Author: Jessica.F

These common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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. Application In Synthesis of 2-Amino-3,5-dibromopyrazine

Morpholine (50 mL) was added to a three-necked flask containing 12.50 g of 3,5-dibromo-2-aminopyrazine and maintained at 80 CThe reaction was completed by the reaction of TLC for 1 h. The refluxed system was cooled to room temperature and added to a mixture containing ice water (300 mL)The mixture was stirred and dried to give 12.30 g of a yellow solid with metallic luster, i.e., 3-morpholine-5-Bromo-2-aminopyrazine in a yield of 96.1%.

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

Reference:
Patent; Jiangxi Science and Technology Normal University; Zhu Wufu; Zheng Pengwu; Sun Chengyu; Chen Chen; Xu Shan; Tang Qidong; Wang Wenhui; Wang Qinqin; Wang Caolin; (23 pag.)CN106831812; (2017); A;,
Pyrazine – Wikipedia,
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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. 54608-52-5, name is 2-Hydrazinopyrazine, This compound has unique chemical properties. The synthetic route is as follows., SDS of cas: 54608-52-5

A mixture of 2-hydrazinopyrazine (820 mg, 7.45 mmol), prepared from 2- chloropyrazine and hydrazine using a procedure analogous to that described in the literature (P. J. Nelson and K. T. Potts, J. Org. Chem. 1962, 27, 3243, except that the crude product was extracted into 10% methanol/dichloromethane and filtered, and the filtrate was concentrated and purified by flash chromatography on silica gel, eluting with 100% ethyl acetate followed by 10% methanol in dichloromethane), TFA (2.55 g, 22.4 mmol), and polyphosphoric acid (10 mL) was heated to 140 C with stirring for 18 h. The solution was added to ice and neutralized by the addition of ammonium hydroxide. The aqueous solution was extracted with ethyl acetate (3X), washed with brine, and dried over anhydrous magnesium sulfate. Concentration followed by flash chromatography (silica gel, 1: 1 hexane: ethyl acetate, then 100% ethyl acetate) afforded the title compound as a SOLID. 1H NMR (500 MHz, CDC13) 8 8. 17-8. 20 (m, 2H), 9.54 (s, 1H). LC/MS (M+1) 189.

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 54608-52-5.

Reference:
Patent; MERCK & CO., INC.; WO2004/58266; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 14508-49-7, 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. 14508-49-7, name is 2-Chloropyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

A mixture of 2-chloropyrazine (4.00 g) andhydrazine hydrate was heated at 1 10 C for 1 h, and then cooled to room temperature. The mixture was filtered to give the title compound as a solid (2.30 g, 60.00 %). The compound was characterized by the following spectroscopic data: MS (ESI, pos. ion) m/z: 1 1 1.0 (M+ l).

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-Chloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; SUNSHINE LAKE PHARMA CO., LTD.; ZHANG, Jiancun; ZHANG, Yingjun; ZHANG, Weihong; LIU, Bing; ZHANG, Jiquan; LIU, Jinlei; ZHANG, Lu; WO2013/71697; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4744-50-7,Some common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, molecular formula is C6H2N2O3, 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: A solution of 3,4,5-trichloroaniline (1.96 g, 10 mmol) and acid anhydride (10 mmol) in glacial acetic acid (20 mL) was refluxed for 3 h. The solvent was removed under reduced pressure until the volume reached ca. 5 mL. After addition of 10 mL of acetic anhydride, the solution was refluxed again for 20 h. The solvent was removed under reduced pressure. The residue was neutralized by a solution of sodium bicarbonate (4%) until effervescence ceased. The precipitate obtained was washed with water, dried (P2O5) and recrystallized from an appropriate solvent.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2,3-Pyrazinecarboxylic anhydride, its application will become more common.

Reference:
Article; Abdel-Aziz, Alaa A.-M.; Eltahir, Kamal E.H.; Asiri, Yousif A.; European Journal of Medicinal Chemistry; vol. 46; 5; (2011); p. 1648 – 1655;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 69214-33-1, name is 8-Chloroimidazo[1,2-a]pyrazine, 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. Quality Control of 8-Chloroimidazo[1,2-a]pyrazine

A vial containing tert-butyl 2,8-diazaspiro[4.5]decane-8-carboxylate (263 mg, 1.09 mmol), 8- chloroimidazo[l,2-a]pyrazine (168 mg, 1.09 mmol) and triethyl amine (152 uL, 1.09 mmol) in THF (5.4 mL) heated to 50C for 4 hours. The reaction was cooled and concentrated to give the crude material, which was purified via MPLC (50-100% EtOAc/hexanes) to afford the title compound. LC-MS (357, m/z): 358 [M+l]+.

The synthetic route of 8-Chloroimidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; PASTERNAK, Alexander; PIO, Barbara; CHOBANIAN, Harry, R.; SHI, Zhi-Cai; DONG, Shuzhi; GUO, Yan; WALSH, Shawn, P.; GUO, Zhiqiang; FERGUSON, Ronald, D.; CATO, Brian; (114 pag.)WO2016/60941; (2016); 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. 41110-33-2, name is Methyl 5-methylpyrazine-2-carboxylate belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below. COA of Formula: C7H8N2O2

[0115j To a solution of methyl 5-methylpyrazine-2-carboxylate (0.5 g, 3.28 mmol) in acetic acid (5 ml) was added bromine (0.i9 ml, 3.6i mmol) at room temperature. The reaction mixture was heated at 80C for 45 mm. The reaction mixture was concentrated to remove acetic acid. The residue was basified with saturated sodium bicarbonate solution and extracted with ethyl acetate. The organic layer was dried and concentrated. The crude was purified by silica gel column chromatography using 20% ethyl acetate in hexane to afford the title compound methyl 5-(bromomethyl)pyrazine-2-carboxylate (0.3 g, 40%) as a brownish liquid. Calculated M+H: 230.97; Found M+H: 231.0.

The synthetic route of 41110-33-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MNEMOSYNE PHARMACEUTICALS, INC.; ANDERSON, David R.; VOLKMANN, Robert A.; WO2015/48503; (2015); A2;,
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. 21279-64-1, name is 5-Chloropyrazine-2-carboxamide belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 21279-64-1

5.3. 2-[[3-[4-(5-Chloro-2-methoxyphenyl)piperazin-1-yl]propyl]amino]pyrazine-5-carboxamide (E)-but-2-enedioate (1:1) 13.67 g (0.04817 mol) of 3-[4-(5-chloro-2-methoxyphenyl)piperazin-1-yl]propanamine, 8.65 g (0.062 mol) of potassium carbonate and 7.59 g (0.04817 mol) of 2-chloropyrazine-5-carboxamide in suspension in 200 ml of dimethylformamide are introduced into a 500 ml round-bottomed flask and the mixture is stirred at room temperature for 48 h. The solvent is evaporated under reduced pressure, the residue is purified by recrystallization from ethyl acetate and 12.6 g of base are obtained. The fumarate is prepared from 1.58 g (0.0039 mol) of base in 50 ml of ethanol and from 0.47 g (0.0039 mol) of fumaric acid in 50 ml of ethanol. The mixture is concentrated and the product recrystallized from a methanol/ethanol mixture. 1.08 g (0.00207 mol) of white solid are finally obtained. Melting point=219-223 C. (decomposition).

The synthetic route of 21279-64-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Synthelabo; US5420130; (1995); A;,
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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of Methyl 2-aminopyrazine-3-carboxylate

Example 3a Methyl 3-amino-6-iodopyrazine-2-carboxylate 1.5 equivalents of N-iodosuccinimide are added at room temperature to 5 g (32.7 mmol) of a methyl 3-aminopyrazine-2-carboxylate solution in 25 ml of dimethylformamide The reaction medium is heated at 65¡ã C. for 1 hour, added together with 0.5 equivalents of N-iodosuccinimide and maintained at 65¡ã C. for 24 hours. After returning to room temperature, the solvent is evaporated and then the product is extracted several times with dichloromethane. The organic phases are combined, washed with 10percent sodium bisulfite solution, dried on magnesium sulfate and concentrated to yield 8 g (88percent) of methyl 3-amino-6-iodopyrazine-2-carboxylate in the form of a yellow solid. LCMS (EI, m/z): (M+1) 280 1H NMR: deltaH ppm (400 MHz, DMSO): 8.50 (1H, s, CHarom), 7.50 (2H, bs, NH2), 3.20 (3H, s, CH3).

According to the analysis of related databases, 16298-03-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PIERRE FABRE MEDICAMENT; KALOUN, El Bachir; BEDJEGUELAL, Karim; RABOT, Remi; KRUCZYNSKI, Anna; SCHMITT, Philippe; PEREZ, Michel; RAHIER, Nicolas; US2013/85144; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 76537-18-3, A common heterocyclic compound, 76537-18-3, name is 3-Bromo-5-chloropyrazin-2-amine, molecular formula is C4H3BrClN3, 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.

The suspension of 18a (3 g, 14.5 mmol), NaCN (0.85 g, 17.4 mmol), CuI (1.3 g, 7.3 mmol) and Pd(PPh3)4 (0.17 g, 0.15 mmol) were stirred in DMF (40 mL) at 120 C for 10 h under nitrogen protection. After cooling to room temperature, 10% aqueous solution of Na2S2O3(10 mL), water (60 mL) and ethyl acetate (200 mL) were added. The resulting mixture was stirred for 10 min, then filtered, and the filter cake was washed with ethyl acetate (150 mL). The organic layer was separated, washed with water (3 ¡Á 50 mL),dried over anhydrous Na2SO4and concentrated. The residue was purified by chromatography on silica gel eluting with PE/EA (10:1-2:1) to give a light-yellow solid (1.9 g, yield 85%). 6-Chloro-3-aminopyrazine-2-carbonitrile (19a) Yield: 85%, light-yellow solid, M.p.: 156-158 C. 1H NMR(400 MHz, CDCl3):delta 8.23 (s, 1H), 5.34 (s, 2H). 13C NMR(100 MHz, CDCl3):delta 154.98, 146.84, 137.41, 114.07,111.16. EI-MS m/z: 154 (M+, Cl35,100), 156 (M+, Cl37,35),127 (M+, Cl35,-H, -CN, 48), 129 (M+, Cl37,-H, -CN, 15).

The synthetic route of 76537-18-3 has been constantly updated, and we look forward to future research findings.

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

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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Recommanded Product: Methyl 5-chloropyrazine-2-carboxylate

Preparation of 5-Chloropyrazine-2-carboxylic acid To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added methyl 5-chloropyrazine-2-carboxylate (1.0 eq) and tetrahydrofuran (4.92 vols) under a nitrogen atmosphere. The reaction mixture was agitated until all the solid had dissolved, then filtered into a second flask. Water (8.65 vols) was added to the reaction mixture and the mixture agitated for approximately 15 minutes. Potassium carbonate (2.1 eq) was added to the reaction mixture and the mixture agitated for 16 hours at 20-25 C. Then 32% w/w hydrochloric acid (3.76 eq) was added over 3 hours in small portions, keeping the reaction temperature 20-25 C., to a pH end point of pH2.2. The resultant slurry was heated to approximately 35-40 C. and then distilled under vacuum at this temperature distilling approximately 5.3 vols, to a final volume of approximately 9.3 vols. The mixture was then cooled to 20-25 C. over at least 2 hours, agitated for 10 hours at this temperature and then filtered. The solid was washed with water (2.8 vols), and the wet product produced dried at 35 C. in a vacuum oven. The desired product was obtained as a solid (corrected yield 91%) 1H NMR delta (400 MHz CDCl3): 7.20 (1H, bs), 8.72 (1H, s), 9.21-9.21 (1H, m); m/z 157 (M-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; AstraZeneca AB; US2010/210621; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem