Month: July 2021

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. 313339-92-3, name is 3,5-Dichloropyrazine-2-carbonitrile, A new synthetic method of this compound is introduced below., Recommanded Product: 313339-92-3

Step 1: To a mixture of 3,5-dichloropyrazine-2-carbonitrile (369 mg, 2.09 mmol) and tert-butyl (3R,4R)-4-aminotetrahydro-2H-pyran-3-ylcarbamate (500 mg, 2.3 mmol) in AcCN (7.5 mL) was added DIPEA (0.41 mL, 2.3 mmol). After stirring at room temperature for 5 h, it was diluted with EtOAc, washed with sat. NaHCO3, organic layer was separated and washed with brine, dried and concentrated to give tert-butyl (3R,4R)-4-(6-chloro-5-cyanopyrazin-2-ylamino)tetrahydro-2H-pyran-3-ylcarbamate (880 mg).

The synthetic route of 313339-92-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Portola Pharmaceuticals, Inc.; Song, Yonghong; Xu, Qing; Jia, Zhaozhong J.; Kane, Brian; Bauer, Shawn M.; Pandey, Anjali; US2013/131040; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 54608-52-5, name is 2-Hydrazinopyrazine, This compound has unique chemical properties. The synthetic route is as follows., Recommanded Product: 54608-52-5

General procedure: The desired compounds 1a-g and 2a-f were prepared by reaction between pyridoxal hydrochloride (0.15 g, 0.74mmol) and the appropriate aromatic or heteroaromatic hydrazine or N-acylhydrazine (1.1 eq., 0.81mmol) in ethanol (10.0 mL). The reaction mixture was stirred for 1-48 hours at room temperature. After that, product was purified by wash-ing with cold ethanol (3.0 mL) and cold diethyl ether (3.0 mL), leading to the pure derivatives 1a-g and 2a-f as solid in 42-86% yields.

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 54608-52-5.

Reference:
Article; Nogueira, Thais Cristina Mendonca; Cruz, Lucas Dos Santos; Lourenco, Maria Cristina; de Souza, Marcus Vinicius Nora; Letters in drug design and discovery; vol. 16; 7; (2019); p. 792 – 798;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 5521-55-1, 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. 5521-55-1 name is 5-Methylpyrazine-2-carboxylic acid, 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: To a solution of 2-methylpyrazine-5-carboxylic acid (10 g, 72.4 mmol) and TEA (20 mL, 108 mmol) in t-butanol (156 mL) and dioxanes (100 mL) was added diphenyl phosphorylazide (23.4 mL, 108 mmol) and the resulting solution was warmed at 100 C. for 3 hours and then cooled to room temperature overnight. The crude reaction mixture was concentrated in vacuo. Purification by chromatography (silica 0-15% ethyl acetate/hexanes) following trituration of impure fractions with ether afforded (5-methyl-pyrazin-2-yl)-carbamic acid tert-butyl ester (10.6 g, 70%): 1H NMR (300 MHz, CHLOROFORM-d) delta ppm 1.56 (s, 9H) 2.51 (s, 3H) 8.02 (br. s., 1H) 8.07-8.14 (m, 1H) 9.18 (d, J=1.13 Hz, 1H).

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

Reference:
Patent; Brotherton-Pleiss, Christine E.; Walker, Keith A. M.; US2012/149718; (2012); A1;,
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, Safety of (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine

Into a 500-mL 3-necked round-bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed (2 S)-3 , 6-dimethoxy-2-(propan-2-yl)-2, 5 -dihydropyrazine (3 g, 15.47 mmol) and THF (200 mL). A solution of n-BuLi in n-hexane (2.5 M) (9.8 mL, 24.5 mmol) was added at -80 °C in a liquid nitrogen bath. The resulting solution was stirred for 30 mm at -80°C in a liquid nitrogen bath. Then a solution of 5-(bromomethyl)-2,4-dichloropyridine (4.7 g, 18.53 mmol) in THF (lOmL) was added. The resulting solution was allowed to react, with stirring, for an additional 1 h while the temperature was maintained at -80°C in a liquid nitrogen bath. The reaction was then quenched by the addition of 120 mL of ammonium chloride (sat. aq.). The resulting mixture was extracted with DCM (2 x 150 mL) and the organic layers were combined, dried over anhydrous sodium sulfate, filtered and concentrated under vacuum. The residue was purified by silica gel chromatography (eluting with 1:10 ethyl acetate/pet. ether) to afford (2R,5S)- 2- [(4,6-dichloropyridin-3 -yl)methyl]-3 , 6-dimethoxy-5 -(propan-2-yl)-2, 5 -dihydropyrazine as a white solid. MS: (ESI, m/z): 344, 346 [M+H]t

At the same time, in my other blogs, there are other synthetic methods of this type of compound, (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, and friends who are interested can also refer to it.

Reference:
Patent; FORMA THERAPEUTICS, INC.; ZABLOCKI, Mary-Margaret; GUERIN, David J.; NG, Pui Yee; WANG, Zhongguo; SHELEKHIN, Tatiana; CARAVELLA, Justin; LI, Hongbin; IOANNIDIS, Stephanos; (518 pag.)WO2019/32863; (2019); 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. 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, A new synthetic method of this compound is introduced below., COA of Formula: C5H2ClN3

A mixture of the respective boronic acid derivative (B-B(OH)2) (21.5 mmol), 3-chloro-pyrazine-2-carbonitrile (21.5 mmol), a solution of K2CO3 (59.4 mmol) in water (30 mL), PPh3 (3. 2 mmol), Pd(OAc)2 (1.05 mmol) in dry DME was stirred at reflux under inert atmosphere for 16 h. After cooling to rt, the reaction mixture was diluted with EtOAc, filtered over celite, the filtrate was dried over MgSO4, filtered and concentrated in vacuo to yield the desired pyrazine-2-carbonitrile derivative which was used for the next step without further purification prepared by reaction with commercially available 3-m-tolyl-boronic acid LC-MS: tR=0.88 min; [M+H+ MeCN]+=243.63

The synthetic route of 55557-52-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Aissaoui, Hamed; Boss, Christoph; Hazemann, Julien; Koberstein, Ralf; Siegrist, Romain; Sifferlen, Thierry; US2011/105491; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 19847-12-2, 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. 19847-12-2, name is Pyrazinecarbonitrile, This compound has unique chemical properties. The synthetic route is as follows.

Step 6 C-Pyrazin-2-yl-methylamine Pyrazine-2-carbonitrile 1g (10.5 g, 100 mmol) was dissolved in 150 mL of 1,4-dioxane, then Raney nickel (1.0 g) was added into a 250 mL autoclave. The reaction mixture was reacted in hydrogen atmosphere for 8 hours under 40 atmosphere at 60 C and filtered and concentrated under reduced pressure to obtain the title compound C-pyrazin-2-yl-methyl amine 1h (10.7 g, yield 98%) as a brown oil. MS m/z (ESI): 110 [M+1].

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

Reference:
Patent; Jiangsu Hengrui Medicine Co., Ltd.; Shanghai Hengrui Pharmaceutical Co. Ltd.; EP2404921; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 113305-94-5, name is 5-Aminopyrazine-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. Formula: C5H4N4

To a suspension of 5-aminopyrazine-2-carbonitrile (211 mg, 1.74 mmol) in THF (10 mL) was added sodium hydride (116 mg, 2.90 mmol) at 0 C and stirred at ambient temperature for 1 h. Compound 305-7 (500 mg, 1.45 mmol) was added and stirred at 55 C for 2 h. After cooling to ambient temperature, the reaction mixture was quenched with ice-water and extracted with ethyl acetate. The organic layer was washed with water and brine, dried over Na2SO4 and concentrated. The crude product was purified by column chromatography (hexanes/ethyl acetate: 5/1) to afford the title compound 306-7 as a yellow solid (253 mg, 42 % yield).

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

Reference:
Patent; PHARMAENGINE, INC.; CAI, Xiong; QIAN, Changgeng; WANG, Yanong Daniel; (98 pag.)WO2017/132928; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 59489-71-3, 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. 59489-71-3, name is 2-Amino-5-bromopyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Into a 20-L 4-necked round-bottom flask was placed a solution of 5-bromopyrazin-2-amine (400 g, 2.30 mol) in ethylene glycol dimethyl ether (8 L) , iodocopper (131 g, 687.84 mmol) , diiodane (293 g, 1.15 mol) , iodopotassium (380 g, 2.29 mol) and 3-methylbutyl nitrite (1800 mL, 11.5 mol) . The resulting solution was stirred for 30 min at 60 C, then extracted with 2 x 10 L of ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate and concentrated under vacuum to afford 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-bromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DEBENHAM, John S.; COX, Jason M.; LAN, Ping; SUN, Zhongxiang; FENG, Zhe; SUN, Chunrui; SEGANISH, W. Michael; LAI, Zhong; ZHU, Chen; BARA, Thomas; RAJAGOPANALAN, Murali; DANG, Qun; KIM, Hyunjin M.; HU, Bin; HAO, Jinglai; (112 pag.)WO2018/107415; (2018); 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 6863-73-6 as follows. Recommanded Product: 6863-73-6

[0665] A 3-necked 250 mL round-bottomed flask was charged with cesium carbonate (22.64 g, 69.5 mmol), 2-amino-3-chloropyrazine (3 g, 23.16 mmol, Synchem Inc., Elk Grove Village, IL), and {1,1′-bis(diphenylphosphino)ferrocene} dichloropalladium(II) (1.69 g, 2.32 mmol, Strem Chemicals, Newburyport, MA). A reflux condenser was attached, and the apparatus was sealed. The vessel was evacuated and backfilled with nitrogen. DMF (66.2 mL) was added, followed by triethylborane (1.0 M in THF; 42 mL, 42 mmol; Sigma-Aldrich Corporation, St. Louis, MO, USA). The reaction was then stirred in a pre-heated 90 C oil bath for 1 h. The reaction mixture was cooled to rt, water was added, and the resulting mixture was extracted with DCM (2). The combined extracts were dried over MgSO4 and concentrated in vacuo. The crude residue was taken up in MeOH and loaded onto a column composed of Si- propylsulfonic acid (Silicyle). The column was flushed with 4 column volumes of MeOH before eluting the title compound with 4 column volumes of 2M ammonia in MeOH. The filtrate was concentrated in vacuo, and the residue was purified by silica gel chromatography (eluent: 0-20% 2 M NH3 in MeOH/DCM) to provide 3-ethylpyrazin-2-amine (Intermediate I- 19, 2.34 g, 19.0 mmol, 82 % yield) as a brown oil. 1H NMR (400 MHz, DMSO-d6) d ppm 7.75 (d, J=2.70 Hz, 1H) 7.65 (d, J=2.70 Hz, 1H) 6.13 (br s, 2 H) 2.60 (q, J=7.39 Hz, 2 H) 1.17 (t, J=7.46 Hz, 3 H).

According to the analysis of related databases, 6863-73-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; AMGEN INC.; ALLEN, John Gordon; ALLEN, Jennifer Rebecca; MINATTI, Ana Elena; XUE, Qiufen; WURZ, Ryan Paul; TEGLEY, Christopher M.; PICKRELL, Alexander J.; NGUYEN, Thomas T.; MA, Vu Van; LOPEZ, Patricia; LIU, Longbin; KOPECKY, David John; FROHN, Michael J.; CHEN, Ning; CHEN, Jian Jeffrey; SIEGMUND, Aaron C.; AMEGADZIE, Albert; TAMAYO, Nuria A.; BOOKER, Shon; GOODMAN, Clifford; WALTON, Mary; NISHIMURA, Nobuko; SHIN, Youngsook; LOW, Jonathan D.; CEE, Victor J.; REED, Anthony B.; WANG, Hui-Ling; LANMAN, Brian Alan; (738 pag.)WO2019/213516; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 486460-21-3,Some common heterocyclic compound, 486460-21-3, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine, molecular formula is C6H7F3N4, 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.

Dichloromethane (100 ml) and the keto acid compound (10.0 g, 43.07 mmol) prepared in Example 8 were added to a 250 ml three-necked flask, and dissolved by stirring. Oxalyl chloride (6.56 g, 51.68 mmol) was added dropwise at 10 to 15 C, and the dropwise addition was completed, and the mixture was heated to 30 to 35 C to stir the reaction. The reaction was completed, and concentrated under reduced pressure at 30 to 40 C to dryness to pale-yellow liquid (10.91 g, 43.64 mmol), methylene chloride (100 ml), triethylamine (5.79 g, 57.24 mmol) and the above yellow liquid (10.0 g, 52.04 mmol) was dissolved by stirring. The solution of the free base (13.0 g, 52.04 mmol) / dichloromethane (20 ml) of the compound of the formula a was added dropwise to 0 to 5 C, and the dropwise addition was completed. After the completion of the dropwise addition, the mixture was heated to 10 to 15 C to stir the reaction. The reaction was completed, water was added and stirred. Layering, taking the lower organic phase and discarding the upper aqueous phase. The organic phase was washed with a 5% aqueous solution of sodium chloride and concentrated to dryness to dryness to dryness to afford white solid (19.24 g, 47.36 mmol) as a ketoamide compound in a molar yield of 91%.

The synthetic route of 486460-21-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Zhejiang Ruibo Pharmaceutical Co., Ltd.; Gao Zhaobo; Zhang Xianyi; He Zhi; Mei Yijiang; Zheng Hui; (9 pag.)CN109956865; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem