Pyrazines

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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 33332-25-1

Intermediate 33: 5-Chloropyrazine-2-carboxylic acid To a solution of methyl-5-chloropyrazine-2-carboxylate (120 mg, 0.70 mmol) in a mixture of acetonitrile (2 mL) and DMF (1 mL) was added lithium chloride (295 mg, 6.95 mmol). The suspension was heated to 160 C. for 5 minutes in a microwave after which time the reaction was diluted with water (10 mL). Saturated sodium bicarbonate solution (20 mL) was added and the aqueous layered extracted with ethyl acetate (2*30 mL). The organic extracts were discarded and the aqueous layer adjusted to pH 4 with 1N hydrochloric acid. The aqueous phase was extracted twice with ethyl acetate (20 mL) and the combined organics washed with water (2*20 mL) and brine (10 mL) and dried (MgSO4). The volatiles were removed under reduced pressure to afford the product (68 mg). 1H NMR delta (400 MHZ, CDCl3): 7.20 (1H, br s), 8.72 (1H, s), 9.21-9.21 (1H, m); m/z 157 (M-H)+.

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AstraZeneca AB; US2008/171734; (2008); A1;,
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Application of 77112-53-9, The chemical industry reduces the impact on the environment during synthesis 77112-53-9, name is Imidazo[1,2-a]pyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

General procedure: Imidazo[1,2-a]pyrazine-2-carboxylic acid (5) (1.0 equiv.) Mukaiyama?s reagent and 2-chloro-1-methylpyridinium iodide (1.2 equiv.) were suspended in DMF (5.0 mL) under nitrogen atmosphere. Into the reaction mixture, aliphatic/aromatic amines (6a-l) (1.0 equiv.) and 1-methylimidazole (2.0 equiv.) were added. A homogeneous solution was formed after a gentle stirring. The reaction mixture was sealed in a microwave glass reactor and then irradiated by microwave oven at a constant temperature of 80 C with continuous stirring (1 min ramp, 15 min reaction time). After the reaction was completed, the solvent was removed through a rotary evaporator and the resulting residue was extracted by a biphasic system of 45 mL diethyl ether and 45 mL water. After the layer separation, the ether layer was dried by anhydrous sodium sulphate, followed by an evaporation of ether to get compounds 7a-l (Scheme-I).

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, Imidazo[1,2-a]pyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Jyothi, Boggavarapu; Madhavi, Nannapaneni; Asian Journal of Chemistry; vol. 32; 1; (2020); p. 84 – 90;,
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Some common heterocyclic compound, 41110-29-6, name is Methyl 3-methylpyrazine-2-carboxylate, molecular formula is C7H8N2O2, 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. COA of Formula: C7H8N2O2

In a 1-L flask, the methyl 3-methylpyrazine-2-carboxylate (step 1, 16.08 g, 106 mmol) was suspended in CHCl3 (300 mL). 3-chlorobenzoperoxoic acid (Aldrich, 24.62 g, 143 mmol) was added. The reaction mixture was heated to 70 C. for 16 h. The reaction mixture was quenched with saturated NaHCO3 (200 mL). The layers were separated, and the aqueous layer was further extracted with DCM (2×100 mL). The combined organic layers were dried over MgSO4, and the filtrate was concentrated to afford the title compound. MS m/z=169 (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 41110-29-6, its application will become more common.

Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); A1;,
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Synthetic Route of 13134-38-8, 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. 13134-38-8, name is 3,6-Dimethylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

e) Ethyl-N-[(3,6-dimethylpyrazin-2-yl)carbamothioyl]carbamate To a solution of 3, 6-dimethyl-pyrazin-2-ylamine (5 g, 40.65 mmol) in dioxane (150ml) was added ethoxycarbonyl isothiocyanate (4.75 ml, 40.65 mmol) at 25 C, and the reaction mixture was stirred for 18 hours at 25 C. Volatiles were removed in vacuo. The resultant residue was dissolved in ethyl acetate, washed with water twice, and brine, dried over anhydrous sodium sulfate, filtered, and evaporated affording ethyl-N-[(3,6-dimethylpyrazin-2- yl)carbamothioyl] carbamate (10 g, 96.73%) as a light yellow solid. MS: m/z= 255 (M+H+)

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, 3,6-Dimethylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; HOFFMANN-LA ROCHE INC.; FLOHR, Alexander; GROEBKE ZBINDEN, Katrin; KUHN, Bernd; LERNER, Christian; RUDOLPH, Markus; SCHAFFHAUSER, Herve; WO2013/178572; (2013); A1;,
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Reference of 1379338-74-5,Some common heterocyclic compound, 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine, molecular formula is C7H3Cl2N3, 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.

Intermediate 5: 1 ,1-Dimethylethyl (3 ~)-3-fr(7-chloropyridor3,4-blpyrazin-5- yl)amino1methviyi-piperidinecarboxylate; 5,7-dichloropyrido[3,4-b]pyrazine (1g, 5.00mmol) was taken up in N-Methyl-2- pyrrolidone (NMP) (10ml) and treated with 1 , 1-dimethylethyl (3f~)-3-(aminomethyl)-1- piperidinecarboxylate (1.179g, 5.50mmol) (Apollo Scientific Ltd) and diisopropylethylamine (1.310ml, 7.50mmol). The reaction was irradiated in a Biotage microwave at 130C for 30min. The reaction was partitioned between EtOAc (100ml) and water (100ml). The organic layer was washed with brine (100ml), dried using a hydrophobic frit and concentrated to give a black solid. This solid was purified on silica (50g) and eluted with a 10-40% EtOAc/cyclohexane gradient. The appropriate fractions were combined and concentrated to give the title compound as a deep orange solid (1.542g).LCMS (Method B): Rt = 1.28min, MH+ = 377.92

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5,7-Dichloropyrido[3,4-b]pyrazine, its application will become more common.

Reference:
Patent; GLAXO GROUP LIMITED; ATKINSON, Francis Louis; ATKINSON, Stephen John; BARKER, Michael David; DOUAULT, Clement; GARTON, Neil Stuart; LIDDLE, John; PATEL, Vipulkumar Kantibhai; PRESTON, Alexander G; SHIPLEY, Tracy Jane; WILSON, David Matthew; WATSON, Robert J; WO2012/123312; (2012); A1;,
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Synthetic Route of 22047-25-2,Some common heterocyclic compound, 22047-25-2, name is Acetylpyrazine, molecular formula is C6H6N2O, 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.

Preparation 4; 1-Pyrazin-2-yl-ethylamine; The synthetic procedure used in this preparation is outlined below in Scheme F. To a solution of 1-pyrazin-2-yl-ethanone (2.0 g, 15.85 mmol) and ammonium acetate (19.337 g, 158.5 mmol) in methanol (50 mL) was added sodium cyanoborohydride (0.7 g, 11.1 mmol) in one portion. The reaction mixture was stirred overnight at room temperature. After removal of methanol, water (20 mL) was added to the residue and the resulting solution was basified by addition of sodium hydroxide to pH=13. The aqueous solution was extracted with dicholromethane and the combined organic phase was dried over sodium sulfate. Removal of the solvent under reduced pressure afforded 14.62 g of 1-pyrazin-2-yl-ethylamine, yield: 75%. MS (M+H)=124.

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

Reference:
Patent; Roche Palo Alto LLC; US2009/163499; (2009); A1;,
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Pyrazine | C4H4N2 – PubChem

Application of 21279-62-9,Some common heterocyclic compound, 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, molecular formula is C5H4ClN3O, 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.

General procedure: Compounds 1-6 were prepared according to conventional organic synthesis methods. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was dissolved in THF (20 mL) in a round bottom flask and after that treated with two equivalents of the corresponding benzylamine and an equimolar amount of triethylamine. The reaction was conducted with continuous stirring and heating (70 C) under reflux in an oil bath for 15 h. Compounds 7-15 were synthesised using a microwave reactor with a focused field. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was put into a thick-walled tube together with the corresponding benzylamine (2.54 mmol), pyridine (1.27 mmol), methanol (approx. 5 mL) and a magnetic stir bar and then sealed with a special cap. The reaction parameters were set according to the previously published paper as follows-140 C, 30 min, 200 W [29]. Reaction progress was checked by TLC (hexane:ethyl acetate-1:1). Regardless of the synthesis method used,all reaction mixtures were adsorbed on silica and subjected to preparative flash chromatography (hexane and ethyl acetate, gradient elution, detection wavelengths 260 nm and 280 nm). Products were recrystallized from ethanol or ethanol and water if necessary. All final substances were chemically characterized (1H-NMR, 13C-NMR, IR, melting point and elemental analysis).

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

Reference:
Article; Jandourek, Ondrej; Tauchman, Marek; Paterova, Pavla; Konecna, Klara; Navratilova, Lucie; Kubicek, Vladimir; Holas, Ondrej; Zitko, Jan; Dolezal, Martin; Molecules; vol. 22; 2; (2017);,
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Electric Literature of 63286-28-2,Some common heterocyclic compound, 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, molecular formula is C4H5ClN4, 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.

-Chloro-3-hydrazinylpyrazine (440 g, 3.0 mol) was suspended in acetic acid (500 mL) and cooled to lOoC. A solution of sodium nitrite (220 g, 3.2 mol) in water (200 mL) at 10 C was added. The resulting mixture was stirred at 10 C for 1 h, during which time a crystalline solid precipitated. The precipitate was collected by filtration, washed with ethanol (200 mL) and dried to afford the desired product as a red solid (350 g, 73% yield).

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

Reference:
Patent; KALYPSYS, INC.; CHEN, Pingyun; CARINO, Stephen, A., R.; COUCH, Ricky, W.; KINDER, Daniel, S.; NORTON, Beth, A.; WO2013/39785; (2013); A2;,
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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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., SDS of cas: 16298-03-6

Hydrazine hydrate (34 mL, 1.1 mol) was added portionwise to a stirred suspension of methyl 3-aminopyrazine-2-carboxylate 37 (21.3 g, 139 mmol) in ethanol (65 mL) at room temperature. The resulting slurry was stirred at 60 °C for 2 h, cooled to room temperature, and filtered. The solid was washed with cold ethanol (2 x 25 mL) and dried to a constant weight to afford 3-aminopyrazine-2-carbohydrazide (20.75 g, 97percent) as a beige solid. TBTU (5.77 g, 18.0 mmol) was added portionwise over 15 min to a stirred suspension of DIPEA (8.5 mL, 49 mmol), 1-methylcyclopropanecarboxylic acid (1.63 g, 16.3 mmol) and 3-aminopyrazine-2-carbohydrazide (2.50 g, 16.3 mmol) in acetonitrile (40 mL). The mixture was stirred at 80 °C for 20 min, and then cooled to 0 °C. DIPEA (8.5 mL, 49 mmol) followed by 4-methylbenzene-1-sulfonylchloride (9.34 g, 49 mmol) were added over a period of 15 min. The reaction mixture was brought to reflux and allowed to stir at room temperature for 14 h. The mixture was concentrated, and the residue was diluted with DCM, washed with water and brine, dried over magnesium sulfate and concentrated. The crude product was purified by flash chromatography on silica gel eluting with 0 to 40percent ethyl acetate in dichloromethane. After evaporation of the solvent, the resulting solid was triturated with diethyl ether, filtered, washed with the minimum of diethyl ether and dried to afford 3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (2.12 g, 60percent). NBS (1.87 g, 10.5 mmol) was added portionwise to a solution of 3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (2.08 g, 9.6 mmol) in THF (30 mL). The reaction mixture was stirred at room temperature for 16 h and concentrated. The residue was dissolved in dichloromethane (150 mL), washed with water (2 x 40 mL), brine, dried over magnesium sulfate and concentrated. After evaporation of the solvents, the crude product was purified by flash chromatography on silica gel eluting with 0 to 10percent ethyl acetate in dichloromethane. The solvent was evaporated to dryness to afford 5-bromo-3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (2.50 g, 88percent) as a yellow solid. Bis(triphenylphosphine)palladium(II) chloride (59 mg, 0.08 mmol) was added in one portion to a stirred solution of 5-bromo-3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (500 mg, 1.69 mmol) and hexamethyldistannane (0.49 mL, 2.4 mmol) dissolved in dioxane (8 mL) under argon. The resulting suspension was stirred at 80 °C for 1 h. The mixture was evaporated. The crude product was purified by flash chromatography on silica gel eluting with 10 to 30percent ethyl acetate in dichloromethane. The solvent was evaporated to dryness to afford 3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)-5-(trimethylstannyl)pyrazin-2-amine 38a (314 mg, 49percent) as a yellow crystalline solid.

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 16298-03-6.

Reference:
Article; Barlaam, Bernard; Cosulich, Sabina; Delouvrie, Benedicte; Ellston, Rebecca; Fitzek, Martina; Germain, Herve; Green, Stephen; Hancox, Urs; Harris, Craig S.; Hudson, Kevin; Lambert-Van Der Brempt, Christine; Lebraud, Honorine; Magnien, Francoise; Lamorlette, Maryannick; Le Griffon, Antoine; Morgentin, Remy; Ouvry, Gilles; Page, Ken; Pasquet, Georges; Polanska, Urszula; Ruston, Linette; Saleh, Twana; Vautier, Michel; Ward, Lara; Bioorganic and Medicinal Chemistry Letters; vol. 25; 22; (2015); p. 5155 – 5162;,
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Application of 1379338-74-5,Some common heterocyclic compound, 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine, molecular formula is C7H3Cl2N3, 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.

Intermediate 33: 1,1-Dimethylethyl-2-{[(7-chloropyrido[3,4-b]pyrazin-5-yl)amino]methyl}-4-morpholinecarboxylate 1,1-Dimethylethyl-2-(aminomethyl)-4-morpholinecarboxylate (60 mg, 0.28 mmol) was dissolved in N-methyl-2-pyrrolidinone (NMP) (1 mL) and to this was added DIPEA (0.07 mL, 0.38 mmol) and 5,7-dichloropyrido[3,4-b]pyrazine (50 mg, 0.25 mmol). This was heated at 130 C. for 30 min. The reaction mixtures were partitioned between ethyl acetate (50 ml) and water (50 mL) and the organic layer washed with water (50 mL), dried over a hydrophobic frit and concentrated in vacuo to yield an orange gum. It was dissolved in DCM and passed through silica (10 g) eluting with a 10-40% ethyl acetate in cyclohexane gradient. Appropriate fractions were combined and concentrated in vacuo to yield the title compound as a yellow solid, 91 mg. LCMS (Method B): Rt=1.17 min, MH+ 380

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5,7-Dichloropyrido[3,4-b]pyrazine, its application will become more common.

Reference:
Patent; GLAXO GROUP LIMITED; Atkinson, Francis Louis; Atkinson, Stephen John; Barker, Michael David; Douault, Clement; Garton, Neil Stuart; Liddle, John; Patel, Vipulkumar Kantibhai; Preston, Alexander G.; Shipley, Tracy Jane; Wilson, David Matthew; Watson, Robert J.; US2014/5188; (2014); A1;,
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Pyrazine | C4H4N2 – PubChem