. The residue was purified by column chromatography eluting with 15% EtO Ac/Petroleum ether to give the product as a yellow solid (3.99g, 75% Yield). IH NMR (400.0 MHz, DMSO) d 0.30 (9H, s), 8.06 (IH, s); MS (ES+) 271.82

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Amino-3,5-dibromopyrazine, its application will become more common.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-Damien; STORCK, Pierre-Henri; STUDLEY, John; PIERARD, Francoise, Yvonne Theodora Marie; WO2013/49720; (2013); A1;,
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Pyrazine | C4H4N2 – PubChem

Electric Literature of 36070-79-8, These common heterocyclic compound, 36070-79-8, name is 6-Chloropyrazine-2-carboxamide, 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.

General procedure: 150 mg (0.952 mmol) of 5-Cl-PZA (1) or 6-Cl-PZA (2) was dissolved in ethanol together with triethylamine (1 eq., 96 mg, 0.952 mmol). Three equivalents of corresponding alkylamine were added to the reaction mixture and refluxed in ethanol generally for 6 hours. The completion of the reaction was checked by TLC chromatography (eluent: hexane/ethyl acetate, 1:2). The crude product was absorbed on silica by solvent evaporation and purified by flash chromatography (hexane/ethyl acetate gradient elution).

The synthetic route of 36070-79-8 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Servusova, Barbora; Paterova, Pavla; Mandikova, Jana; Kubicek, Vladimir; Kucera, Radim; Kunes, Jiri; Dolezal, Martin; Zitko, Jan; Bioorganic and Medicinal Chemistry Letters; vol. 24; 2; (2014); p. 450 – 453;,
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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. 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Computed Properties of C5H3ClN2O2

Intermediate 45; Ethyl 3-(5-chloropyrazin-2-yl)-3-oxopropanoate; 5-Chloropyrazine-2-carboxylic acid (Intermediate 44, 21 g, 0.132 mol) was taken in thionyl chloride (100 mL) which was heated to reflux for 2 h and excess thionyl chloride was distilled off under reduced pressure to obtain a residue, which was dissolved in dry tetrahydrofuran (100 rnL). In another round bottom flask ethyl hydrogen malonoate (15.8 g, 0.132 mol) was dissolved in tetrahydrofuran (500 rnL) which was cooled to 0 0C. To the resulting solution was added methyl magnesium bromide (88 mL, 0.265 M) and stirred the reaction mixture was stirred for 30 min before triethylamine (39.9 g, 0.396 M) was added. To this reaction mixture the above prepared acid chloride mixture was added, stirred for 2 h at room temperature and tetrahydrofuran was evaporated from the reaction mixture and the water (500 mL) was added and extracted with ethyl acetate (2 x 200 mL). The organic layers were combined and dried over anhydrous sodium sulphate, concentrated under reduced pressure to get obtain crude product which was purified by flash column chromatography (10% ethyl acetate / pet ether) to afford 16.0 g (53.16%) of ethyl 3-(5-chloropyrazin-2-yl)-3-oxopropanoate white solid. 1H NMR (400 MHz, CDClO: delta 1.26 (t, 3H), 1.28 (t, 3H), 4.18 (s, 2H), 4.20 (q, 2H), 4.30 (q, 2H), 6.28 (s, IH), 8.57 (s, IH), 8.61 (s, IH), 8.89 (s, IH), 9.04 (s, IH), 12.35 (s, IH). Mass (APCI): m/z 227 (M-H).

The synthetic route of 36070-80-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; BASARAB, Gregory, Steven; HILL, Pamela; SHERER, Brian; ZHOU, Fei; WO2010/67123; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 54013-06-8, name is Ethyl 5-aminopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Formula: C7H9N3O2

Intermediate Example lnt-5: Ethyl 2-(4-{1-[(ferf-butoxycarbonyl)amino]cyclobutyl}phenyl)-3-phenyl- imidazo[1,2-a]pyrazine-6-carboxylate To a mixture of crude fert-butyl (1-{4-[bromo(phenyl)acetyl]phenyl}cyclobutyl)- carbamate [lnt-1-A] (213 mg, 0.38 mmol, 1.0 eq), ethyl 5-aminopyrazine-2- carboxylate (CAS-Nr. 54013-06-8, 70.5 mg, 0.42 mmol, 1.1 eq.) and diisopropylethylamine (0.055 ml_, 0.42 mmol, 1.1 eq) in 2.3 ml_ butyronitrile was added pre- dried 3A mol sieves. The mixture was heated overnight at 120. The reaction mixture was partitioned between DCM/water and was filtered through a phase separator. The remaining volatile organic components were removed by the use of a rotary evaporator. In parallel we conducted the same experiment in the absence of diisopropylethylamine following the same protocol. The crude materials of both experiments were combined and purified via MPLC (Biotage Isolera, 25 g Snap- cartridge; eluent: hexane/ethyl acetate (1/1) -> ethyl acetate) to deliver 69 mg (14%, yield based on combined amount of fert-butyl (1-{4-[bromo(phenyl)acetyl]- phenyl}cyclobutyl)carbamate) of the title compound. UPLC-MS (Method 1): RT = 1.43 min; m/z = 513 (M+H) +.

The synthetic route of 54013-06-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER INTELLECTUAL PROPERTY GMBH; BAYER PHARMA AKTIENGESELLSCHAFT; BAeRFACKER, Lars; SCOTT, William; HAeGEBARTH, Andrea; INCE, Stuart; REHWINKEL, Hartmut; POLITZ, Oliver; NEUHAUS, Roland; BOeMER, Ulf; WO2013/104610; (2013); A1;,
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Pyrazine | C4H4N2 – PubChem

Application of 55557-52-3,Some common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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.

(3) 2.78 g (7.0 mmol) of 19-2 was added to a 100 mL three-necked flask.1.12 g (8.0 mmol) of 2-chloro-3-cyanopyrazine, 78.5 mg (0.35 mmol) of palladium acetate,290 mg (0.7 mmol) of X-Phos, 2.90 g of anhydrous potassium carbonate, and three times of deaeration with nitrogen.12 mL and 6 mL of deionized water were injected, nitrogen was bubbled for 30 min, and heated at 100 C for 8 h.After the TCL monitoring reaction was completed, it was cooled to room temperature, extracted with 100 mL of dichloromethane and 200 mL of deionized water.The organic phase was washed three times with deionized water (100 mL × 3) and dried over anhydrous sodium sulfate for 10 min.After filtration and concentration, the crude product was passed through a silica gel column (5×10 cm), and the pure product was separated and dried in vacuo.Product 19 (TCzPZCN) 4.01 g was obtained in a yield of 58%.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-Chloropyrazine-2-carbonitrile, its application will become more common.

Reference:
Patent; Zhejiang Hongwu Technology Co., Ltd.; Ai Qi; Liu Junyuan; Duan Ke; Zhang Qisheng; (33 pag.)CN110256409; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 28643-16-5, name is Methyl 3-amino-5-chloropyrazine-2-carboxylate, 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: 28643-16-5

a) 3-Amino-5-methoxy-pyrazine-2-carboxylic acid methyl ester At 0 C. 75 mg (1.866 mmol) 60% sodium hydride in oil was added in portions to 5 ml MeOH and the mixture was stirred at room temperature for 30 min. After re-cooling to 0 C. 350 mg (1.866 mmol) 3-amino-5-chloro-pyrazine-2-carboxylic acid methyl ester (GB 1248146) was added and the mixture was allowed to warm to room temperature and stirred over night. Saturated aqueous NH4Cl was added and the mixture was extracted with DCM and EtOAc, the combined organic layers were washed with saturated aqueous sodium chloride, dried with Na2SO4 and evaporated. The residue was purified by chromatography on silica gel (cyclohexane to EtOAc) to provide the title compound as colorless solid. HPLC: RtH10=0.61 min; ESIMS [M+H]+=184.2; 1H-NMR (360 MHz, DMSO-d6): 7.52 (s, 1H), 7.49 (br s, 2H), 3.91 (s, 3H), 3.81 (s, 3H).

The synthetic route of Methyl 3-amino-5-chloropyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Novartis AG; US8338413; (2012); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 58138-79-7, name is 2,6-Diiodopyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 2,6-Diiodopyrazine

1. 2-Iodo-6-dimethylaminopyrazine A solution of 2,6-diiodopyrazine (6 g, 18.1 mmol) in methanol (50 ml) and dimethylamine (40% aqueous solution, 200 ml) was heated at reflux for 1 h. The methanol was removed under vacuum, the aqueous saturated with potassium carbonate and extracted with dichloromethane (3*100 ml). The combined extracts were dried (Na2 SO4), evaporated and the residue purified by chromatography through silica-gel eluding with dichloromethane. The product (4 g) was obtained as a low melting solid, m.p. 46-48 C., m/e 249 (M+); delta (360 MHz, CDCl3) 3.10 (6H, s, 2*Me); 7.87 (1H, s, pyrazine-H); 8.01 (1H, s, pyrazine-H).

The synthetic route of 58138-79-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Merck Sharp & Dohme Limited; US5260293; (1993); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, 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 21279-62-9, Quality Control of 3-Chloropyrazine-2-carboxamide

Compound 9 is prepared by reaction of 4-chlorophenylbydrazine (3 mmol) with 3- chloropyrazine-2-carboxamide (ifi, 1 mmol) in 3 mL methanol and pyridine (1 inmol). The reaction is performed in a microwave reactor at the temperature 140 C, pressure 15 kPa and an output of 120 W during 30 miii. After completing the reaction, product 9 was isolated and purified by column chromatography on silica gel (mobile phase: hexane I ethyl acetate 1:1), yield 23%. Analytical data for compound 9: Brown crystalline solid; Mp. 155.3-156.2C; Elemental analysis calculated for C,1H10C1N5O (m.w. 263.68): 50.10% C, 3.82% H, 26.56% N; found 50.27% C, 3.72% H, 26.3 5% N; IR (ATR-Ge, cm?): 3453 (-NH-), 3202 (-CONH2), 1686 (-C=O), 1596, 1527, 1491, 1405 (pyr); ?H-NMR (300 MHz, CDCI3) oe 11.40 (IH, bs, NH), 8.45 (1H, bs, NH), 8.40 (111, d, J 2.3 Hz, H5), 8.05 (1H, d, J- 2.3 Hz, H6), 8.01 (1H, bs, NH), 7.75-7.67 (211, m, AA?, BB?, H2?, H6?), 7,40-7.32 (211, m, AA?, BE?, H3?, H5??); ?3C NMR (75 M}lz, DMSO) 8 168.9, 151.7, 145.8, 138.3, 132.9, 128.9, 127.7, 126.1, 121.4; Lipophilicity: calc. values log? = 0.34; experimental determined values log k = 0.5996.

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

Reference:
Patent; UNIVERZITA KARLOVA V PRAZE; DOLEZAL, Martin; ZITKO, Jan; JANDOUREK, Ondrej; SERVUSOVA-VANASKOVA, Barbora; (31 pag.)WO2016/95877; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem