Tag: M.W=100-200

55557-52-3, A common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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.

Step-1: (0930) Preparation of (3-chloropyrazin-2-yl)methanamine hydrochloride: (0931) [00352] To a solution of 3-chloropyrazine-2-carbonitrile (10 g) in acetic acid (100 mL) was added Raney Nickel (50% slurry in water, 10 g). The resulting mixture was stirred under 4 bar hydrogen pressure at room temperature for 15 h. The reaction mixture was filtered through celite and the filtrate was concentrated under reduced pressure and co-evaporated with toluene. The remaining brown solid was dissolved in ethyl acetate at 50 C and cooled on an ice-bath. 4M hydrochloric acid in dioxane (50 mL) was added and the reaction mixture was allowed to stir at room temperature for 18 h. The precipitate formed was collected by filtration, washed with diethyl ether and dried under reduced pressure. The product brown solid obtained was dissolved in methanol at 60 C and filtered. The filtrate was partially concentrated, cooled to room temperature and diethyl ether (500 mL) was added. The mixture was allowed to stir at room temperature 18 h. The solids formed were collected by filtration, washed with diethyl ether and dried under reduced pressure to afford the title compound (3-chloropyrazin-2- yl)methanamine hydrochloride (7.67 g, crude) as a brown solid. Calculated (M+H): 144.03; Found (M+H): 144.0

The synthetic route of 55557-52-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; LUC THERAPEUTICS; ANDERSON, David, R.; VOLKMANN, Robert, A.; MENNITE, Frank, S.; FANGER, Christopher; (390 pag.)WO2017/100591; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

19745-07-4, 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 19745-07-4 as follows.

A mixture of A-63 (10.00 g, 67.12 mmol) in EtOH (80 mL) was stirred under N2 at 80 C for 16 hours. The mixture was concentrated to give the crude product, which was triturated from H20 (20 mL) to give A-64 (1.60 g, 11.07 mmol) as a solid. 1H NMR (400MHz, CDCI3) _ = 8.10 – 8.01 (m, 2H), 6.03 (br s, 1H), 3.85 (br s, 2H).

According to the analysis of related databases, 2,5-Dichloropyrazine, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PRAXIS PRECISION MEDICINES, INC.; REDDY, Kiran; MARTINEZ BOTELLA, Gabriel; GRIFFIN, Andrew, Mark; MARRON, Brian, Edward; (364 pag.)WO2018/98499; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, molecular formula is C6H4BrN3, 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. 875781-43-4

Step 1: 2-Bromo-5H-pyrrolo[2,3-b]pyrazine (1.98 g, 10.0 mmol) was dissolved in DMF (33 mL) and cooled down to 0 C. NaH (60%, 0.480 g, 12.0 mmol) was added slowly. After the addition was complete stirring was continued for 30 minutes at 0 C. (2-Chloromethoxy-ethyl)-trimethyl-silane (2.1 mL, 12.0 mmol) was added and the reaction mixture was allowed to warm up overnight. The reaction was quenched with H2O. The aqueous layer was extracted with EtOAc. The organic layer was dried (MgSO4), filtered, concentrated, and purified by SiO2 chromatography (150 g SiO2, hexanes/EtOAc 0-35% EtOAc) to give 2.81 g of 2-bromo-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine as a yellow liquid (86% yield).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 875781-43-4, its application will become more common.

Reference:
Patent; Bamberg, Joe Timothy; Hermann, Johannes Cornellius; Lemoine, Remy; Soth, Michael; US2010/144745; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

356783-16-9, name is 3,6-Dichloropyrazine-2-carbonitrile, 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. 356783-16-9

A mixture of 8 (2.6 g, 15.0 mmol), KF (5.23 g, 90.0 mmol), tetrabutylammonium bromide (1.93 g, 6.0 mmol) was predried under vacuum over phosphorus pentoxide. The mixture was charged in a polytetrafluoroethylene bottle followedby the addition of dried DMSO (20 mL), and heated at 60 C for 2.5-3 h. The reaction mixture was cooled to room temperature, treated with water (80 mL) and extracted with diethyl ether (100 mL). The organic layer was washed with water (3 ¡Á 25 mL), dried over Na2SO4, and purified by chromatography on silica gel with PE/EA (50:1-10:1) as eluent to give 9 as a white solid (1.27 g, yield 60%). 3,6-Difluoropyrazine-2-carbonitrile (9) Yield: 60%. white solid, M.p.: 58-60 C (Lit. 56-57 C, Li 2017). 1H NMR (400 MHz, CDCl3)delta 8.35 (dd, J = 8.1,1.4 Hz, 1H). 13C NMR (125 MHz, CDCl3):delta 159.73-157.69(d, J = 255 Hz), 157.64-155.62 (d, J = 252.5 Hz), 135.09 (dd, J = 41.6, 11.0 Hz), 114.04 (d, J = 35.8 Hz), 110.62 (d,J = 9.1 Hz). EI-MS m/z: 141 (M+, 100), 122 (M+, -F, 50),96 (M+, -F, -CN, 50).

Statistics shows that 356783-16-9 is playing an increasingly important role. we look forward to future research findings about 3,6-Dichloropyrazine-2-carbonitrile.

Reference:
Article; Guo, Qi; Xu, Mingshuo; Guo, Shuang; Zhu, Fuqiang; Xie, Yuanchao; Shen, Jingshan; Chemical Papers; vol. 73; 5; (2019); p. 1043 – 1051;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common compound: 113305-94-5, name is 5-Aminopyrazine-2-carbonitrile, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 113305-94-5

A solution of thiophosgene (1.86 g, 15 mmol) in THF (4 mL) is added dropwise to a solution of 5-aminopyrazine-2-carbonitrile (1.20 g, 10 mmol) and pyridine (2 mL) in CH2Cl2 (200 mL) and THF (25 mL) at room temperature. The reaction mixture is stirred at room temperature for 3 h. The mixture is concentrated and the crude product is diluted with ethyl acetate, filtered and concentrated to give the title compound.

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, 113305-94-5, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Farouz, Francine S.; Holcomb, Ryan Coatsworth; Kasar, Ramesh; Myers, Steven Scott; US2011/144126; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

23688-89-3, Adding some certain compound to certain chemical reactions, such as: 23688-89-3, name is 6-Chloropyrazine-2-carboxylic acid, 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 23688-89-3.

To a 100 ml round bottom flask, 6-chloropyrazine-2-carboxylic acid (Ig, 6.31 mmol) was suspended in dry CH2Cl2 (30ml). Oxalyl chloride (3.78 ml, 7.57 mmol) was added along with a few drop of DMF, the mixture was stirred at room temperature for 12 hrs, N, O- Dimethylhydroxylamine hydrochloride (0.800 g, 8.20 mmol) was added, the resulting mixture was cooled down to 5C, TEA (2.64 ml, 18.92 mmol) was added via a droping funal, the reaction mixture was stirred at room temperature for 30 minutes, filtered and the filter cake was washed with EtOAc, the combinded filtrate was washed with saturated sodium bicarbonate and brine, concentrated to an oil, purified on silica gel with Hexanes/EtOAc solventsto give product (1.06g). MS (ES) MH+: 202 for C7H8ClN3O2

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 23688-89-3.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; BARVIAN, Kevin; BASARAB, Gregory, Steven; GOWRAVARAM, Madhusudhan, Reddy; HAUCK, Sheila, Irene; ZHOU, Fei; WO2010/43893; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6863-73-6, A common compound: 6863-73-6, name is 3-Chloropyrazin-2-amine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

EXAMPLE 1; Tert-butyl 4-(8-(2-fluoro-4-(methylsulfonyl)phenylamino)imidazo[l,2- a]pyrazin-3-yl)-5,6-dihydropyridine-l(2H)-carboxylateStep 1: 8-Chloroimidazo[l,2-a]pyrazine[0313] 3-chloropyrazin-2-amine (21.0 g, 161.54 mmol, 1.00 equiv) was dissolved in isopropyl alcohol (200 mL) in a 500 mL round-bottom flask equipped with a reflux condenser. To this solution was added 2-bromo-l,l-diethoxyethane (160.3 g, 813.71 mmol, 5.00 equiv) in small portions over 10 minutes. The resulting mixture was then allowed to reflux for 2 hours in an oil bath. The reaction was monitored by TLC (EtOAc/PE = 1:1). The mixture was cooled down to room temperature and filtered off to give a yellow cake. The solid was added to a saturated solution of NaHCC>;3 (200 mL) and DCM (IL). Aqueous layer was separated from organic phase and re-extracted with DCM (2x 250 mL). The combined organics were dried over MgSO4, filtered and evaporated to dryness affording 8-chloroimidazo[l,2-a]pyrazine (25 g) as a yellow solid.

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-Chloropyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; KALYPSYS, INC.; KAHRAMAN, Mehmet; SMITH, Nicholas, D.; BONNEFOUS, Celine; NOBLE, Stewart, A.; PAYNE, Joseph, E.; WO2010/88518; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common compound: 5521-58-4, name is 5-Methylpyrazin-2-amine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 5521-58-4

1-Chloro-N,N,2-trimethyl-l-propenylamine (0.86 g, 6.56 mmol) was added to a solution of 3- [4-(azetidin-1-ylcarbonyl)-2-fluorophenoxy]-5-(( 15)-2- {(tert-butyl( dimethyl)silyl]oxy} -1- methylethoxy)benzoic acid (3 g, 5.96 mmol) in DCM (100 mL) and stirred at RT for Ihour. 2- Amino-5-methylpyrazine (1.3 g, 11.9 mmol) and pyridine (0.94 mL, 11.9 mmol) were added and the reaction stirred for a further 30 mins. The solvent was removed in vacuo. Water (100 mL) was added and the mixture extracted with ethyl acetate (3 x 50 mL). The extracts were combined and washed with water (100 mL), brine (100 mL), dried (MgS04), filtered, and evaporated in vacuo to give the crude product which was chromatographed on silica, eluting with a gradient of 50-100% ethyl acetate in isohexane, to give the desired compound (3.6 g). ?H NMR No. (CDC13): 0.00 (s, 3H), 0.03 (s, 3H), 0.81 (s, 9H), 1.30 (d, 3H), 2.32 (quin, 2H), 2.51 (s, 3H), 3.60-3.80 (m, 2H), 4.20-4.39 (brm, 4H), 4.45 (m, 1H), 6.75 (m, 1H), 7.03 (d, 2H), 7.21 (s, 1 H), 7.40 (d, 1 H), 7.50 (d, 1 H), 8.10 (s, 1 H), 8.27 (s, 1 H), 9.48 (s, 1 H). m/z 595 (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, 5521-58-4, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2005/121110; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

4858-85-9, 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 4858-85-9 as follows.

2,3-Dichloropyrazine A-1 (15 g; 100.68 mmol) and hydrazine hydrate 65 % (15.509 ml; 201.37 mmol) are dissolved in 45 ml ethanol and stirred for 1 h at 80 C. While cooling down, a precipitate is formed. It is slurred up with a small amount of water and filtered off. It is washed with water and then dried to afford the product. Yield: 93% (13.6 g; 94.07mmol) HPLC-MS: (M+H)+ = 145/147; tRet = 0.34 min; method FECB5

According to the analysis of related databases, 2,3-Dichloropyrazine, the application of this compound in the production field has become more and more popular.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; ENGELHARDT, Harald; WO2015/67770; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

33332-29-5, 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. 33332-29-5, name is 2-Amino-5-chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Description 5 2,5-Dichloropyrazine (D5); 5-Chloro-2-pyrazinamine (D4) (753 mg, 5.81 mmol) was dissolved in concentrated hydrochloric acid (8 ml), cooled in an ice-acetone bath and treated with a solution of sodium nitrite (822 mg, 11.9 mmol) in water (6 ml) dropwise over a period of 1 hour. The mixture was transferred to an ice-water bath and left to stir for 1 hour. The mixture was allowed to warm to room temperature over 2 hours, neutralised by addition of an aqueous 50% sodium hydroxide solution and extracted with dichloromethane (x 4). The dichloromethane layers were combined, dried under magnesium sulfate and evaporated. The resulting residue was purified by Biotage column chromatography eluting with 10% ethyl acetate in pentane to afford the title compound (112 mg). ?H NMR (CDCI3) 8.40 (2H, s).

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; GLAXO GROUP LIMITED; WO2005/123723; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem