Pyrazines

Electric Literature 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.

3,5-dibromo-pyrazin-2-ylamine (10.4g, 41.12 mmol), and bromoacetaldehyde diethyl acetal (9.8 ml, 62.51mmol) then dissolved in a mixed solvent of tetrahydrofuran (14 ml) and distilled water (140 ml), and the mixture was stirred for 4 hours at 120C , in addition stirred at room temperature for 12 hours to.Saturated aqueous sodium hydrogen carbonate solution to the reaction solution was neutralized by addition.The resulting solid was filtered, washed with distilled water and dried to give the title compound (8.7g, 76%).

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; HANMI PHARM. CO., LTD.; HAM, YOUNG JIN; SON, JUNG BEOM; PARK, CHANG HEE; KANG, SEOK JONG; CHOI, JAE YUL; KIM, SEO HEE; (36 pag.)KR2015/113801; (2015); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 78342-42-4, These common heterocyclic compound, 78342-42-4, name is (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, 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.

Into two 250-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 (2 g, 10.86 mmol) and THF (15 mL). This was followed by the addition of butyllithium (2.5 M) (6.5 mL, 16.25 mmol) at -78 °C. The resulting solution was stirred for 30 mm. To this was added 3- (bromomethyl)-2,6-dichloropyridine (2.62 g, 10.88 mmol). The resulting solution was stirred for an additional 1 h at -78°C. The reaction was then quenched by the addition of 5 mL of NH4HCO3 (saturated) and the mixture was diluted with 10 mL of H20. The resulting mixture of two batches was combined and extracted with 3 x 50 mL of ethyl acetate. 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 1/5 ethyl acetate/pet. ether) to afford (2R,5S)-2-((2,6-dichloropyridin-3 -yl)methyl)-5 -i sopropyl-3 , 6-dimethoxy-2, 5 -dihydropyrazine as a colorless oil. MS: (ESI, m/z): 344, 346 [M+H]t

Statistics shows that (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine is playing an increasingly important role. we look forward to future research findings about 78342-42-4.

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

Electric Literature of 126069-70-3,Some common heterocyclic compound, 126069-70-3, name is 2-(Trifluoromethyl)-5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine, molecular formula is C7H8F3N3, 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 a solution of 1.0 g (5.23 mmol) 2- (TRIFLUOROMETHYL)-5, 6,7, 8- tetrahydroimidazo [1, 2-a] pyrazine (Step A) in 50 mL of dichloromethane at 0 C was added N, N- diisopropylethylamine (0.910 mL, 5.23 mmol) and di-tert-butyl dicarbonate (1.14 g, 5.24 mmol). After the reaction was stirred at 0 C for 5 min, the reaction was warmed to ambient temperature and continued to stir for 4 h. The reaction mixture was partitioned between ethyl acetate and 0. 5N hydrochloric acid. The aqueous phase was extracted with three potions of ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, and concentrated. The residue was purified by flash chromatography using a BIOTAGE system (silica gel, 50% ethyl acetate in hexanes then 100% ethyl acetate) to give the title compound as a solid. LC/MS 236 (M+1-56).

The synthetic route of 126069-70-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK & CO., INC.; WO2004/58266; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 14508-49-7, 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. 14508-49-7, name is 2-Chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows.

The mixture of 2-chloropyrazine (7) (20.0 g, 0.175 mol),hydrazine hydrate (60 mL) and sodium carbonate (27.84 g,0.264 mol) was stirred for 2 h at 120-130 C. After completionof the reaction that was checked by TLC, the reactionmass was allowed to cool at 50-60 C and then water(60.0 mL) followed by isopropyl alcohol (IPA) (40.0 mL)were added. The reaction mass was maintained for 16 h at 0-3 C and then the precipitated white solid was separatedby filtration. The wet solid was dried under vacuum at 45-50 C to obtain desired 2-hydrazinopyrazine (14.8 g, 77.8%).1H NMR (400 MHz; CD3OD), d, ppm (J, Hz): 7.94-8.14(2H, m, Ar-H); 7.69 (1H, s, Ar-H). ESI-MS m/z (rel, %):111.07 (M+H+) (100). HRMS (FAB) Calc.: C4H6N4:110.059246; Found: 111.0592 [M+H+].

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

Reference:
Article; Mannam, Madhava Rao; Devineni, Subba Rao; Pavuluri, Chandra Mouli; Chamarthi, Naga Raju; Kottapalli, Raja Sekhara P.; Phosphorus, Sulfur and Silicon and the Related Elements; vol. 194; 9; (2019); p. 922 – 932;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 486460-20-2, A common heterocyclic compound, 486460-20-2, name is 3-(Trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyrazine, molecular formula is C6H3F3N4, 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.

To a solution of 3-(trifluoromethyl)-[l ,2,4]triazolo[4,3-a]pyrazine ( 1 .60 g) in metanol(20 mL) was added a catalytic amount of Pd/C. The suspension was stirred under H2 for 5 h, and then filtered. The filtrate was concentrated in vacuo to give a residue, which was used for next step without further purification.

The synthetic route of 486460-20-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SUNSHINE LAKE PHARMA CO., LTD.; ZHANG, Jiancun; ZHANG, Yingjun; ZHANG, Weihong; LIU, Bing; ZHANG, Jiquan; LIU, Jinlei; ZHANG, Lu; WO2013/71697; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 17231-51-5, name is 3-Amino-6-bromopyrazine-2-carbonitrile, 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 17231-51-5, category: Pyrazines

Step 2: synthesis of 3,6-dibromopyrazine-2-carbonitrile (15)To a solution of copper(ii) bromide (1.432 g, 6.41 mmol) and tert-butylnitrite (0.769 mL, 6.41 mmol) in acetonitrile (40 mL) was added 3-amino-6-bromopyrazine-2- carbonitrile 14 (1.16 g, 5.83 mmol) in portions (in 2h). The reaction was stirred for 2h at 50C. Quenched with 2N HC1 solution and the resulting precipitate was collected. Purification by chromatography (CH2CI2) gave pure 3,6-dibromopyrazine-2- carbonitrile 15 (820 mg, 53.5 %). 1H-NMR (400 MHz, CDC13) 8.66 (s, 1H). (m/z) = 261, 263 and 265 (M+H)+.

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; N.V. ORGANON; FOLMER, Brigitte, Johanna, Bernita; MAN, de, Adrianus, Petrus, Antonius; GERNETTE, Elisabeth, Sophia; CORTE REAL GONCALVES AZEVEDO, Rita; IBRAHIM, Hemen; WO2011/147764; (2011); 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. 1260812-97-2, name is 2-Bromo-3-methyl-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., Recommanded Product: 1260812-97-2

0 C,N-iodosuccinimide (2.60 g, 11.00 mmol)Bromo-3-methyl-5H-pyrrolo [2,3-b] pyrazine (2.05 g, 7.25 mmol)In acetone (30 mL)The reaction was stirred at room temperature for 3 h.The solvent was removed under reduced pressure, water (30 mL) and dichloromethane (30 mL) were added to the residue, the solid was filtered, the solid was washed with a little water and dichloromethane,The brown solid was dried in vacuo at 60 C to give 2.50 g of a brown solid,The crude product was used without further purification for the next step.

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

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. 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Quality Control of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride

General procedure: A solution of 3-(trifluoromethyl)-5,6,7,8-tetrahydro [1,2,4]triazolo[4,3-a]pyrazine hydrochloride salt (1.0 eq.) in dimethylformamide(DMF, 2-3 mL)was added potassium carbonate (2.5eq.) at and stirred for 15 min at room temperature. To this, N-(benzo[d]thiazol-2-yl)-2-chloroacetamide derivatives (1.0 eq.) in DMF was added to the reaction mixture at room temperature. The resulting reaction mixturewas heated at 70 C for 18 h. The completion of the reaction was monitored on TLC (using 10% MeOH: DCM and ammonia as a modifier as mobile phase) which confirmed that the reaction got completed after 18 h. The reaction mixture was pouredinto ice-cold water and extracted with ethyl acetate (2 x 30 mL).Organic layers were combined and the combined organic layer was dried over sodium sulfate and concentrated under reduced pressure to afford crude desired product and crystallized it from methanol to get N-(benzo[d]thiazol-2-yl)-2-(3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazolo [4,3-a]pyrazin-7 (8H)-yl)acetamide derivatives(12a-12e) in good practical yield.

The synthetic route of 762240-92-6 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Jethava, Divya J.; Acharya, Prachi T.; Vasava, Mahesh S.; Bhoi, Manoj N.; Bhavsar, Zeel A.; Rathwa, Sanjay K.; Rajani, Dhanji P.; Patel, Hitesh D.; Journal of Molecular Structure; vol. 1184; (2019); p. 168 – 192;,
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 36070-80-1 as follows. Application In Synthesis of 5-Chloropyrazine-2-carboxylic acid

To a solution of 5-chloropyrazine-2-carboxylic acid (500 mg, 3.1 mmol) and methyl-6- aminohexanoate hydrochloride (688 mg, 3.71 mmol) in dichloromethane (15 mL) was added 1 -ethyl-3-(3-dimethylaminopropyl)carbodiimide (71 1 mg, 3.71 mmol, 1.2 equiv). The reaction was allowed to stir for 18 hours at room temperature and was then diluted with dichloromethane (75 mL) and washed with 1 N hydrochloric acid (15 mL). The layers were separated, and the organic layer was washed with brine, dried over anhydrous sodium sulfate, filtered, concentrated in vacuo and the residue was purified by flash column chromatography over silica gel (gradient elution with 20%-70% ethyl acetate in heptane) to provide methyl 6-{[(5-chloropyrazin-2-yl)carbonyl]- amino}hexanoate, 20 (378 mg, 43%), as a white solid. LCMS (Protocol E): m/z 308.2

According to the analysis of related databases, 36070-80-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PFIZER INC.; DUSHIN, Russell George; ABRAMITE, Joseph A.; CASAVANT, Jeffrey M.; CHE, Ye; FILZEN, Gary Frederick; FLANAGAN, Mark Edward; GILBERT, Adam Matthew; MOINE, Ludivine; O’DONNELL, Christopher John; ROBERTS, Lee; STARR, Jeremy; TUMEY, Lawrence N.; UCCELLO, Daniel P.; YOUNG, Jennifer; (135 pag.)WO2018/25168; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 446286-94-8, 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. 446286-94-8, name is 5-Bromo-N,N-dimethylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To asolution of dimethyl amino 3d (1370 mg, 6.82mmol) in drytetrahydrofuran (50 mL) under Ar at 80 C was slowly added1.57M n-butyllithium hydride (n-BuLi) in hexane (10.8 mL).After stirring for 60min at 80 C, to the mixture was addedN,N-dimethylformamide (DMF) (2.0 mL, 26mmol) and theresulting solution was allowed to warm to r.t. After stirring for1 h, to the reaction mixture was added water to decompose theexcess reducing agent. Further, to the mixed solution was addedwater followed by extraction with ethyl acetate (3 200 mL).The combined organic layers were dried over Na2SO4, filtered,and the solvents were removed under reduced pressure. Theresidue obtained was purified by silica gel column chromatography(hexane/ethyl acetate = 1/1) to yield arylaldehyde 4d (975 mg, 6.46mmol, 95%) as a light yellow solid: mp 112 C;IR (neat, , cm1): 2783, 1681, 1373, 1008; 1HNMR (500MHz, CDCl3) 9.91 (s, 1H), 8.69 (s, 1H), 8.08 (d, J = 1.1 Hz,1H), 3.26 (s, 6H); 13CNMR (126 MHz, CDCl3) 190.7, 155.5,144.3, 136.8, 129.4, 37.9; HR-ESI-MS: m/z: [M+ H]+ calculatedfor C7H10N3O, 152.0824; found, 152.0814.

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-Bromo-N,N-dimethylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Saito, Ryohei; Kuchimaru, Takahiro; Higashi, Shoko; Lu, Shijia W.; Kiyama, Masahiro; Iwano, Satoshi; Obata, Rika; Hirano, Takashi; Kizaka-Kondoh, Shinae; Maki, Shojiro A.; Bulletin of the Chemical Society of Japan; vol. 92; 3; (2019); p. 608 – 618;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem