Tag: M.W=200-300

These common heterocyclic compound, 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, 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. Formula: C6H7ClN4O2

General procedure: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate 2 (1 eq.) was combined with K2CO3 (10 eq.), the appropriate (het)aryl boronic acid (1.5 eq.) and Pd(PPh3)4 (5 mol%) in a two-neck round bottom flask. The flask was connected to a condenser and purged with nitrogen. A 4:1 mixture of anhydrous toluene: MeOH (60 mL) was added via syringe and the reaction mixture was heated at reflux for 0.5-18 h. The mixture was allowed to cool to room temperature and filtered through Celite (10 x 3 cm, eluting with 3 x 20 mL EtOAc). The filtrate was evaporated to dryness and the residue purified by silica gel flash column chromatography using EtOAc/pet spirit.

The synthetic route of Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Article; Buckley, Benjamin J.; Majed, Hiwa; Aboelela, Ashraf; Minaei, Elahe; Jiang, Longguang; Fildes, Karen; Cheung, Chen-Yi; Johnson, Darren; Bachovchin, Daniel; Cook, Gregory M.; Huang, Mingdong; Ranson, Marie; Kelso, Michael J.; Bioorganic and Medicinal Chemistry Letters; vol. 29; 24; (2019);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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 24241-18-7, Computed Properties of C4H3Br2N3

To a stirred solution of 2-amino-3,5-dibrompyrazine (20 g, 79 mmol) in dimethylcarbonate (133 mL) at rt was added ethyl 3-bromo-2-oxopropanoate (17.14 g, 79 mmol) in one portion. After stirring at 110 C. for 3 h, the solution was stirred at rt overnight. Water and DCM were added and the aqueous phase was extracted with DCM. After washing of the organic phase with water, drying over Na2(SO4) and filtration the organic phase was evaporated. Flash chromatography yielded 13.95 g (50.6%) ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylate: 1H-NMR (300 MHz, CDCl3: delta=8.30 (s, 1H), 8.27 (s, 1H), 4.48 (q, 2H), 1.43 (tr, 3H) ppm.

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; BAYER INTELLECTUAL PROPERTY GMBH; Koppitz, Marcus; Klar, Ulrich; Jautelat, Rolf; Kosemund, Dirk; Bohlmann, Rolf; Bader, Benjamin; Lienau, Philip; Siemeister, Gerhard; US2013/267527; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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 24241-18-7, Recommanded Product: 2-Amino-3,5-dibromopyrazine

Zinc powder (235 mg, 3.6 mmol) and iodine (12 mg) were mixed under nitrogen and DMF was added. The mixture was stirred at room temperature until the color of the iodine disappeared. Benzyl bromide (0.57 mg, 3 mmol) was then added and the mixture was stirred at 80 ° C for about 3 hours. After the reaction mixture had cooled to room temperature, 2-amino-3,5 dibromopyrazine (506 mg, 2 mmol) and triphenylphosphine palladium dichloride (70 mg, 0.1 mmol) were added. Reaction at room temperature for 24 hours. The reaction mixture was filtered through celite and extracted with ethyl acetate. The ethyl acetate phase was washed with saturated sodium chloride solution. The ethyl acetate phase was dried over anhydrous sodium sulfate, filtered and purified by silica gel column chromatography on 200-300 mesh, The intermediate compound 1-1 was 313 mg of yellow solid with a yield of 59percent.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-3,5-dibromopyrazine, and friends who are interested can also refer to it.

Reference:
Patent; Shandong University; Li Minyong; Du Lvpei; Jiang Tianyu; (37 pag.)CN105968114; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 25710-18-3, A common heterocyclic compound, 25710-18-3, name is 2,3-Dichloropyrido[2,3-b]pyrazine, molecular formula is C7H3Cl2N3, 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 slurry of 2,3-Dichloropyrido[2,3-b]pyrazine (Intermediate F step 2) (500 mg, 2.500 mmol), 3- fluoro-4-methylphenylboronic acid (847 mg, 5.50 mmol),tetrakis(triphenylphosphine)palladium(0) (173 mg, 0.150 mmol) and potassium carbonate (1520 mg, 1 1 .00 mmol) in dioxane (20 ml) was degassed by bubbling nitrogen through (x3). The reaction mixture was heated using microwave radiation under nitrogen at 150 °C for 4h. The resulting mixture was partitioned between EtOAc and water. The organic portion was separated, dried (sodium sulphate), filtered and concentrated in vacuo. The crude product was purified by chromatography on silica eluting with 0-3percent THF in DCM to afford the title compound;LCMS; Rt 1 .28 mins MS m/z 348 [M+H]+ Method 2minl_C_v003

The synthetic route of 25710-18-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NOVARTIS AG; CHARLTON, Steven, John; LEBLANC, Catherine; MCKEOWN, Stephen, Carl; WO2012/7539; (2012); A1;,
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 63744-22-9 as follows. Recommanded Product: 63744-22-9

Intermediate Example 16-Bromo-8-(methylsulfanyl)imidazo 1 ,2-a]pyrazineA mixture of 61 .0 g (220 mmol) 6,8-dibromoimidazo[1 ,2-a]pyrazine (CAS 63744- 22-9), 610 mL methanol and 30.2 g sodium methanethiolate was stirred at 23 C for 16 hours, poured into 6 L water and cooled until a precipitate had formed. The product was filtered off and dried at 60C to give 38.5 g (72%) of the title compound which was used without further purification.

According to the analysis of related databases, 63744-22-9, the application of this compound in the production field has become more and more popular.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; KLAR, Ulrich; KOPPITZ, Marcus; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; PRECHTL, Stefan; NGUYEN, Duy; SCOTT, William; WO2011/113862; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 1053656-22-6,Some common heterocyclic compound, 1053656-22-6, name is 7-tert-Butyl 2-ethyl 5,6-dihydroimidazo[1,2-a]pyrazine-2,7(8H)-dicarboxylate, molecular formula is C14H21N3O4, 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.

LiOH.H2O (8.8 mmol, 4.0 equiv.) was added at 0 C. to a solution of 7-tert-butyl 2-ethyl-5,6-dihydroimidazo[1,2-a]pyrazine-2,7(8H)-dicarboxylate (2.2 mmol, 1.0 equiv.) in methanol/water (2.5:1, 35 ml), and the mixture was then stirred for 2 h at 25 C. When the reaction was complete (TLC monitoring), the methanol was removed in vacuo, the residue was diluted with water (40 ml), and extraction with ethyl acetate (2×40 ml) was carried out. The aqueous phase was then adjusted to pH 2-3 with 1N HCl solution, and the resulting solid was filtered out. The solid was taken up in toluene, and the solvent was then removed in vacuo (2×) to yield the desired product in the form of a white solid. Yield: 68%.

The synthetic route of 1053656-22-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Gruenenthal GmbH; US2010/234340; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 5900-13-0, 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. 5900-13-0, name is 5-Bromo-3-methoxypyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Toa solution of 5-bromo-3-methoxypyrazin-2-amine (500 mg, 2.45 mmol) in pyridine(5 mL) at room temperature was added 3-chlorophenyl)methanesulfonyl chloride(552 mg, 2.45 mol) over 5 min. The mixture was stirred 10 mins, the pyridineevaporated, then DCM (60 mL) and water (10 mL) was added. The phases wereseparated and the organic phase was washed with brine (5 mL), dried (Na2SC>4),the mixture filtered and the filtrate evaporated to dryness to afford an orangeoil which was chromatographed on silica (Heptane: EtOAc 1 :1) to afford thetitle compound as a light brown solid (483 mg, 48%); m z=393.7, 395.7 (MH)+.

The synthetic route of 5-Bromo-3-methoxypyrazin-2-amine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ACTIVE BIOTECH AB; FRITZSON, Ingela; LIBERG, David; EAST, Stephen; MACKINNON, Colin; PREVOST, Natacha; WO2014/184234; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 51171-02-9, name is Methyl 3-Bromo-2-pyrazinecarboxylate, 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. category: Pyrazines

A solution of 3-bromopyrazine-2-carboxylic acid methyl ester (0.10 g, 0 45 mmol), 2- t?tylsulfanylethylamine (0 29 g, 0 90 mmol), and triethylamine (0.OS mL, 0.44 mmol) in acetonitrile (5 mL) was heated to reflux for 18 h under argon. The mixture was concentrated under reduced pressure and purified by column chromatography (3:1 Hex. EtOAc), yielding 0.058 g (28%) of the desired product. 1H NMR (400 MHz1 CD2CI2) delta 7.95 (s, 1H), 8.44 (s, 1 H), 8.31 (s, 1H), 7 57.18 (m, 15H), 4 20 (s, 3H), 3.36(t, 2H), 2.50 (t, 2H).

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

Reference:
Patent; BAYER PHARMACEUTICALS CORPORATION; WO2006/49681; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 143591-61-1,Some common heterocyclic compound, 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, molecular formula is C6H3BrClN3, 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.

Example 2 2-(3-Bromo-imidazo[1,2-a]pyrazin-8-ylamino)-ethanol 3-Bromo-8-chloro-imidazo[1,2-a]pyrazine (0.70 g, 3.0 mmol) (from Example 1 supra) was stirred in nBuOH (10 mL) and ethanolamine (0.22 mL, 3.65 mmol) followed by Hunig’s base (1.04 mL, 6.0 mmol) Reaction mixture was then heated at 100 C. overnight. The mixture was concentrated to dryness and water was added (150 mL) followed by a saturated aqueous solution of NaHCO3 (50 mL). The reaction was then extracted with EtOAc (3*20 mL) and the organic phases were combined, washed with water (2*20 mL), dried over MgSO4 and concentrated to dryness to give 2-(3-bromo-imidazo[1,2-a]pyrazin-8-ylamino)-ethanol. (Yield 0.59 g, 77%). 1H (400 MHz; DMSO-d6) delta 3.52-3.56 (2H, m), 3.58-3.62 (2H, m), 4.79 (1H, t, J=5.4 Hz), 7.42 (2H, d, J=5 Hz), 7.56 (1H, d, J=5 Hz), 7.66 (1H, s).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, its application will become more common.

Reference:
Patent; Luk, Kin-Chun; Soth, Michael; US2012/238564; (2012); 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. 221136-66-9, name is Ethyl 2-(3-bromo-6-methyl-2-oxopyrazin-1(2H)-yl)acetate, A new synthetic method of this compound is introduced below., SDS of cas: 221136-66-9

Example 8 r3-(2,2-Difluoro-2-phenyl-ethylamino)-6-methyl-2-oxo-2H-pyrazin-1-vn- acetic acid ethyl ester(3-Bromo-6-methyl-2-oxo-2H-pyrazin-1 -yl)-acetic acid ethyl ester was reacted with 2,2-difluoro-2-phenyl-ethylamine in the presence of a base, at elevated temperature, to yield the title compound as shown in the Scheme above. Table 5 below lists the reagent amounts, base and temperature combinations applied to this reaction, as well as yield.

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; JANSSEN PHARMACEUTICA, N.V.; WO2007/146553; (2007); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem