Tag: M.W=100-200

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. 13924-95-3, name is Methyl 5-hydroxypyrazine-2-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C6H6N2O3

1) Synthesis of methyl 5-fluoromethoxypyrazine-2-carboxylateFluoromethyl toluene-4-sulfonate (Journal of Labelled Compounds and Radiopharmaceuticals, 46 (6), 555-566; 2003) (344 mg) and cesium carbonate (824 mg) were added to a solution of methyl 5-hydroxypyrazine-2-carboxylate (130 mg) in DMF (2.0 mL). The reaction solution was stirred at 70C for 5 h and 30 min and then cooled to RT. Water was added to the reaction solution, followed by extraction with EtOAc. The organic layer was concentrated under reduced pressure. The residue was purified by NH-silica gel column chromatography to obtain the title compound (18.0 mg). 1H-NMR (400 MHz, CDCl3) delta (ppm): 4.03 (s, 3H), 6.14 (d, J = 51.2 Hz, 2H), 8.42 (d, J = 1.2 Hz, IH), 8.94 (d, J = 1.2 Hz, IH).

According to the analysis of related databases, 13924-95-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; EISAI R&D MANAGEMENT CO., LTD; ELLARD, John Mark; FARTHING, Christopher Neil; HALL, Adrian; WO2011/9898; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 122-05-4, The chemical industry reduces the impact on the environment during synthesis 122-05-4, name is Pyrazine-2,5-dicarboxylic acid, I believe this compound will play a more active role in future production and life.

Example 42: Synthesis of (tetrakis(2′,6′-difluoro-2, 3′-bipyridinato)(mu-2,5-pyrazinedicarboxylate) diiridium(III), Abbreviation; [Ir(dfpypy)225PDC]2) [0408] [0409] Under argon atmosphere, into a 30 mL Schlenk flask equipped with a stirrer were placed 31 mg (0.15 mmol) of 2,5-pyrazinedicarboxylic acid, 16 mg (0.30 mmol) of sodium methoxide and 20 ml of methanol. And then, the mixture was reacted under stirring at room temperature for 2 hours. After the solvent was distilled off under reduced pressure, 184 mg (0.15 mmol) of di-mu-chloro-tetrakis(2′,6′-difluoro-2, 3′-bipyridinato) diiridium(III) and 25 ml of 2-ethoxyethanol were added to the residue, and then the resultant mixture was reacted under stirring at 110 C for 20 hours. After the completion of the reaction, the solvent was distilled off under reduced pressure. Subsequently, 30 ml of dichloromethane was added to the concentrate, and then the resultant mixture was filtered. The precipitate collected by filtration was washed with pure water, and then dried under reduced pressure, to provide 166 mg of tetrakis(2′,6′-difluoro-2, 3′-bipyridinato)(mu-2,5-pyrazinedicarboxylate) diiridium(III) as an orange solid. (84%) [0410] Additionally, tetrakis(2′,6′-difluoro-2, 3′-bipyridinato)(mu-2,5-pyrazinedicarboxylate) diiridium(III) had the following properties: [0411] 1H-NMR (400MHz, d-DMF, delta (ppm)); 8.64 (d, 2H), 8.51 (s, 2H), 8.46-8.24 (m, 6H), 8.17 (dt, 2H), 7.92 (dd, 2H), 7.73 (ddd, 2H), 7.15 (ddd, 2H), 6.01 (s, 2H), 5.50 (s, 2H) FD-MS (M/Z): 1316 M+

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, Pyrazine-2,5-dicarboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Ube Industries, Ltd.; FUJIMURA, Osamu; FUKUNAGA, Kenji; IWASA, Takafumi; TANAKA, Yasuhiro; FUJITA, Harunori; MURAKAMI, Tadashi; HONMA, Takashi; MACHIDA, Toshikazu; KASHIHARA, Natsuko; EP2647642; (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. 14508-49-7, name is 2-Chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Safety of 2-Chloropyrazine

General procedure: A 10 mL round-bottom flask was charged with the prescribedamount of catalyst Pd/Cu, aryl chlorides (0.5 mmol), phenylboronicacids containing hydroxymethyl (0.75 mmol), Cs2CO3 (1.0 mmol)and dioxane (5 mL) in air. The reaction mixture was then placedin an oil bath and heated at 110 C for 24 h. After removal of thesolvent, the resulting residue was purified by flash chromatographyon silica gel using CH2Cl2 as eluent. The products 4a-k, and4m are known compounds [6,9] except for 4l and 4n.

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 14508-49-7.

Reference:
Article; Xu, Chen; Li, Hong-Mei; Wang, Zhi-Qiang; Fu, Wei-Jun; Inorganica Chimica Acta; vol. 423; PART A; (2014); p. 11 – 15;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 873-40-5, The chemical industry reduces the impact on the environment during synthesis 873-40-5, name is 2,3,5-Trichloropyrazine, I believe this compound will play a more active role in future production and life.

2, 3, 5-trichloropyrazine (70.50 g, 384.36 mmol, 1 equiv) and ammonia solution (25% wt, 364.00 g, 400 mL, 2.68 mol, 6.14 equiv) were added to a l-L sealed reactor. The mixture was heated to 80 C and stirred for 24 h, and the reaction was completed. The reaction mixture was cooled to 30 C and filtered to give a brown filter cake. The brown filter cake was dissolved in acetone (50 mL), and filtered. To the filtrate was added petroleum ether (300 mL). The suspension was stirred for 4 h, and filtered to give the crude product. The crude product was slurried in combined solvents of petroleum ether and acetone (10/1, 200 mL) and filtered to give the product Y7d (51.00 g, 307.91 mmol, 80% yield) as a light yellow solid. 1H NMR (400 MHz, DMSO-d6) d = 7.63 (s, 1H). The advantage of this (also generalized) method is that no column chromatography is required to obtain Y7d.

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, 2,3,5-Trichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; NOVARTIS AG; FEI, Zhongbo; ZHANG, Hao; JIA, Huanqing; WANG, Hui; WANG, Jianhua; LI, Wei; LIN, Xiaohui; MIN, Zhongcheng; (91 pag.)WO2020/65452; (2020); 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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, A new synthetic method of this compound is introduced below., Safety of Methyl 2-aminopyrazine-3-carboxylate

In 20 ml of concentrated hydrochloric acid, 3.06 g (20 mmol, 1 eq.) of 3-amino-2-pyrazine methyl carboxylate is introduced at 0 C. A solution of 1.52 g (22 mmol, 1.1 eq.) of NaNO2 in 15 ml of water is then introduced drop by drop, while limiting the temperature to <5 C., until the gaseous emission stops. The solution obtained is filtered and added slowly to a sodium acetate solution (20 g) in 40 ml of water at 0 C. Stirring is maintained for 15 min, and then acidified with concentrated HCl. Extraction (4 times 30 ml of ethyl acetate) gives 1.35 g of chlorinated compound after drying and evaporation. NMR (1H, CDCl3): 4.05 (s; 3H; OCH3), 8.54 (d, J=2.4 Hz; 1H; arom. H), 8.60 (d, J=2.4 Hz; 1H; arom. H). 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; Imbert, Thierry; Monse, Barbara; Koek, Wouter; US2005/80085; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 21279-62-9, These common heterocyclic compound, 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, 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.

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).

Statistics shows that 3-Chloropyrazine-2-carboxamide is playing an increasingly important role. we look forward to future research findings about 21279-62-9.

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);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 113305-94-5,Some common heterocyclic compound, 113305-94-5, name is 5-Aminopyrazine-2-carbonitrile, molecular formula is C5H4N4, 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.

5-Aminopyrazine-2-carbonitrile (5.45 mg, 0.045 mmol), Xantphos (1.749 mg, 3.02 mumol), tris(dibenzyiideneacetone)dipalladium(0) (1.384 mg, 1.511 mumol), and cesium carbonate (24.62 mg, 0.076 mmol) were added to tert-butyl 4-((2-chloro-5-(4-methoxyphenyl)pyridin- 4-ylamino)methyl)-4-fluoropiperidine-1-carboxylate (17 mg, 0.038 mmol) in a 0.2 mL microwave reaction vial. The vial was sealed and an inert atmosphere was introduced before dry dioxane (291 muL) was added. Nitrogen was bubbled through the mixture for 5 min. The mixture was heated at 150 0C for 1 hr by microwave irradiation. After cooling the mixture was diluted with 20% dichloromethane in MeOH and loaed onto a preparative thin layer chromatography plate. Elution with 50% EtOAc in hexane gave tert-butyl 4-((2-(5- cyanopyrazin-2-ylamino)-5-(4-methoxyphenyl)pyridin-4-ylamino)methyl)-4- fluoropiperidine-1-carboxylate (1.5 mg, 2.81 mumol, 7% yield) as a light yellow powder. LCMS (4) Rt = 2.35 min; m/z (ESI+) 534 (MH+). Trifluoroacetic acid (0.1 mL, 1.298 mmol) was added to tert-butyl 4-((2-(5-cyanopyrazin-2-ylamino)-5-(4-methoxyphenyl)pyridin-4- ylamino)methyl)-4-fluoropiperidine-1-carboxylate (1.5 mg, 2.81 mumol) dissolved in dichloromethane (0.5 mL) and the solution was stirred for 1 hr. The volatiles were removed in vacuo and the crude product was purified by ion exchange on lsolute SCX Il acidic resin (1 g), followed by preparative thin layer chromatography, eluting with 10% MeOH / 1% NH3 / 89% dichloromethane, to give 5-(4-((4-fluoropiperidin-4- yl)methylamino)-5-(4-methoxyphenyl)pyridin-2-ylamino)pyrazine-2-carbonitrile (1 mg, 2.307 mumol, 82% yield) as a yellow powder.1H NMR (500 MHz, MeOD) delta 8.87 (s, 1 H), 8.59 (s, 1 H), 7.75 (s, 1 H), 7.33 (d, 2H, J = 8.5 Hz), 7.21 (s, 1 H), 7.07 (d, 2H, J = 8.5 Hz), 3.86 (s, 3H), 3.44 (d, 2H, J = 19.5 Hz), 3.08- 2.93 (m, 4H), 1.96-1.69 (m, 4H). LCMS (4) Rt = 1.62 min; m/z (ESI+) 434 (MH+).

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

Reference:
Patent; CANCER RESEARCH TECHNOLOGY LIMITED; WO2009/44162; (2009); A1;,
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. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Quality Control of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine

A solution of (2R)-(-)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine (4.25 g, 23.1 mmol) in tetrahydrofuran (30 ml) was cooled to -78° C., then n-butyllithium (1.6 M in hexane, 15.1 ml, 24.2 mmol) was added and the mixture was stirred for 1 hour. A solution of ((R)-1-iodomethyl-propyl)-benzene (6.30 g, 24.2 mmol) in tetrahydrofuran (30 ml) was added dropwise over 30 min and the mixture was stirred overnight while being allowed to warm slowly from -70° C. to room temperature. The reaction was quenched by addition of saturated aqueous ammonium chloride solution and the mixture was extracted with ether. The organic layer was separated, washed with saturated brine, then dried over Na2SO4 and concentrated in vacuo. The residue was purified by column chromatography (SiO2, heptane/EtOAc) to yield a light yellow oil (4.69 g, 64percent); MS (ISP): 317.0 ([M+H]+).

The synthetic route of 109838-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; HOFFMANN-LA ROCHE INC.; Hoener, Marius; Raab, Susanne; Risterucci, Celine; Sewing, Sabine; US9132136; (2015); B2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 33332-29-5, 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 33332-29-5 as follows.

Step 2: Preparation of 2,5-dichloropyrazine; 5-Chloropyrazin-2-amine (5.0 g, 38.6 mmol) was dissolved in acetonitrile (77 ml) under a balloon of N2. The copper(I) chloride (5.7 g, 57.9 mmol) and copper(ET) chloride (7.8 g, 57.9 mmol) were added and the slurry cooled to -1O 0C with an ice:acetone bath. t-Butyl nitrite (9.15g, 89 mmol, 90percent) was added dropwise and the solution allowed to warm to RT. The solution was stirred for 30 minutes until rapid gas evolution ceased. The mixture was heated to 65 0C for 2.5 hours. The mixture was cooled to RT and filtered through a 1.5 inch pad of celilte packed into a 465 ml frit. The pad was washed with DCM (200 ml x 4), the wash fractions containing the desired material combined, filtered, and concentrated in vacuo. The residue was purified by chromatography on silica gel with 2percent etheI.euro.pentane to yield the title compound.

According to the analysis of related databases, 33332-29-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MERCK & CO., INC.; WO2008/85316; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 109838-85-9,Some common heterocyclic compound, 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, molecular formula is C9H16N2O2, 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.

Synthesis of Intermediate Compound Int-8d(i?)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine (Int-8c, 25 g,135.7 mmol) and dried THF (500 mL) were added to a dried 1 -liter flask which was cooled to -78 °C and maintained under nitrogen atmosphere. A solution of 2.5 M n-BuLi in hexane (54 mL, 135 mmol) was added slowly via a syringe. The resulting solution was allowed to stir at the cold temperature for 30 minutes before addition of Int-8b (90.5 g, 266.2 mmol) via a syringe. The reaction mixture was continued to stir for 4 hours and warmed to room temperature gradually over a period of 1 hour. After addition of water (100 mL) and diethyl ether (1.0 liter), the solution was washed with water (2 x 200 mL) and dried over sodium sulfate. The solution was concentrated in vacuo and the residue obtained was purified using a 330 g ISCO silica column on Combi-Flash with 0-1percent ether in hexanes as an eluent to provide Int-8d as an oil (18.5 g, 35percent).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, its application will become more common.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DWYER, Michael, P.; KEERTIKAR, Kartik, M.; ZENG, Qingbei; MAZZOLA, Robert, D., Jr.; YU, Wensheng; TANG, Haiqun; KIM, Seong Heon; TONG, Ling; ROSENBLUM, Stuart, B.; KOZLOWSKI, Joseph, A.; NAIR, Anilkumar Gopinadhan; WO2013/39876; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem