Pyrazines

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. 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, A new synthetic method of this compound is introduced below., Application In Synthesis of 2-Chloro-3-hydrazinylpyrazine

A 500 mL round bottom flask was charged with 2-chloro-3-hydrazinylpyrazine (5.0 g, 35 mmol) and THF (100 mL). To the above solution was added dropwise a solution of trifluoroacetic anhydride (9.6 g, 45.6 mmol) in THF (125 mL). The resulting solution was stirred for 1 h at 0 C. Reaction progress was monitored by TLC (EtO Ac/petroleum ether = 1 :2). Work-up: the reaction mixture was diluted with water and then extracted with CH2CI2 (50 mL x 3). The combined organic layers were washed with brine (40 mL), dried over anhydrous Na2S04 and concentrated in vacuo, to afford 7.56 g (87%) of the product as a yellow solid.

The synthetic route of 63286-28-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; KALYPSYS, INC.; BORCHARDT, Allen; DAVIS, Robert; NOBLE, Stewart, A.; WO2011/112766; (2011); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 14508-49-7,Some common heterocyclic compound, 14508-49-7, name is 2-Chloropyrazine, molecular formula is C4H3ClN2, 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.

b) 2 4-Methylpiperazin-1-yl)-/V-pyrazin-2-yl-2,4′-bipyridin-6-amine; An oven dried resealable Schlenk tube was charged with 2′-(4-methylpiperazin-1-yl)- 2,4′-bipyridin-6-amine (example 34a, 0.09 g, 0.33 mmol), 2-chloropyrazine (0.04 mu, 0.39 mmol), sodium terf-butoxide (0.04 g, 0.38 mmol) and dioxane (1 ml_). The Schlenk tube was subjected to three cycles of evacuation-backfilling with argon, and tris(dibenzylideneacetone)dipalladium(0) (0.01 g, catalytic amount) and 4,5- bis(diphenylphosphino)-9,9-dimethylxanthene (0.01 g, catalytic amount) were added. After three further cycles of evacuation-backfilling with argon, the Schlenk tube was capped and placed in an oil bath at 95 C. After 16h, the mixture was cooled and the solvent was removed in vacuo. The residue was purified by flash chromatography to give the title compound (0.09 g, 82%) as a solid.LRMS (m/z): 348 (M+1)+.1 H NMR (500 MHz, CHLOROFORM-d) delta ppm 2.35 (s, 3 H) 2.53 – 2.55 (m, 4 H) 3.63 – 3.66 (m, 4 H) 7.16 (dd, =6.50, 2 Hz, 1 H) 7.34 (s, 1 H) 7.39 (d, J=9.00 Hz, 1 H) 7.61 (d, J=10.00 Hz, 1 H) 7.73 (t, J=10.00 Hz, 1 H) 7.96 (br. s., 1 H) 8.13 (d, J=3.50 Hz, 1 H) 8.19 – 8.21 (m, 1 H) 8.13 (d, J=3.50 Hz, 1 H) 8.98 (d, J=2.00 Hz, 1 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-Chloropyrazine, its application will become more common.

Reference:
Patent; ALMIRALL, S.A.; VIDAL JUAN, Bernat; FORNS BERENGUEL, Maria Pilar; CASTILLO MCQUADE, Marcos; ERRA SOLA, Montserrat; MIR CEPEDA, Marta; WO2012/41476; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 91476-80-1, 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. 91476-80-1 name is 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine, 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.

Compound 2A (126.0mg, 0.48mmol) was dissolved in 10.0ml acetonitrile, Ar gas protection. Compound 3a-1 (118.0mg, 0.96mmol), and lithium perchlorate (102.0mg, 0.96mmol), the reaction mixture was heated to 80 deg. C, the reaction after 20 hours, cooled to room temperature.The reaction mixture was evaporated to dryness and the residue with CH2Cl2Dissolved, the organic phase was washed 3 times with saturated NaCl solution, dried over anhydrous Na2SO4Dried, filtered, and evaporated to dryness and the residue was separated by column chromatography (dichloromethane: methanol = 100: 1-50: 1), to give a compound 80.8mg as a white solid, mp: 86-88 deg. C, a yield of 45.0%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine, and friends who are interested can also refer to it.

Reference:
Patent; Chinese Academy of Sciences, Shanghai Institute of Medicine; Nanjing Changao Pharmaceutical Technology co., LTD; YANG, YU SHE; CAO, XU FENG; LI, ZHAN; LI, WEI; (78 pag.)CN103965194; (2016); B;,
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. 6863-74-7, name is 6-Chloropyrazine-2-carbonitrile, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C5H2ClN3

c) Preparation of N-(6-chloro-pyrazin-2-ylmethyl)-2,2-dimethyl-propionamideThe preceding intermediate (8.8 g, 62.8 mmol) was hydrogenated under standard conditions in ethanol (75 mL) and in the presence of Raney nickel (3.6 g, 62.8 mmol), as well as di-tert-butyldicarbonate (14.4 g, 66 mmol) over 18 h. The catalyst was filtered off over Celite, the filtrated was concentrated in vacuo and chromatographed over silica gel to afford the desired Boc-protected amine (6.7 g, 27.6 mmol, 63%)

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 6863-74-7.

Reference:
Patent; BASF SE; WO2009/112523; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 1196151-53-7, These common heterocyclic compound, 1196151-53-7, name is 6-Bromopyrazine-2-carboxylic acid, 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.

A mixture of 6-bromopyrazine-2-carboxylic acid (404 mg, 1.99 mmol), 2-(4- fluorophenyl)-N-methyl-6-(N-methylmethylsulfonamido)-5-(4,4,5,5-tetramethyl-l,3,2- dioxaborolan-2-yl)benzofuran-3-carboxamide (1 g, 1.99 mmol), 2M sodium carbonate (4 ml, 8 mmol), Bis(triphenylphosphine)palladium(II) dichloride (70 mg, 0.1 mmol) was suspended in DME (7 ml), DMF (2 ml), water (3 ml) and EtOH (2 ml) in a sealed tube and heated in a microwave oven at 120C for 20 min.. Then concentrated under vacuum, applied onto Prep HPLC and eluted with H20 (0.1%TFA) and Acetonitrile(0.1%TFA). This resulted in 0.96g (95 %) of 6-(2-(4-fluorophenyl)-3-(methylcarbamoyl)-6-(N- methylmethylsulfonamido)benzofuran-5-yl)pyrazine-2-carboxylic acid as a white solid. LC-MS (ES, m/z) C23H19FN406S: 498; Found: 499 [M+H]+.

The synthetic route of 1196151-53-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; MCCOMAS, Casey Cameron; LIVERTON, Nigel J.; HABERMANN, Joerg; KOCH, Uwe; NARJES, Frank; LI, Peng; PENG, Xuanjia; SOLL, Richard; WU, Hao; PALANI, Anandan; DAI, Xing; LIU, Hong; HE, Shuwen; LAI, Zhong; DANG, Qung; ZORN, Nicholas; WO2013/34047; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 243472-70-0,Some common heterocyclic compound, 243472-70-0, name is 5-Bromo-2,3-diphenylpyrazine, molecular formula is C16H11BrN2, 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 mixture of 5- bromo-2,3-diphenylpyrazine (1 g, 3.21 mmol) and 4-(isopropylamino)butan-1 -ol (2.32 g, 17.7 mmol) was added potassium iodide (266 mg, 1 .6 mmol). The mixture was stirred in a pressure vessel at 140C for 2 days. The reaction mixture was cooled to room temp and diluted with water. The mixture was extracted with EtOAc (x4) and the combined organic layers washed with brine, dried over Na2S04, filtered and concentrated. The crude residue was purified with column chromatography eluting with 0-2% MeOH in DCM. The fractions of the desired product were combined, concentrated, and dried under reduced pressure to obtain a brown oil (0.82 g, 71 %). 1 H NMR (400 MHz, Chloroform-d) d 8.02 (s, 1 H), 7.49 – 7.42 (m, 2H), 7.39 – 7.33 (m, 2H), 7.29 – 7.21 (m, 6H), 4.78 (p, J = 6.7 Hz, 1 H), 3.68 (t, J = 6.4 Hz, 2H), 3.43 (dd, J = 9.2, 6.7 Hz, 2H), 1.76 (qd, J = 7.8, 7.1 , 3.9 Hz, 2H), 1.65 (q, J = (0159) 6.8 Hz, 2H), 1.28 (d, J = 6.7 Hz, 6H).

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

Reference:
Patent; THE REGENTS OF THE UNIVERSITY OF MICHIGAN; HOLINSTAT, Michael; ADILI, Reheman; WHITE, Andrew; (43 pag.)WO2019/204447; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

21279-62-9, name is 3-Chloropyrazine-2-carboxamide, 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. Safety of 3-Chloropyrazine-2-carboxamide

General procedure: The starting compound (1.27 mmol) was treated with 18 aliphatic amines, alicyclic amines or saturated heterocycles containing at least one nitrogen atom (2.54 mmol). Four reactions were completed by conventional heating methods. The conditions were 110 C, toluene as a solvent and pyridine (1.27 mmol) as a base. The reaction time was set to one hour. Then the reactions were completed using the microwave reactor with focused field and conditions used for syntheses were 140 C, 30 min,120 W, methanol used as a solvent and pyridine (1.27 mmol) as a base. They were set experimentally with respect to prior experience. The progress of reaction was monitored with TLC in system hexane/ethyl acetate (1:1). Then the mixture was separated by flash column chromatograph using gradient elution. Mobile phases were hexane and ethyl acetate again.

The synthetic route of 21279-62-9 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Jandourek, Ondrej; Dolezal, Martin; Kunes, Jiri; Kubicek, Vladimir; Paterova, Pavla; Pesko, Matus; Buchta, Vladimir; Kralova, Katarina; Zitko, Jan; Molecules; vol. 19; 7; (2014); p. 9318 – 9338;,
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 912773-21-8 as follows. Recommanded Product: 912773-21-8

2-chloro-5-bromopyrazine (4.0 mmol) in CHC13 (40 mL), stirring under nitrogen, BPO (0.08 mmol) and NBS (4.4 mmol) were added to the reaction mixture, heated to reflux for 5 h, cooled . The solvent was distilled off under reduced pressure to give a crude product. A solution of morpholine (0.50 mol) in ethanol was added to the crude product of the previous step under nitrogen and stirred at room temperature overnight.The solvent was removed under reduced pressure.The crude product was purified by column chromatography to give 4-(4-bromo-2-fluorophenyl)morpholine.

According to the analysis of related databases, 912773-21-8, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Ocean University of China; Shao Changlun; (69 pag.)CN108658937; (2018); 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. 768-05-8, name is Pyrazinoic acid hydrazide, A new synthetic method of this compound is introduced below., Computed Properties of C5H6N4O

General procedure: The 2-(3-methylbutanoyl)-1H-indene-1,3(2H)-dione neededfor the synthesis was prepared by the Claisen condensation of diethylphthlate and appropriate ketone under the inuence ofsodium methoxide according to the procedure as described inthe literature.32,33 Schi bases were synthesized by dissolving 1:1molar ratio methanolic solution of 2-(3-methylbutanoyl)-1Hindene-1,3(2H)-dione with benzoic acid, pyrazine acid, nicotinic acid, and isonicotinic acid hydrazides. The solution wasstirred and reuxed for 5-6 h. The solution was kept overnightat room temperature. The white and red color solids so obtainedwere fltered and recrystallized in methanol and chloroformsolution (1:1, v/v).

The synthetic route of 768-05-8 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Khatkar, Priyanka; Asija, Sonika; Phosphorus, Sulfur and Silicon and the Related Elements; vol. 192; 4; (2017); p. 446 – 453;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 69214-33-1,Some common heterocyclic compound, 69214-33-1, name is 8-Chloroimidazo[1,2-a]pyrazine, molecular formula is C6H4ClN3, 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.

A slurry of Intermediate B (400 mg, 1.6 mmol), 8-chloroimidazo[l,2-a]pyrazine (272 mg, 1.77 mmol) and Hunig’s Base (0.84 ml, 4.8 mmol) in DMA (10 ml) was heated at 75 C overnight. The cooled reaction mixture was partitioned between ethyl acetate and sat. aqueous sodium bicarbonate solution. The organic layer was washed with brine (2 x 50 mL) followed by water (2 x 50 mL). The organic layer was separated, dried over sodium sulfate, filtered and concentrated to dryness. The crude oil was dissolved in minimal DCM and purified by silica gel column chromatography (0-100% ethyl acetate in hexanes, 20 min) to afford 21-1 as an oil. LRMS m/z (M+H) 366.3 found, 366.4 required.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 8-Chloroimidazo[1,2-a]pyrazine, its application will become more common.

Reference:
Patent; MERCK SHARP & DOHME CORP.; KUDUK, Scott, D.; REGER, Thomas, S.; SKUDLAREK, Jason, W.; (0 pag.)WO2016/85784; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem