Month: July 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 (1.48 g, 0.01 mol),and Ethynyl-benzene (1.53 g, 0.015 mol) was added in a lOOmL flask which contained 30mL of Et3N with stirring, and then the catalyst of Cul(0.38 g, 0.002 mol)and Pd(PPh3) 2C12(2 g, 0.002 mol) was added into the mixture. The reaction mixture was warmed to 80C for 0.5h, lc-ms indicated 2,3-Dichloro-pyrazine was consumed. The reaction mixture was cooled to room temperature. Filtrated, the filtrate was concentrated to give the crude product, the crude product was further purified by flash chromatography to afford 2-Chloro-3-phenylethynyl-pyrazine. (1.5 g, yield: 71%). LC/MS (ESI+): 215 [M+l]+ 217 [ +3]+

The synthetic route of 4858-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ARRAY BIOPHARMA INC.; GENENTECH, INC.; SKELTON, Nicholas; GRADL, Stefan; BLAKE, James F.; GRAHAM, James M.; GUNAWARDANA, Indrani W.; HENTEMANN, Martin; MARLOW, Allison L.; TANG, Tony P.; WO2013/78254; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 622392-04-5, 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. 622392-04-5, name is 2-Bromo-5-iodopyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Tert-butyl 4-{[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridin-1-(2H)-yl]sulfonyl}tetrahydro-2H-pyran-4-carboxylate (10 g, 21.86 mmol, Gateway Chemical), 2-bromo-5-iodopyrazine (6.23 g, 21.86 mmol, Gateway Chemical), toluene (105 mL), ethanol (32 mL), 2M Na2CO3(aq) (64 mL), and [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with CH2Cl2 (1:1) (0.892 g, 1.1 mmol, Aldrich) were heated together under N2 at 73 C. for 3 hr and then cooled to ambient temperature overnight. The resulting mixture was diluted with ethyl acetate (300 mL) and deionized water (200 mL). The layers were separated, and the aqueous was back-extracted with ethyl acetate (100 mL). The combined ethyl acetate layers were washed with 150 mL each of sat. NaHCO3(aq) and brine, dried over MgSO4, filtered, and concentrated to afford an oil in vacuo. The oil was purified by chromatography on silica (heaxnes/ethyl acetate) to afford 7.68 g (72% yield) of solids.

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

Reference:
Patent; Barta, Thomas E.; Becker, Daniel P.; Bedell, Louis J.; Boehm, Terri L.; Brown, David L.; Carroll, Jeffery N.; Chen, Yiyuan; Fobian, Yvette M.; Freskos, John N.; Gasiecki, Alan F.; Grapperhaus, Margaret L.; Heintz, Robert M.; Hockerman, Susan L.; Kassab, Darren J.; Khanna, Ish K.; Kolodziej, Stephen A.; Massa, Mark A.; McDonald, Joseph J.; Mischke, Brent V.; Mischke, Deborah A.; Mullins, Patrick B.; Nagy, Mark A.; Norton, Monica B.; Rico, Joseph G.; Schmidt, Michelle A.; Stehle, Nathan W.; Talley, John J.; Vernier, William F.; Villamil, Clara I.; Wang, Lijuan J.; Wynn, Thomas A.; US2005/9838; (2005); 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. 1458-03-3, name is Methyl 3-amino-6-chloropyrazine-2-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C6H6ClN3O2

(b) Methyl 2-amino-5-chloropyrazine-3-carboxylate (3.75 g) was added to a solution of sodium hydroxide (2.0 g) in water (20 ml) and the solution was heated under reflux for 1.5 hours. The reaction mixture was cooled to 0 C. and the precipitate which had formed was collected by filtration. The solid was redissolved in water (60 ml) with heating and the solution was filtered. The filtrate was then acidified to pH 2 with 2M hydrochloric acid. The precipitate which formed was collected by filtration and washed with ice/water (2*20 ml) and dried under vacuum. The solid was suspended in diphenyl ether (15 ml) and heated at reflux under an argon atmosphere for 15 minutes. The reaction mixture was cooled to ambient temperature and diluted with hexane (15 ml). The precipitate which formed was collected by filtration and washed with hexane (3*25 ml) to give 2-amino-5-chloropyrazine (1.78 g); 1 H NMR (d6 -DMSO): 6.55 (br s, 2 H), 7.67 (d, 1 H), 7.95 (d, 1 H); mass spectrum (+ve CI): 130 (M+H)+.

According to the analysis of related databases, 1458-03-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Zeneca Limited; US5866568; (1999); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-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. Computed Properties of C6H6BrN3O2

Methyl beta-bromo-S-chloropyrazine-l-carboxylate (1-2)To a suspension of copper (II) chloride (3.48 g, 25.9 mmol, 2.0 equiv) in acetonitrile (43 mL) was added te/t-butylnitrite (3.06 mL, 25.9 mmol, 2.0 equiv). The reaction was heated to 600C for 30 minutes and then cooled to ambient temperature. To this suspension was added methyl 3-amino-6-bromopyrazine-2-carboxylate (Ll, 3.O g, 12.9 mmol, 1.0 equiv, commercially available from SynChem Inc.) as a solid in portions with gas evolution. The reaction mixture was heated to reflux for 18 hours and the reaction was cooled to ambient temperature. The reaction was partitioned between EtOAc and saturated NaHCO3. The organic phase was washed with NaHCO3 and dried over MgSO4. After concentration, the residue was purified by normal phase column chromatography (0 to 50% EtOAc in hexanes) to afford the product CL2) as a clear oil. ESI+ MS [M+H]+ C6H4BrClN2O2: 250.7 found, 250.9 required.

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

Reference:
Patent; MERCK SHARP &; DOHME CORP.; MERCER, Swati, P.; ROECKER, Anthony, J.; WO2010/141275; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 4949-13-7, 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. 4949-13-7, name is 2-Fluoropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Step A: Ethyl 3(2,4-difluorophenyl)-1-(pyrazin-2-yl)-1H-thieno[2,3-c]pyrazole-5-carboxylate Ethyl 3-(2,4-difluorophenyl)-1H-thieno[2,3-c]pyrazole-5-carboxylate (82.0 mg, 0.266 mmol), 2-fluoropyrazine (134.6 mg, 1.372 mmol) and cesium carbonate (263.7 mg, 0.809 mmol) were dissolved in N,N-dimethylformamide (2.60 mL) at 25 C under Ar. The reaction mixture was heated to 80 C allowed to stir for 2 h. The reaction was stopped, cooled to room temperature, quenched by addition of saturated aqueous ammonium chloride (10 mL), and the mixture extracted with ethyl acetate (3 x 15 mL). The combined organic phases were washed with saturated aqueous ammonium chloride (2 x 10 mL) and saturated aqueous sodium chloride (1 x 10 mL), dried (sodium sulfate), filtered, and the solvent evaporated under reduced pressure. The crude product was purified by flash chromatography (RediSep SiO2, 40 g column) on a CombiFlash Rf purification system eluting with ethyl acetate-hexanes (0-50%). The title compound (55.3 mg, 0.143 mmol, 53.8 % yield) was recovered as a light yellow/white solid. LC-MS [M+1] = 387.3.

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

Reference:
Patent; Merck Sharp & Dohme Corp.; BURGEY, Christopher, S.; CROWLEY, Brendan, M.; DENG, Zhengwu, J.; PAONE, Daniel, V.; POTTEIGER, Craig, M.; (109 pag.)EP2411001; (2018); B1;,
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. 27825-21-4, name is Methyl 3-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Recommanded Product: Methyl 3-chloropyrazine-2-carboxylate

Step 2: Methyl 3-(pyridin-2-yl)pyrazine-2-carboxylate (Y2) To a solution of the product from step 1 (100 mg, 0.58 mmol) in toluene (2 mL) was added Pd(PPh3)4 (134 mg, 0.12 mmol) and 2-(tributylstannyl)pyridine (213 mg, 0.58 mmol) at room temperature and the resulting mixture was heated to 100 C overnight. After cooled to RT, the mixture was filtered and 5 mL of aq. KF solution was added to the filtrate. The resulting mixture was stirred for 30 mins and extracted with EtOAc (5 mL x 3). The combined organic layers were washed with brine, dried over Na2S04, filtered and concentrated in vacuo. The residue was purified by chromatography (30% EtOAc in petroleum ether) to provide the title compound. LRMS m/z (M+H) 216.1 found, 216.1 required.

The synthetic route of 27825-21-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; KIM, Ronald; KUDUK, Scott, D.; LIVERTON, Nigel; ZHUO, Gang; (116 pag.)WO2016/100161; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 1082843-70-6, name is 3,5-Dibromo-2-chloropyrazine, 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 1082843-70-6, Recommanded Product: 3,5-Dibromo-2-chloropyrazine

Step 1. Preparation of 6-bromo-3-chloro-N-((tetrahydro-2H-pyran-4-yl)methyl)pyrazin-2- amine.To a scintillation vial containing 3,5-dibromo-2-chloropyrazine (1 g, 3.67 mmol) and TEA (1 .024 ml, 7.34 mmol) was added MeCN (5 ml) and (tetrahydro-2H-pyran-4- yl)methanamine (0.557 g, 3.67 mmol). The homogenous reaction mixture was capped, and heated to 80 C in a oil bath for 4 hr. The reaction mixture was concentrated to dryness, diluted with EtOAc and sequentially washed with sat NaHC03, and sat NaCI. The organic layer was dried Na2S04, filtered and concentrated. The crude was purified by column chromatography on silica gel ( 20%EtOAc/Hexane) to yield 6-bromo-3-chloro- N-((tetrahydro-2H-pyran-4-yl)methyl)pyrazin-2-amine (688 mg, 2.244 mmol, 61 .1 % yield), yield), LCMS (m/z): 308.0 (MH+), retention time = 0.94 min, and 6-bromo-5- chloro-N-((tetrahydro-2H-pyran-4-yl)methyl)pyrazin-2-amine (55 mg, 0.179 mmol, 4.89 % yield), LCMS (m/z): 308.0 (MH+), retention time = 0.91 min.

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; NOVARTIS AG; ANTONIOS-MCCREA, William R.; BARSANTI, Paul A.; HU, Cheng; JIN, Xianming; MARTIN, Eric J.; PAN, Yue; LIN, Xiaodong; PFISTER, Keith B.; RENHOWE, Paul A.; SENDZIK, Martin; SUTTON, James; WAN, Lifeng; WO2012/101062; (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. 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, A new synthetic method of this compound is introduced below., Recommanded Product: 939412-86-9

The reaction mixture of 2- (5-chloro-4-fluoro-2-isopropoxy-3- (6- (trifluoromethyl) pyridin-3-yl) phenyl) propanoic acid (520 mg, 1.28 mmol) , (3-chloropyrazin-2-yl) methanamine hydrochloride (293 mg, 2.05 mmol) , Benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (998 mg, 1.92 mmol) and N, N-Diisopropylethylamine (330 mg, 2.56 mmol) in DMF (20 mL) was stirred at room temperature for overnight. After completed, the solvent was evaporated in vacuo and the residue was dissolved with ethyl acetate. The mixture was washed with water and brine, dried over Na 2SO 4, filtered and evaporated in vacuo to give the product which was used directly for the next step without further purification. MS (M+H) + 531.1.

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; BEIGENE, LTD.; LI, Jing; ZHAO, Haibo; WANG, Zhiwei; (193 pag.)WO2018/103688; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 193966-70-0, name is Methyl 5-(bromomethyl)pyrazine-2-carboxylate, molecular formula is C7H7BrN2O2, 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. Product Details of 193966-70-0

Example 112 5-{3-Chloro-4-[2-(2-chloro-pyridin-4-yl)-3,3,3-trifluoro-2-hydroxy-1-methyl-propyl]-phenoxymethyl}-pyrazine-2-carboxylic acid methyl ester The title compound was prepared in analogy to Example 101 from 3-chloro-4-[2-(2-chloro-pyridin-4-yl)-3,3,3-trifluoro-2-hydroxy-1-methyl-propyl]-phenol (obtained in Example 19, step 5) and 5-bromomethyl-pyrazine-2-carboxylic acid methyl ester [CAS Reg. No. 193966-70-0]. MS (m/e)=516.3 [MH+].

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 193966-70-0, its application will become more common.

Reference:
Patent; Hunziker, Daniel; Lerner, Christian; Mueller, Werner; Sander, Ulrike Obst; Pflieger, Philippe; Waldmeier, Pius; US2010/249139; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 762240-92-6, These common heterocyclic compound, 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, 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.

General procedure: To the stirred reaction mixture of 3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,2,4-triazolo-[4,3-a]pyrazine hydrochloride(11) (300 mg, 1.32 mmol), TEA (0.55 mL, 3.95 mmol)and toluene (10 mL), substituted cyanates 12(a-e)/isocyanates12(f-j) (1.32 mmol) were added at ambient temperature.The reaction mass was agitated at 75-80 C until thecompletion of the reaction that was monitored by TLC. Thereaction mass was allowed to cool at ambient temperatureand it was washed sequentially with 3% aqueous HCl(5.0 mL) and then water (5.0 mL). The organic fraction wasconcentrated under vacuum at 50-55 C to obtain crudeproduct. It was purified by column chromatography using10-50% of EtOAc:hexane mixture as a mobile phase. N-(4-Fluorophenyl)-3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1, 2, 4]triazolo [4,3-a]pyrazine-7-carboxamide (13a); White crystalline solid; m.r.: 206-208 C. IR (KBr, nu/cm-1):3360 (N-H, str); 1674 (C=O, str); 1544 (C=N, str); 1163(-CF3, str). 1H NMR (400 MHz; DMSO-d6), d, ppm (J, Hz):3.95-3.98 (2H, t, J5.2, Piperazine), 4.22-4.24 (2H, t,J5.2, Piperazine), 4.95 (2H, s, Piperazine), 7.08-7.13 (2H,m, Ar-H), 7.43-7.79 (2H, m, Ar-H), 8.9 (1H, s, NH). 13CNMR (100 MHz; DMSO-d6), d, ppm (J, Hz): 39.98 (-CH2-CH2-); 40.87 (-CH2-CH2-); 43.30 (CH2-C-), 114.79 (d,J22.0, CF3), 117.12 (d, J268.0, C-F Ar), 121.68 (d,J8.0, C Ar), 136.14, 151.09 (-C=O), 154.59 (C Ar), 156.50(C Ar), 158.87 (C Ar). LC-MS, m/z, (rel, %): 330.09 [M+H]+ (100). HRMS (FAB) Calc.: C13H11F4N5O:329.08997; Found: 330.0967 [M+H+].

Statistics shows that 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride is playing an increasingly important role. we look forward to future research findings about 762240-92-6.

Reference:
Article; Mannam, Madhava Rao; Devineni, Subba Rao; Pavuluri, Chandra Mouli; Chamarthi, Naga Raju; Kottapalli, Raja Sekhara P.; Phosphorus, Sulfur and Silicon and the Related Elements; vol. 194; 9; (2019); p. 922 – 932;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem