Category: Pyrazines

6705-33-5,Some common heterocyclic compound, 6705-33-5, name is Pyrazin-2-ylmethanol, 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.

To pyrazin-2-ylmethanol (1.23 g, 11.2 mmol) in SOCl2 (0.98 mL, 13.4 mmol) was added catalytic DMF. The mixture was stirred at 23C for 2 h. The mixture was concentrated in vacuo, and the crude product was used directly in the following step.

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

Reference:
Patent; VENENUM BIODESIGN LLC; LETOURNEAU, Jeffrey J; COLE, Andrew G; MARINELLI, Brett A; QUINTERO, Jorge G; (329 pag.)WO2017/214359; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 33332-29-5, name is 2-Amino-5-chloropyrazine, 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 33332-29-5, 33332-29-5

Step 2: Preparation of 2,5-dichloropyrazine; 5-Chloropyrazin-2-amine (5.0 g, 38.6 mmol) was dissolved in acetonitrile (77 ml) under a balloon of N2. The copper(I) chloride (5.7 g, 57.9 mmol) and copper(ET) chloride (7.8 g, 57.9 mmol) were added and the slurry cooled to -1O 0C with an ice:acetone bath. t-Butyl nitrite (9.15g, 89 mmol, 90%) was added dropwise and the solution allowed to warm to RT. The solution was stirred for 30 minutes until rapid gas evolution ceased. The mixture was heated to 65 0C for 2.5 hours. The mixture was cooled to RT and filtered through a 1.5 inch pad of celilte packed into a 465 ml frit. The pad was washed with DCM (200 ml x 4), the wash fractions containing the desired material combined, filtered, and concentrated in vacuo. The residue was purified by chromatography on silica gel with 2% etheI?pentane to yield the title 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-Amino-5-chloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK & CO., INC.; WO2008/85316; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

5900-13-0, 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. 5900-13-0, name is 5-Bromo-3-methoxypyrazin-2-amine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Synthesis of N-(5 -bromo-3 -methochiypyrazin-2- vDformamide [0207][0208]Acetic anhydride (150 ml) was added dropwise to formic acid (150 ml) under ice- cooling, followed by stirring at the same temperature for 25 minutes. A solution of 5-bromo-3- methoxypyrazin-2-ylamine (CAS No.5900-13-0, 38.7 g) in THF (200 ml) was added dropwise to the reaction mixture over 10 minutes, and then the reaction solution was stirred at room temperature for one hour. Ice water was added to the reaction solution, and the precipitated powder was collected by filtration. The resulting powder was washed with water and then air- dried overnight to obtain 41.2 g of the title compound. The property values of the compound are as follows.1 H-NMR (CDCl3 ) delta (ppm): 4.06 (s, 3H), 7.87 (s, IH), 7.87 (brd, J = 11.0 Hz, IH), 9.37 (d, J =11.0 Hz5 IH).

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

Reference:
Patent; Eisai R&;D Management CO., LTD.; HASEGAWA, Daiju; KITAZAWA, Noritaka; WO2010/98495; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below.

Step 1: Synthesis of 5-Bromo-3-trimethylsilanylethynyl-pyrazm-2-yIamine.[0282] To a solution of 3,5-Dibromo-pyrazin-2-ylamine (3.00 g, 11.86 mmol) in DMF(35 ml) was added triethylamine (16 ml), then tetraldstriphenylphine palladium (0) (685 mg,0.59 mmol) and copper(i) iodide (271 mg, 1.42 mmol) were added sequentially. Finallytrimethylsilylacetylene (2.0 ml, 14.3 mmol) was added dropwise. The reaction mixture wasstirred at 120 C for 30 minutes and then directly adsorbed onto silica gel. Purification byflash chromatography on silica gel with a gradient of ethyl acetate/hexane afforded the titlecompound (2.30g, 71% yield) as yellow oil. MS: m/z 270.0/272.0 [MH+].

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; SGX PHARMACEUTICALS, INC.; WO2006/15124; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common heterocyclic compound, 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, molecular formula is C6H3Br2N3, 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. 63744-22-9.

General procedure: Method F: compound 6 (2 mmol) was dissolved in MeOH, and stirred at 0 C., to which was added NaSMe (20% aq, 1.8 eq.), followed by naturally warming to room temperature, and reacting overnight, monitored by TCL until complete conversion, to which was added DCM. The system was washed with water, and the organic phase was concentrated to obtain a while solid, which was directly used for the next step reaction.

The synthetic route of 6,8-Dibromoimidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Xiamen University; Deng, Xianming; Huang, Wei; Sun, Xihuan; Zhang, Ting; He, Zhixiang; Liu, Yan; Wu, Xinrui; Zhang, Baoding; Li, Xiaoyang; Zhang, Jingfang; Chen, Yun; Li, Li; Xu, Qingyan; Hu, Zhiyu; (206 pag.)US2020/165246; (2020); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

13301-04-7, The chemical industry reduces the impact on the environment during synthesis 13301-04-7, name is Methyl 3,6-dibromopyrazine-2-carboxylate, I believe this compound will play a more active role in future production and life.

To a solution of methyl 3,6-dibromopyrazine-2-carboxylate (583 mg, 1.97 mmol), and (2,3-dichlorophenyl)boronic acid (375 mg, 1.97 mmol) in dioxane (40 ml) was added CS2CO3 (1.93 g, 5.91 mmol) in H2O (10 mL) and PdCkdppf (144 mg, 0.2 mmol). The reaction was refluxed for 20 min, allowed to cool to rt, and extracted with EtOAc. The combined organic layers were washed with brine and dried over MgS04. The mixture was concentrated under reduced pressure. Purification by flash chromatography resulted in 370 mg (52%) of the desired product. NMR (500 MHz, CDCh) delta 8.58 – 8.53 (m, 1H), 7.38 – 7.32 (m, 1H), 7.29 – 7.22 (m, 1H), 7.14 – 7.08 (m, 1H), 3.82 – 3.76 (m, 3H).

The chemical industry reduces the impact on the environment during synthesis Methyl 3,6-dibromopyrazine-2-carboxylate. I believe this compound will play a more active role in future production and life.

Reference:
Patent; REVOLUTION MEDICINES, INC.; LI, Jie Jack; KOLTUN, Elena S.; GILL, Adrian Liam; BUCKL, Andreas; WON, Walter; AAY, Naing; MELLEM, Kevin; TZITZILONIS, Christos; JOGALEKAR, Ashutosh; CREGG, James Joseph; (177 pag.)WO2019/75265; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

55557-52-3, 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. 55557-52-3 name is 3-Chloropyrazine-2-carbonitrile, 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.

(3-hydroxy-cyclobutyl) methyl benzoate (1.48g, 7.18mmol, 1.05eq.) In anhydrous THF (2mL) was added to sodium hydride(60%, 274mg, 6.84mmol, 1eq.) In anhydrous THF (30mL) suspension, and the mixture was stirred for 1h at room temperature, and then added 3-Chloro-pyrazine-2-carbonitrile (909mg, 6.84mmol, 1eq.), The reaction mixture was stirred at room temperature for 15h. The mixture was diluted with 50mL of water was added,Then EtOAc (30mL x 2) and extracted. The organic solution was washed with saturated sodium chloride combined (30mL x 2), dried over anhydrous sodium sulfate,Then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: PE / EtOAc (V / V) = 2.7 / 1) to give the title compound as a white solid (1g, 28%).

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

Reference:
Patent; East Sunshine Pharmaceutical Co., Ltd. of Guangdong; Ren, Qingyun; Luo, Huichao; Tang, Changhua; Zhang, Jiancun; Zhang, Yingjun; (30 pag.)CN104447583; (2016); B;,
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. 33332-29-5

compound 5-a (2.6g, 20mmol), 2- bromo-1,1-diethoxyethane (12.0g, 60.89mmol) was dissolved in 30ml isopropanol was then added a solution of hydrogen bromide (10.5g, 62.22mmol), 80 deg. C stirred overnight. Completion of the reaction, cooled to room temperature, adjusted to pH 8 sodium hydrogen carbonate, extracted with dichloromethane, the combined organic phases separated, concentrated under reduced pressure to give a crude product which, by Combi-flash chromatography [DCM: MeOH = 90: 10 ~ 70: 30 ] to give a brown solid compound 16-b (2.3g), was used directly in the next reaction. Yield: 49.75%, purity 96.63%.

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; Shanghai Haiyan Pharmaceutical Technology Co. Ltd; Yangtze River Pharmaceutical Group Co., Ltd; Jin, Yunzhou; Bo, Ping; He, Qi; Lan, Jiong; Zhou, Fusheng; Zhang, Liang; He, Xiangyu; (59 pag.)CN105524068; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, A common compound: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

To the reaction flask was added tetrahydrofuran (50 ml). trimethylsilylacetylene (580 mg, 5.9 mmol), triethylamine (1.2 g, 11.8 mmol), CuI (0.1 g), Pd(PPh3)4 (0.1 g) and the compound 3,5-dibromo-2-aminopyrazine 1a (1.0 g, 3.95 mmol) were reacted under nitrogen for 3 hours at room temperature.TLC showed the reaction was completed, 50ml of water was added and extracted with ethyl acetate (30mL) twice the aqueous phase, the organic phases are combined,Once, dried over anhydrous sodium sulfate washed with brine, and dried to give the crude product under reduced pressure using a rotary evaporator,Through the column to give the crude title compound 5a (0.5g, 18.5mmol), a yield of 47.1%

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-Amino-3,5-dibromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Shanghai Huahuituo Pharmaceutical Technology Co., Ltd.; Zhejiang Huahai Pharmaceutical Co., Ltd.; Xu Xin; Zhang Tian; Li Yunfei; Wang Guan; Zhu Weibo; Li Qiang; Qu Minkai; Zhang Linli; Song Jinqian; Liu Lei; Chen Haiji; Liu Qiang; Wang Yijin; Ge Jian; (67 pag.)CN109535164; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

356783-16-9, 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. 356783-16-9, name is 3,6-Dichloropyrazine-2-carbonitrile belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

REFERENTIAL EXAMPLE II-11 In 15 ml of dimethylformamide was dissolved 1.5 g of 3,6-dichloro-2-pyrazinecarbonitrile. After adding 1.2 g of 4-methoxyphenol and 1.8 g of potassium carbonate, the mixture thus obtained was stirred at room temperature for 30 minutes. A mixture of 20 mL of ethyl acetate and 60 mL of water was added to the reaction mixture, and the organic layer was separated. The organic layer was washed successively with water and saturated aqueous solution of sodium chloride and dried on anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [eluent: n-hexane:ethyl acetate=5:1] to obtain 2.1 g of 6-chloro-3-(4-methoxyphenoxy)-2-pyrazinecarbonitrile as a yellow-colored solid product. R (KBr) cm-1: 2236 H-NMR (CDCl3) delta: 3.83(3H,s), 6.95(2H,d,J=9.2 Hz), 7.11(2H,d,J=9.2 Hz), 8.26(1H,s)

The synthetic route of 356783-16-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Toyama Chemical Co., Ltd.; US2003/130213; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem