Tag: M.W=100-200

These common heterocyclic compound, 22047-25-2, name is Acetylpyrazine, 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

General procedure: A 2-neck round bottom flask attached with calcium chloride guard tube was charged with MeOH (30mL). Then, 2-acetylpyrazine (1.47g, 2mmol) followed by KOH pellets (0.675g, 2mmol) were added and initiated magnetic stirring. To this mixture, distilled water (2mL) was added and continued stirring for 10min. Now, the resulting solution was added the respective n,n?,n?-trimethoxyphenyl benzaldehydes (1.0g, 1mmol) under stirring at room temperature slowly and then 6mL of ammonia solution was added. The reaction mixture was stirred further for 4h. The reaction was monitored by TLC. On completion of reaction by TLC, the reaction mass was filtered and washed with methanol (3×10 mL) and then diethyl ether (3×10 mL) to obtain a white precipitate of respective compounds. Each of the above precipitates was recrystallised in a mixture of CHCl3 and MeOH (1:1) at room temperature for 48h. The resulting colourless single crystals of 1-3 were collected by filtration.

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

Reference:
Article; Ramesh; Sharath Kumar; Raghavendra Kumar; Suchetan; Devaraja; Sabine, Foro; Nagaraju; Journal of Molecular Structure; vol. 1200; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 5521-55-1, 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. 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows.

1) 5-Methylpyrazine-2-carboxylic acid N-methoxy-N-methylamide Triethylamine (28.9 mL) was added at room temperature to 5-methylpyrazine-2-carboxylic acid (13.0 g), N,O-dimethylhydroxylamine hydrochloride (10.1 g), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (19.8 g), and 1-hydroxybenzotriazole (14.0 g) in N,N-dimethylformamide (130 mL), followed by stirring for 63 hours. The reaction mixture was partitioned between water and ethyl acetate. The organic layer was dried over sodium sulfate anhydrate. After a filtration step, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (hexane – ethyl acetate), to thereby give 5-methylpyrazine-2-carboxylic acid N-methoxy-N-methylamide as a solid product (12.3 g, 72%). 1H-NMR(400MHz,CDCl3)delta:2.63(3H,s), 3.41(3H,s), 3.74(3H,s), 8.46(1H,s), 8.82(1H,s). FAB-MS m/z:182(M+H)+.

The chemical industry reduces the impact on the environment during synthesis 5-Methylpyrazine-2-carboxylic acid. I believe this compound will play a more active role in future production and life.

Reference:
Patent; DAIICHI PHARMACEUTICAL CO., LTD.; EP1762568; (2007); 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. 27398-39-6, name is 3-Chloropyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C5H3ClN2O2

2.3 3-Chloro-pyrazine-2-carboxylic acid{2-[2-(2,5-difluoro-phenyl)-ethoxy]-1-imino-ethyl}-amide; 2-[2-(2,5-Difluoro-phenyl)-ethoxy]-acetamidine hydrochloride (158 mg, 0.631 mmol) was dissolved in DMF (3 ml) and 3-chloro-2-pyrazine-carboxylic acid (100 mg, 0.631 mmol), TBTU (213 mg, 0.662 mmol) and DIPEA (565 mul, 3.15 mmol) were added. The reaction mixture was stirred at ambient temperature for 4.5 h. Then water was added and the mixture was extracted three times with CH2Cl2. The combined organic extracts were washed with water and brine, dried (Na2SO4) and evaporated. The crude title compound (195 mg, brown gum) was used for the next reaction step without further purification. MS: m/e=355.2 [M+H+].

According to the analysis of related databases, 27398-39-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Conte, Aurelia; Dehmlow, Henrietta; Grether, Uwe; Kratochwil, Nicole A.; Kuehne, Holger; Narquizian, Robert; Panousis, Constantinos G.; Peters, Jens-Uwe; Ricklin, Fabienne; US2008/234277; (2008); 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. 6705-33-5, name is Pyrazin-2-ylmethanol, This compound has unique chemical properties. The synthetic route is as follows., Safety of Pyrazin-2-ylmethanol

Step A: 3-chloro-4-(2-pyrazinemethoxyl)-nitrobenzene (compound 22.1).[0168] To a solution of 2-chloro-l-fluoro-4-mtro-benzene (875 mg, 5.0 mmol) in dryAcetone (10.0 ml) was added l.Og Of K2CO3 and 545mg of 2- pyrazinylmethanol(5.0mmol). The reaction mixture was then stirred at 650C overnight. Filtration and concentration gave a solid which was recrystallized to give the desired product as a red 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 6705-33-5.

Reference:
Patent; KANIONUSA INC.; SHEN, Wang; ZHANG, Aimin; FAN, Junfa; ZHENG, Xiaoling; WO2011/2523; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 939412-86-9, The chemical industry reduces the impact on the environment during synthesis 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, I believe this compound will play a more active role in future production and life.

(3-chloropyrazin-2-yl)methanamine.hydrochloride (5 g, 27.8 mmol) and triethylamine (11.61 mL, 83 mmol) dichloromethane (80 mL) was added acetic anhydride (2.63 mL, 27.8 mmol) and the reaction mixture was stirred at 0C for 30 min. The mixture was filtered and the filtrate concentrated in vacuo. The product was purified using silica gel chromatography (ethylacetate/ethanol = 5/1 v/v%) to give 4.45 g of N-((3-chloropyrazin-2-yl)methyl)acetamide (88%).

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-yl)methanamine hydrochloride, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MSD Oss B.V.; Man, de, Adrianus, Petrus, Antonius; Sterrenburg, Jan-Gerard; Raaijmakers, Hans C.A.; Kaptein, Allard; Oubrie, Arthur A.; Rewinkel, Johannes, Bernardus, Maria; Jans, Christiaan, Gerardus, Johannes, Maria; Wijkmans, Jacobus C.H.M.; Barf, Tjeerd A.; Gao, Xiaolei; Boga, Sobhana Babu; Yao, Xin; Zhu, Hugh Y.; Cooper, Allen B.; Kim, Ronald M.; EP2548877; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products 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: The procedure for the synthesis of the tetrazole 2a is representative. A mixture of sodium azide (0.39 g 0.0060 mol), urea (0.36 g, 0.0060 mol) and water (2.5 mL) was taken in a round-bottom flask and stirred at 60 C for 1 h. Charged benzonitrile 1a (0.5 g 0.0048 mol), acetic acid(0.5 mL) and DMF (2.5mL) at 60 C and heat to 110C stirred for 8 h. After completion of the reaction (as indicated by TLC), the reaction mixture was cooled to room temperature and diluted the reaction mass with water (2.5 mL)and ethyl acetate (5.0 mL) at 25-35 C. Add 5N aqueous hydrochloric acid (2.5 mL) at 25-35 C. Stirred for 20- 30 min, the resultant organic layer was separated and the aqueous layer was extracted with ethyl acetate (2.5 mL). The combined organic layer was washed with 40 % aq.NaCl solution (2.5 mL) and dried over anhydrous Na2SO4 and concentrated to give a crude product, which was isolated using chilled water after 3-4 h maintenance, and eventually filtered off to give 0.67 g (95%) of an off-white solid.

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

Reference:
Article; Yakambram; Jaya Shree; Srinivasula Reddy; Satyanarayana; Naveen; Bandichhor, Rakeshwar; Tetrahedron Letters; vol. 59; 5; (2018); p. 445 – 449;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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

2-Bromo-5H-pyrrolo [2,3-b] pyrazine (300 mg, 1.52 mmol) was dissolved in N, N- dimethylformamide (8 mL)Sodium hydride (60%, 91.3 mg, 2.28 mmol) was added under ice bath and stirring continued at this temperature. After 30 min 2- (trimethylsilyl) ethoxymethyl chloride (404 muL, 2.26 mmol ),Stir at room temperature for 12h. Quenched with water (20 mL)The mixture was extracted with dichloromethane (30 mL × 2) and concentrated for column chromatography (eluent: PE / EtOAc (v / v) = 5/1) to give 270 mg of a yellow oil. Yield: 54.3%.

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; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Liu Bing; Bai Shun; Zhou Youbo; Yang Tiping; He Wei; Zhang Yingjun; Zheng Changchun; (103 pag.)CN106749268; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 59489-71-3, A common heterocyclic compound, 59489-71-3, name is 2-Amino-5-bromopyrazine, molecular formula is C4H4BrN3, 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.

To 5-bromo-pyrazin-2-ylamine (0.46 g, 2.6 mmol), NaCN (1.3 g, 26 mmol) and CuCN (2.74 g, 26 mmol) in a nitrogen-purged vial was added DMF (10 mL). The resulting mixture was heated at 120 C. over the weekend. After cooling down to room temperature, DMF was removed under high vacuum. The residue was partitioned between EtOAc and water. The organic extracts were combined, dried and concentrated to give the crude product as a yellow solid (0.296 g, 93%), which was used in the subsequent reaction without further purification.

The synthetic route of 59489-71-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Kelly, Martha; Lee, Younghee; Liu, Bin; Fujimoto, Ted; Freundlich, Joel; Dorsey, Bruce D.; Flynn, Gary A.; Husain, Arifa; US2006/270686; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application 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.

5-CHLORO-2-PYRAZINAMINE (D47, Step 1) (2.41 g, 18.6 MMOL) was dissolved in concentrated hydrochloric acid (24 ML), cooled in an ice-acetone bath and treated with a solution of sodium nitrite (2.63 g, 38.1 MMOL) in water (18 ML) dropwise over a period of 1 hour. The mixture was cooled in an ice-water bath and left to stir for 1 hour. The mixture was allowed to warm to room temperature over 1 hour, neutralised by addition of sodium hydroxide solution (2M) and extracted with dichloromethane. The DICHLOROMETHANE layers were combined, dried under magnesium sulfate and evaporated in vacuo. The resulting residue was purified by column chromatography eluting with a mixture of ethyl acetate: pentane (1: 9) to afford the title compound (0.33 g);’H NMR (CDCI3) 8.40 (2H, s).

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; GLAXO GROUP LIMITED; WO2004/56369; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, 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. name: 2,6-Dichloropyrazine

Preparation of compound 16a: 3,5-dichloro-2-methylpyrazineTo a solution of n-BuLi (78 mL, 0.195 mol) in dry THF (1.5 L) was added TMP (27.5 g, 0.195 mol) at -65 0C. After the addition, the mixture was warmed to 0 0C and stirred for 30 min at this temperature, the reaction mixture was then re-cooled to -78 0C and 2,6-dichloropyrazine (20 g, 0.13 mol) in THF (50 mL) was added into the mixture dropwise. The mixture was stirred for 30 min at -78 0C, then CH3I (65 g, 0.68 mol) was added and the reaction mixture was slowly warmed to rt and stirred for 3 h. The mixture was concentrated and diluted with H2O (300 ml_), extracted with DCM (4×100 ml_). The combined organic layer was washed with saturated NH4CI aqueous and water, dried over Na2SO4, concentrated and the residue was purified by chromatography which gave the title compound 16a (10 g, 47.6%).

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

Reference:
Patent; PFIZER INC.; NINKOVIC, Sacha; BRAGANZA, John Frederick; COLLINS, Michael Raymond; KATH, John Charles; LI, Hui; RICHTER, Daniel Tyler; WO2010/16005; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem