Month: September 2021

Application of 4858-85-9, A common heterocyclic compound, 4858-85-9, name is 2,3-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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.

2,3-dichloro-pyrazine (25 g) was dissolved in ethanol (500 mL),Hydrazine monohydrate (16.7 mL) was added, And the mixture was stirred under reflux for 1 hour and a half. Water was added to the reaction solution, and the precipitated solid was dried under reduced pressure after filtering off the resulting solid to give the title compound as white crystals by recrystallization from ethanol (18.12g, 74%).

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; TAIHO PHARMACEUTICAL COMPANY LIMITED; MINAMIGUCHI, KAZUHISA; OKAJIMA, SHIGEO; AOKI, SHINICHI; ASAI, MASANORI; ASAI, TAKAHIRO; YAMANAKA, HIROYOSHI; DOHI, SUGURU; (149 pag.)JP5851663; (2016); B1;,
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. 74290-65-6, name is 3-Bromo-5-methylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. SDS of cas: 74290-65-6

(ii) 2-Amino-3-bromo-5-methylpyrazine (0.374 g) was added to a freshly prepared solution of sodium methoxide in methanol (made by addition of sodium (0.115 g) to methanol (6 ml). The reaction mixture was heated under reflux for 18 hours, cooled to ambient temperature and the solvent removed by evaporation. Water (5 ml) was added to the residue and extracted with dichloromethane (3*20 ml). The combined organic extracts were dried (MgSO4) and the solvent removed by evaporation. The residue was purified by chromatography on silica gel, eluding with dichloromethane to give 2-amino-3-methoxy-5-methylpyrazine as a white crystalline solid (0.208 g, 75%), m.p. 67-69 C.; mass spectrum (+ve CI): 140 (M+H)+.

The synthetic route of 74290-65-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Zeneca Ltd.; US5668137; (1997); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1286754-14-0,Some common heterocyclic compound, 1286754-14-0, name is Ethyl imidazo[1,2-a]pyrazine-3-carboxylate, molecular formula is C9H9N3O2, 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.

The imidazo [1,2 – the a] pyrazine -3 – carboxylic acid ethyl ester (780 mg, 4 . 08 mmol) is dissolved under stirring 20 ml in tetrahydrofuran, then add 10% palladium carbon 400 mg, hydrogen under the protection of the 35 C stirring 12 hours, the reaction to remove the catalyst, concentrated under reduced pressure, column chromatography purification to obtain 5, 6, 7, 8 – tetrahydro imidazo [1,2 – the a] pyrazine -3 – carboxylic acid ethyl ester (600 mg, yield: 75.3%, white solid).

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

Reference:
Patent; Sichuan Kelun Pharmaceutical Institute Co., Ltd.; Xie Yinong; You Zejin; Song Zhanbo; Su Ruifei; Deng Zhiwen; Wang Yajun; Chen Xing; Zeng Hong; Song Hongmei; Qi Wei; Wang Lichun; Wang Jingyi; (57 pag.)CN106478631; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 109838-85-9, 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 109838-85-9 as follows.

Preparation 34: ((lS,2RV3-amino-l-(3,5-difluorotenzyl)-2-hydroxy-propyl)carbamic acid t-butyl esterStepA: (2S,5R)-2-(3,5-difluorobenzyl)-5-isopropyl-3,6-dimethoxy-2,5-dihvdropyrazine(R)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine was dissolved THF and n-BuLi was added thereto at -78 °C, followed by addition of difluorobenzyl chloride. After the reaction was complete, NH4Cl was added to the reaction mixture, followed by extraction with EtOAc. The organic extract was dried over MgSO4 and concentrated under reduced pressure. The residue was purified by column chromatography (eluent: EtOAc: n-Hex = 1/1) to afford the title compound (339 mg, 80percent).MSbetaVI+l] = 313 (M+l)

According to the analysis of related databases, 109838-85-9, the application of this compound in the production field has become more and more popular.

Reference:
Patent; LG LIFE SCIENCES, LTD.; WO2009/38412; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

15707-23-0, 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 15707-23-0 as follows.

Ag2O (23.2 mg, 0.1 mmol), 3-nitro-1,2-benzenedicarboxylicacid (H2npt) (42.2 mg, 0.2 mmol) and epyz (24.4 mg, 0.2 mmol) were dissolved in methanol-H2O-DMF mixed solvent (6 mL,v/v/v = 1/1/1) in the presence of ammonia (0.5 mL, 14 M) underultrasonic treatment (160 W, 40 kHz, 30 min) under 40 C. Theresultant colorless solution was allowed slowly to evaporate atroom temperature in the dark. After several days, colorless platecrystals of 1 were isolated in about a 43% yield. They were washedwith a small volume of cold ethanol. Anal. Calc. for Ag2C15H13N3O6:C, 32.94; H, 2.40; N, 7.68. Found: C, 32.98; H, 2.38; N, 7.72%. IR(KBr): m (cm1) = 3440 (m), 3088 (w),3046 (w), 2976 (m),2932(w), 2876 (w), 1590 (s), 1520 (s), 1457(s), 1408 (s), 1344 (s),1288 (m), 1162 (m), 1027 (w), 929 (m), 859 (m), 824 (m), 782(w), 747 (w), 704 (m), 683 (m), 586 (w).

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

Reference:
Article; Zhang, Ting; Wang, Dan-Feng; Huang, Rong-Bin; Zheng, Lan-Sun; Inorganica Chimica Acta; vol. 427; (2015); p. 299 – 304;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 1049026-49-4, name is 2-Bromo-5-(methylthio)pyrazine, 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 1049026-49-4, Quality Control of 2-Bromo-5-(methylthio)pyrazine

(107d) 2-Bromo-5-(methylsulfonyl)pyrazine 2,5-Dibromopyrazine (270 mg, 1.14 mmol) was dissolved in tetrahydrofuran (10 mL), and sodium thiomethoxide (320 mg, 4.57 mmol) was added at room temperature, followed by stirring at room temperature for 2.5 hours under nitrogen atmosphere. To this reaction solution, water (10 mL) was added, and extraction was carried out with diethyl ether (10 mL). The organic layer was washed with saturated brine, and subsequently dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the resulting residue was purified using silica gel column chromatography (elution solvent: ethyl acetate/hexane=5%-10%) to afford a yellow solid. This was dissolved in methylene chloride (10 mL), and m-chloroperbenzoic acid (approximately 65%, 580 mg, approximately 2.2 mmol) was added at room temperature, followed by stirring at room temperature for 1 hour under nitrogen atmosphere. To this reaction solution, a saturated aqueous sodium hydrogencarbonate solution (10 mL) was added, and extraction was carried out with methylene chloride (10 mL). The organic layer was washed with saturated brine, and subsequently dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the resulting residue was purified using silica gel column chromatography (elution solvent: ethyl acetate/hexane=15%-25%) to afford the desired compound (190 mg, yield 70%) as a white solid. 1H-NMR (CDCl3, 400 MHz): delta 3.26 (3H, s), 8.80 (1H, d, J=1.2 Hz), 9.06 (1H, d, J=1.2 Hz).

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-Bromo-5-(methylthio)pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Daiichi Sankyo Company, Limited; EP2239253; (2010); 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. 117719-17-2, name is 5-Bromo-3-morpholinopyrazin-2-amine, A new synthetic method of this compound is introduced below., Recommanded Product: 5-Bromo-3-morpholinopyrazin-2-amine

5-bromo-3-morpholin-4-yl-pyrazin-2-ylamine (300 mg, 1 eq) was suspended in EtOH (3 mL) and 2,3-dibromo-n-methylmaleimide (31 1 mg, 1 eq) was added. The reaction mixture was heated under microwave irradiation at 120 C for 4 h. On cooling, the mixture was filtered to give a yellow solid (50 mg,) which was heated at 150 C for 5 min under open air. On cooling, the mixture was purified by automated chromatography (Biotage, eluent: 2% to 10% MeOH in DCM) to obtain the expected product I-20 (22 mg) as a yellow solid.

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; CENTRO NACIONAL DE INVESTIGACIONES ONC&Oacgr;LOGICAS (CNIO); PASTOR FERNANDEZ, Joaquin; MARTINEZ GONZALEZ, Sonia; ALVAREZ ESCOBAR, Rosa Maria; RODRIGUEZ ARISTEGUI, Sonsoles; GONZALES CANTALAPIEDRA, Esther; HERNANDEZ HIGUERAS, Ana Isabel; VARELA BUSTO, Carmen; WO2011/36461; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 1458-18-0,Some common heterocyclic compound, 1458-18-0, name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, molecular formula is C6H5Cl2N3O2, 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 a stirred solution of methyl 3-amino-5, 6-dichloropyrazine-2-carboxylate (500 mg, 2.25 mol, 1 equiv) and 2- (tributylstannyl) -1, 3-oxazole (806.5 mg, 2.25 mol, 1.00 equiv) in 1, 4-dioxane (20 mL) were added LiCl (190.9 mg, 4.50 nMol, 2 equiv) , tricyclohexylphosphane (126.3 mg, 0.45 nMol, 0.2 equiv) and Pd 2 (dba) 3. CHCl 3 (466.2 mg, 0.45 nMol, 0.20 equiv) in portions at room temperature under nitrogen atmosphere. The resulted mixture was stirred for 4h at 140 under nitrogen atmosphere with microwave irritation. The resulted mixture was concentrated under reduced pressure. The residue was purified by Prep-TLC (CH 2Cl 2 /MeOH 20: 1) to afford methyl 3-amino-6-chloro-5- (1, 3-oxazol-2-yl) pyrazine-2-carboxylate (160 mg, 27.9%) as a yellow solid. LCMS: m/z (ESI) , [M+H] + = 255.1.

The synthetic route of 1458-18-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; DIZAL (JIANGSU) PHARMACEUTICAL CO., LTD.; QI, Changhe; TSUI, Honchung; ZENG, Qingbei; YANG, Zhenfan; ZHANG, Xiaolin; (399 pag.)WO2020/35052; (2020); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 54013-07-9, 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. 54013-07-9, name is 5-Methoxypyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows.

General procedure: Isoquinolin-3-amine (3.23 g, 22.4 mmol) was added to a solution of 1,1′-thiocarbonyldipyridin-2(1H)-one (5.20 g, 22.4 mmol) in dichloromethane (50 mL) at room temperature. The reaction was stirred for 2 h, then purified by flash chromatography on silica gel (0-10% ethyl acetate in hexanes). Product fractions were combined and concentrated in vacuo to give 3-isothiocyanatoisoquinoline(3.9 g, 93 %) as a white solid.

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

Reference:
Article; Iwuagwu, Christiana; King, Dalton; McDonald, Ivar M.; Cook, James; Zusi, F. Christopher; Hill, Matthew D.; Mate, Robert A.; Fang, Haiquan; Knox, Ronald; Gallagher, Lizbeth; Post-Munson Amy Easton, Debra; Miller, Regina; Benitex, Yulia; Siuciak, Judy; Lodge, Nicholas; Zaczek, Robert; Morgan, Daniel; Bristow, Linda; Macor, John E.; Olson, Richard E.; Bioorganic and Medicinal Chemistry Letters; vol. 27; 5; (2017); p. 1261 – 1266;,
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. 89283-32-9, name is (3-Chloropyrazin-2-yl)methanol, A new synthetic method of this compound is introduced below., Recommanded Product: 89283-32-9

1.44 g of 3-chloro-2-pyrazine methanol, 2 mol% of vanadium nitrate (relative to the substrate 3-chloro-2-pyrazine methanol),Add to the 50mL reaction tube, Add 5mL of acetonitrile,Fill the air ball, close the reaction tube, and raise the temperature to 40 C with stirring.And kept for 10 h, until the reaction is over, and cooled to room temperature.Sampling was analyzed using gas chromatography.The conversion rate of 3-chloro-2-pyrazine methanol is 96.1%.The selectivity of 3-chloro-2-pyrazinecarboxaldehyde is greater than 99%.

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; Dalian University of Technology; Du Zhongtian; Tang Yangyang; Sun Xiaowan; Yue Jiajia; (6 pag.)CN106866508; (2019); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem