Pyrazines

Application of 23611-75-8, 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. 23611-75-8, name is Methyl 6-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Example 15; 6-((3aR,6aS)-hexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl)-N-m-tolylpyrazine-2-carboxamide; Example 15A; 6-chloropyrazine-2-carboxylic Acid; The product from Example 1E (1.78 g, 10.3 mmol) was dissolved in EtOH (25 mL). 1M NaOH (25 mL) was added, and the reaction stirred at ambient temperature for 2 h. The reaction mixture was acidified to pH?3 with 1M HCl (aq). The mixture was then diluted with water (150 mL) and extracted with EtOAc (4×100 mL). The organic extracts were combined, washed with brine (100 mL), dried over Na2SO4, filtered and concentrated under vacuum to provide the title compound as a white solid (1.54 g, 94%). MS (DCI/NH3) m/z 176 (M+NH4)+.

The synthetic route of Methyl 6-chloropyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Abbott Laboratories; US2009/281118; (2009); 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. 32974-92-8, name is 1-(3-Ethylpyrazin-2-yl)ethanone, A new synthetic method of this compound is introduced below., name: 1-(3-Ethylpyrazin-2-yl)ethanone

(1) 2-acetyl-3-ethylpyrazine (420 ul, 3 mmol) was dissolved in methanol (20 ml).After dissolution,Add 4,4-dimethyl-3-thiosemicarbazide (360 mg, 3 mmol),well mixed,The mixed solution was refluxed at 65 C for 4 h.filter,The filtrate is volatilized at room temperature.There are pale yellow crystals,Filter again,Wash 2-3 times with absolute ethanol,Obtaining a ligand L4;

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; Guangxi Normal University; Yang Feng; Sun Zewen; Zhao Lei; Liang Hong; (16 pag.)CN109796501; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 36070-75-4, name is 5-Chloropyrazine-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 36070-75-4, COA of Formula: C5H2ClN3

1-((2S,4/?)-4-amino-6-bromo-2-methyl-3,4-dihydroquinolin-1 (2/-/)-yl)ethanone (for a preparation, see Intermediate 1 ) (50 mg, 0.177 mmol), 5-chloropyrazine-2-carbonitrile (37.0 mg, 0.265 mmol) and DIPEA (0.123 mL, 0.706 mmol) were combined in NMP (1 .5 mL) and heated in a sealed flask under microwave irradiation to 200C for 1 h. The mixture was partitioned between water (150 mL) and EtOAc (4×100 mL). The organic layers were combined, washed with brine (2×100 mL), dried by passing through a hydrophobic frit, and concentrated in vacuo. The resulting residue was purified by chromatography (25 g column, EtOAc/cyclohexane gradient) to give 5-(((2S,4/?)-1-acetyl- 6-bromo-2-methyl-1 ,2,3,4-tetrahydroquinolin-4-yl)amino)pyrazine-2-carbonitrile (61 mg, 0.158 mmol, 89 % yield) as a brown gum.LCMS (Formate, 2 min), Rt = 0.94 mins, MH+ = 386/388.

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-Chloropyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXOSMITHKLINE LLC; AMANS, Dominique; DEMONT, Emmanuel Hubert; MITCHELL, Darren Jason; SEAL, Jonathan Thomas; WO2012/143415; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 63744-22-9, 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. 63744-22-9 name is 6,8-Dibromoimidazo[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.

A mixture of 3,4-dimethoxyaniline (18.0 g, 118 mmol), 6,8- dibromoimidazo[1 ,2-a]pyrazine (25.0 g, 90.4 mmol), and Lambda/,Lambda/-diisopropylethylamine (11.7 g, 90.4 mmol) in DMF (500 ml_) was stirred at 120 0C overnight. After this time, the reaction was cooled to room temperature and concentrated to approximately 100 ml_ under reduced pressure. The dark brown reaction mixture was poured into ice-cold water (300 ml_) and stirred for 10 min. The resulting brown precipitate was filtered and the filter cake washed with water (100 ml_). The filter cake was dried under vacuum and recrystallization from methanol (-800 ml_) to afford 6-bromo-Lambda/-(3,4,5- trimethoxyphenyl)imidazo[1 ,2-a]pyrazin-8-amine (2) (23.3 g, 74%) as a light brown needle-shaped solid: 1H NMR (300 MHz, DMSO-Gf6) 9.81 (s, 1 H), 8.22 (s, 1 H), 7.93 (s, 1 H), 7.75 (d, J = 2.4 Hz, 1 H), 7.62 (s, 1 H), 7.53 (dd, J= 8.7, 2.4, 1 H), 6.94 (d, J= 8.7 Hz, 1 H), 3.77 (s, 3H), 3.75 (s, 3H); ESI MS m/z 349.2 [M + H]+; HPLC, 6.92 min, >99% (AUC).

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

Reference:
Patent; CGI PHARMACEUTICALS, INC.; MITCHELL, Scott A.; CURRIE, Kevin S.; BLOMGREN, Peter A.; KROPF, Jeffrey E.; LEE, Seung H.; XU, Jianjun; STAFFORD, Douglas G.; HARDING, James P.; BARBOSA, Jr., Antonio J.; ZHAO, Zhongdong; WO2010/68257; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 14508-49-7, name is 2-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 14508-49-7, category: Pyrazines

The product of preparation 16 (83mg, 0.32mmol), 2-chloropyrazine (36mg, 0.31 mmol), sodium tert-butoxide, (36mg, 0.37mmol), Pd2(dba)3 (7mg, 8mumol) and BINAP (22mg, 35mumol) were suspended in tert-butanol (2mL) and the mixture was heated at 110C in the microwave for 3 hours. The mixture was replenished with further amounts of 2-chloropyrazine (36mg, 0.31 mmol), sodium tert-butoxide (36mg, 0.37mmol), Pd2(dba)3 (7mg, 8mumol) and BINAP (22mg, 30mumol) at hourly intervals. The reaction mixture was then azeotroped with methanol and concentrated in vacuo. The residue was purified by column chromatography on silica gel, eluting with ethyl acetate:methanol: 0.88 ammonia, 100:0:0 to 90:10:1. This was followed by further purification by column chromatography on Biotage amino silica gel, eluting with pentane:ethyl acetate, 100:0 to 0:100, to afford the title compound as a colourless oil in 76% yield, 80mg. 1HNMR(CDCl3, 400MHz) delta: 1.70-1.90(m, 4H), 1.91-2.04(m, 2H), 2.47-2.63(m, 6H), 2.93-3.02(m, 2H), 3.90-3.98(m, 2H) 4.28-4.35(m, 2H), 4.63(s, 2H), 6.60(d, 1H), 7.37(d, 1H), 7.85(m, 1H), 8.10(m, 1H), 8.21(m,1H) MS APCI+ m/z 340 [MH]+ Micro analysis found (%); C(67.21), H(7.46), N(20.60); C19H25N5NO requires (%); C(67.31), H(7.42), N(20.63)

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

Reference:
Patent; Pfizer Limited; EP1595881; (2005); 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C4H3Br2N3

A solution of intermediate 1-01(15 g, 59.3 mmol) inmorpholine (15 ml, 178 mmol) was heated at 120 C. in a Parr reactor for 48 h. A brown solid appears. The solid was suspended in DCM and washed with NaHCO3 aq. sat (twice). The organic phase was dried (NaSO4), filtered and evaporated to dryness to obtain 1-02, 14.8 g of a brown solid(Y: 96%)

The synthetic route of 24241-18-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; CENTRO NACIONAL DE INVESTIGACIONES ONCOLOGICAS (CNIO); Serrano Marugan, Manuel; Pastor Fernandez, Joaquin; Martinez Gonzalez, Sonia; Ortega Molina, Ana; Bischoff, James R.; Oyarzabal Santamarina, Julen; (220 pag.)US9993554; (2018); B2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 6164-79-0, The chemical industry reduces the impact on the environment during synthesis 6164-79-0, name is Methyl 2-pyrazinecarboxylate, I believe this compound will play a more active role in future production and life.

(1) Pyrazine-2-carboxylic acid is fully dissolved in anhydrous methanol,Then add an appropriate amount of concentrated sulfuric acid and heat to reflux for 5 h.After the reaction is cooled, adjust the pH to neutral with saturated NaHCO3,Extract with dichloromethane and keep the dichloromethane layer,The solvent was removed by rotary evaporation to obtain an oily pyrazine-2-carboxylic acid methyl ester;After dissolving it in anhydrous methanol, hydrazine hydrate was added dropwise, and after heating under reflux for 21 h,Cool to room temperature, remove methanol by rotary evaporation to obtain pyrazine-2-hydrazide as a red solid product;The ratio of the amount of pyrazine-2-carboxylic acid methyl ester to the amount of hydrazine hydrate is 1: 2.

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, Methyl 2-pyrazinecarboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Tianjin Medical University; Xu Jingyuan; Wang Zhigang; Xie Chengzhi; (13 pag.)CN110372681; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 16298-03-6,Some common heterocyclic compound, 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, molecular formula is C6H7N3O2, 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.

Methyl 2-amino-3-pyrazine carboxylate (2. 2 g) was dissolved in dry DCM (20 ml) to give a cloudy pale yellow solution, and pyridine (2 ml) in dry DCM (12 ml) was added. The stirred suspension was cooled in an ice bath, and 2,4, 6-trifluorophenylacetyl chloride (3.0 g) in dry DCM (13 ml) was added dropwise. The reaction gradually became a deep orange, and then went clear. It was stirred for 6 hours and stood overnight. The reaction mixture was washed with water, brine, and then dilute hydrochloric acid, and the DCM layer was dried over magnesium sulphate. The solvent was evaporated to yield an orange solid which was triturated with ether, to give methyl 2- [2, 4, 6-TRIFLUOROPHENYLACETYLAMINO]-3-PYRAZINE carboxylate as a yellow solid (1.5 g). LH NM : R (CDC13) 8 ppm: 4.03 (s, 5H), 6.74 (t, 2H), 8.43 (d, LH), 8.61 (d, LH) 10.9 (s, LH).

The synthetic route of 16298-03-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SYNGENTA LIMITED; SYNGENTA PARTICIPATIONS AG; WO2004/56825; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 19847-12-2, 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. 19847-12-2, name is Pyrazinecarbonitrile belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

General procedure: To an oven dried rb flask with a magnetic stir bar were added 2-amiobenzamide 1a (136.0 mg, 1.0 mmol), nitrile derivative 2 (108.0 mg, 1.0 mmol), anhydrous zinc iodide (0.3 equiv, 96 mg) and the mixture were stirred in 5 mL acetonitrile for 1h at room temperature. Then iodine (51 mg, 0.2 mmol) and aq. TBHP (70% solution in water, 0.26 mL, 2.0 mmol) were added successively and the mixture stirred at rt for another 2 h. After completion of the reaction (TLC monitoring), the reaction mixture was quenched by aq. Na2S2O3 solution (5%, 20 mL), extracted with ethyl acetate (10 mL × 3), and the combined organic part was dried over anhydrous sodium sulphate. Removal of the solvent under reduced pressure left a crude mass which was purified by column chromatography using silica gel (25% EtOAc/hexane) to afford 3a (155 mg; 80% yield).

The synthetic route of Pyrazinecarbonitrile has been constantly updated, and we look forward to future research findings.

Reference:
Article; Saha, Moumita; Das, Asish R.; Tetrahedron Letters; vol. 59; 26; (2018); p. 2520 – 2525;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, 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. HPLC of Formula: C6H2N2O3

General procedure: 4-Aminophenyl selenocyanate (2mmol) was dissolved in dry acetone (15mL) and the corresponding anhydride (2mmol) then added. The reaction was then stirred for a variable time of 12h up to 48h at room temperature. Reaction was quenched with water, compound was then filtered and purified by stirring or washing with solvents such as n-hexane and ethyl ether. The chemical shifts assignment in NMR spectroscopy for these compounds is exemplified in Fig.12.

The synthetic route of 2,3-Pyrazinecarboxylic anhydride has been constantly updated, and we look forward to future research findings.

Reference:
Article; Garnica, Pablo; Encio, Ignacio; Plano, Daniel; Palop, Juan A.; Sanmartin, Carmen; European Journal of Medicinal Chemistry; vol. 175; (2019); p. 234 – 246;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem