Tag: M.W=100-200

Adding a certain compound to certain chemical reactions, such as: 5780-66-5, name is Pyrazine-2-carbaldehyde, 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 5780-66-5, Recommanded Product: Pyrazine-2-carbaldehyde

EXAMPLE 28 To a suspension of 4 g of 5H,10H-imidazo-[1,2-a]indeno[1,2-e]pyrazin-4-one in 70 ml of dimethyl sulphoxide are added, with stirring and under cover of nitrogen, 3.9 g of 2-pyrazinecarboxaldehyde and, after cooling to 19¡ã C., 1.6 g of 60percent sodium hydride are added portionwise while maintaining the reaction medium at a temperature between 15¡ã and 21¡ã C. The stirring is continued for 4 hours and then 70 ml of water, 5 ml of acetic acid and 50 ml of methanol are successively added dropwise at a temperature in the region of 20¡ã C. The suspension obtained is filtered and the solid thus isolated is washed with methanol, air-dried and triturated in a mixture of 80 ml of dimethylformamide and 25 ml of methanol. After drying at 60¡ã C. under vacuum (1 mmHg; 0.13 kPa) 3.3 g of 10-(2-pyrazinylmethylene)-5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazin-4-one are obtained, in the form of a red-orange solid melting above 260¡ã C. (Analysis percent calculated C: 69.00, H: 3.54, N: 22.35, O: 5.11, percent found C: 69.6, H: 3.6, N: 22.0, O: 4.9).

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; Rhone-Poulenc Rorer S.A.; US5753657; (1998); A;,
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. 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., Product Details of 875781-43-4

To a solution of 2-bromo-5H-pyrrolo [2,3-b] pyrazine (3.1 g, 16 mmol)Of 1,4-dioxane (20 mL)Phosphorus oxychloride (2.27 mL, 24.1 mmol) was added to the solution andTriethylamine (220 [mu] L, 1.58 mmol)110 C for 6 hours,(50 mL x 3), dried over anhydrous sodium sulfate, and the mixture was concentrated and beaten (petroleum ether / ethyl acetate (v / v), and the mixture was stirred at room temperature (7 mL) ) = 2/1), filtration,Dried to give 1.3 g of a gray solid in 54% yield.

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference:
Patent; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Liu Bing; Huang Jiuzhong; Zheng Changchun; Zhang Yingjun; Ouyang Luo; Mao Hongfen; Nie Biao; Xu Juan; Chen Hongfen; (137 pag.)CN106336413; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 13535-07-4, 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. 13535-07-4 name is 2-Amino-5-ethylpyrazine, 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.

Pyridine (1.051 mL, 12.99 mmol) was added dropwise to a stirred solution of phenyl carbonochloridate (1.324 mL, 10.56 mmol) in dichloromethane (DCM) (20 ml) at room temperature and stirred for 30 minutes. Then 5-ethylpyrazin-2-amine (1 g, 8.12 mmol) dissolved in dichloromethane (DCM) (10 ml) was added dropwise at room temperature and stirred at 50 C. for 16 h. Allowed the reaction mixture to room temperature, diluted with DCM (3¡Á50 mL), washed with water (2¡Á30 mL) and brine (30 mL). Separated the organic layer and dried over sodium sulfate, filtered and concentrated. Residue was purified by column chromatography using silica gel (100-200 mesh) by 10% ethyl acetate in pet ether as eluent to get desired product as off white fluffy solid (1.6 g, 6.58 mmol, 81%), LCMS (m/z) 244.2 (M+H)+.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-5-ethylpyrazine, and friends who are interested can also refer to it.

Reference:
Patent; BLUM, Charles A.; Caldwell, Richard Dana; Casaubon, Rebecca; Disch, Jeremy S.; Fox, Ryan Michael; Koppetsch, Karsten; Miller, William Henry; NG, Pui Yee; Oalmann, Christopher; Perni, Robert B.; Szczepankiewicz, Bruce G.; White, Brian; US2015/152108; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 22047-25-2, The chemical industry reduces the impact on the environment during synthesis 22047-25-2, name is Acetylpyrazine, I believe this compound will play a more active role in future production and life.

General procedure: Previous method was applied to prepare Ligands (L1-L3). Piperidylthiosemicarbazide was dissolved in ethanol solution (10mL, 1mM), stirring, Corresponding aldehydes or ketones (One mole equivalent) and 5 drops of acetic acid glacial were added to it and refluxed for 4h. Filter paper was used for conquering precipitate. Rinsed the precipitate with ice-cold ethanol and dried it in a vacuum desiccator.

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; Qi, Jinxu; Yao, Qian; Tian, Liang; Wang, Yihong; European Journal of Medicinal Chemistry; vol. 158; (2018); p. 853 – 862;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

14508-49-7, name is 2-Chloropyrazine, 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. Recommanded Product: 14508-49-7

[0410] Step A: [0411] 1M aq. Na2CO3 (20 mL) and ethanol (10 mL) were added to a solution of 2-chloropyrazine (2.30 g, 20.06 mmol), 4-formylphenylboronic acid (3.90 g, 26.01 mmol) and [1,4-bis(diphenylphosphino)butane]palladium(II) dichloride (0.60 g, 0.99 mmol) in toluene (40 mL) and the mixture was heated to reflux for 18 h. The cooled reaction mixture was diluted with ethyl acetate, washed with sat. aq. NaHCO3 and brine, dried (MgSO4), and concentrated. Purification by chromatography (SiO2, 4:1 hexane/ethyl acetate) yielded 1.56 g (42%) of 4-pyrazinylbenzaldehyde.

The synthetic route of 14508-49-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Henninger, Todd C.; Macielag, Mark J.; Marinelli, Brett A.; Zhu, Bin; US2004/18994; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, 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. category: Pyrazines

General procedure: A mixture of 4-(2-aminoethyl)benzenesulfonamide (0.5 g,2.5 mmol), anhydrous sodium acetate (0.41 g, 5.0 mmol) and anacid anhydride (2.5 mmol) was stirred in glacial acetic acid(15 mL). The mixture was heated under reflux for 12 h and thereaction was monitored with the help of TLC. After completion ofreaction the solvent was removed under reduced pressure andthe crude solid obtained was washed with water, dried and recrystallisedfrom an appropriate solvent.

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

Reference:
Article; Abdel-Aziz, Alaa A.-M.; Angeli, Andrea; El-Azab, Adel S.; Abu El-Enin, Mohamed A.; Supuran, Claudiu T.; Bioorganic and Medicinal Chemistry; vol. 25; 5; (2017); p. 1666 – 1671;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 41110-28-5,Some common heterocyclic compound, 41110-28-5, name is 3-Methylpyrazine-2-carboxylic acid, molecular formula is C6H6N2O2, 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 1: Methyl 3-methylpyrazine-2-carboxylate In a 2-L flask, 3-methylpyrazine-2-carboxylic acid (Matrix, 19.95 g, 144 mmol) was suspended in MeOH (500 mL). The suspension was cooled in an ice-water bath, and concentrated sulfuric acid (Fluka, 27.3 mL, 506 mmol) was added over a time period of 5 min. The reaction mixture was heated to 80 C. for 5 h. The reaction mixture was concentrated under reduced pressure and the residue was taken up in DCM (750 mL). The excess acid was neutralized carefully with aqueous NaOH (5m, 200 mL). The aqueous layer was separated and extracted with DCM (250 mL). The combined organic layers were combined, dried over MgSO4 and concentrated to afford 16.15 g of the title compound (106 mmol, 73%). MS m/z=153 [M+H]+. Calculated for C7H8N2O2: 152.

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

Reference:
Patent; MINATTI, Ana Elena; LOW, Jonathan D.; ALLEN, Jennifer R.; CHEN, Jian; CHEN, Ning; CHENG, Yuan; JUDD, Ted; LIU, Qingyian; LOPEZ, Patricia; QIAN, Wenyuan; RUMFELT, Shannon; RZASA, Robert M.; TAMAYO, Nuria A.; XUE, Qiufen; YANG, Bryant; ZHONG, Wenge; US2014/249104; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 32493-79-1,Some common heterocyclic compound, 32493-79-1, name is 2,3-Dichloro-5,6-dimethylpyrazine, molecular formula is C6H6Cl2N2, 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.

Scheme 3, step 1 : A stirred solution of 2,3-dichloro-5,6-dimethylpyrazine (2.0 g, 11.298 mmol) and hydrazine (0.943 mL, 28.2 mmol, 95 mass%) in EtOH (15 mL) is heated at 100 C overnight. The reaction mixture is concentrated under reduced pressure to give the title compound (1.94 g, 84.6%). MS (m/z) 173 (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 2,3-Dichloro-5,6-dimethylpyrazine, its application will become more common.

Reference:
Patent; ELI LILLY AND COMPANY; CAMP, Nicholas Paul; HAMDOUCHI, Chafiq; LINESWALA, Jayana Pankaj; MORPHY, John Richard; SHI, Qing; (41 pag.)WO2019/156861; (2019); A1;,
Pyrazine – Wikipedia,
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.

EXAMPLE 8A 3-chloro-2-cyanopyrazine-1-oxide 2-Chloro-3-cyanopyrazine (5.00 g, 35.94 mmol) in concentrated H2SO4 (35 mL) at 0 C. was treated portionwise with K2S2O8 (11.65 g, 43.95 mmol), warmed to room temperature, stirred for 24 hours, treated with water, and extracted with chloroform. The organic extract was washed sequentially with water, saturated NaHCO3 and brine, dried (MgSO4) and concentrated to provide the title compound. MS (DCI/NH3) m/e 173 (M+NH4)+.

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; Abbott Laboratories; US6376488; (2002); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 4774-14-5, A common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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.

2,6-Dichloropyrazine (360 mg, 2.4 mmol), phenylboronic acid (295 mg, 2.4 mmol), tetrakis(triphenylphosphine)palladium(0) (290 mg, 0.25 mmol), potassium carbonate (333 mg, 2.4 mmol), ethanol (1 mL), and toluene (5 mL) were combined and the mixture degassed with nitrogen for 2 minutes before heating to 80C for one hour. The reaction was partitioned between ethyl acetate and water. The aqueous layer was washed with ethyl acetate (3x), the organics were combined, dried over magnesium sulfate, filtered, and concentrated. The crude material was purified by silica gel chromatography (0-30% ethyl acetate in hexanes) to give the title compound as a solid (108 mg, 0.56 mmol, 23% yield); MS (ESI) MS (ESI) m/z 191.2 [M+l]+.

The synthetic route of 4774-14-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SIGNAL PHARMACEUTICALS, LLC; WO2009/89042; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem