Month: March 2021

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 14508-49-7 as follows. COA of Formula: C4H3ClN2

An oven dried resealable Schlenk tube was charged with 2′-(4-methylpiperazin-1-yl)-2,4′-bipyridin-6-amine (example 34a, 0.09 g, 0.33 mmol), 2-Chloropyrazine (0.04 muL, 0.39 mmol), sodium tert-butoxide (0.04 g, 0.38 mmol) and dioxane (1 mL). The Schlenk tube was subjected to three cycles of evacuation-backfilling with argon, and tris(dibenzylideneacetone)dipalladium(0) (0.01 g, catalytic amount) and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (0.01 g, catalytic amount) were added. After three further cycles of evacuation-backfilling with argon, the Schlenk tube was capped and placed in an oil bath at 95 C. After 16h, the mixture was cooled and the solvent was removed in vacuo. The residue was purified by flash chromatography to give the title compound (0.09 g, 82%) as a solid.LRMS (m/z): 348 (M+1)+.1 H NMR (500 MHz, CHLOROFORM-d) delta ppm 2.35 (s, 3 H) 2.53 – 2.55 (m, 4 H) 3.63 – 3.66 (m, 4 H) 7.16 (dd, J=6.50, 2 Hz, 1 H) 7.34 (s, 1 H) 7.39 (d, J=9.00 Hz, 1 H) 7.61 (d, J=10.00 Hz, 1 H) 7.73 (t, J=10.00 Hz, 1 H) 7.96 (br. s., 1 H) 8.13 (d, J=3.50 Hz, 1 H) 8.19 – 8.21 (m, 1 H) 8.13 (d, J=3.50 Hz, 1 H) 8.98 (d, J=2.00 Hz, 1 H)

According to the analysis of related databases, 14508-49-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Almirall, S.A.; Vidal Juan, Bernat; Forns Berenguel, Maria Pilar; Castillo Mcquade, Marcos; Erra Sola, Montserrat; Mir Cepeda, Marta; EP2441755; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 1053656-22-6, The chemical industry reduces the impact on the environment during synthesis 1053656-22-6, name is 7-tert-Butyl 2-ethyl 5,6-dihydroimidazo[1,2-a]pyrazine-2,7(8H)-dicarboxylate, I believe this compound will play a more active role in future production and life.

Stage 2: A solution of 7-tert-butyl 2-ethyl 5,6-dihydroimidazo[1,2-a]pyrazine-2,7(8H)-dicarboxylate (300 mg, 1.02 mmol) in THF (15 ml) was cooled to -78 C., and DIBAL-H (1 M in hexane, 2.0 ml, 2.0 mmol) was added slowly under an N2 atmosphere. The reaction mixture was stirred for 1 hour at that temperature and then Na2SO4¡Á10H2O was added until no further evolution of gas was observed. Further sodium sulfate was added, the solution was filtered, and the residue was washed with DCM (25 ml). The filtrate was concentrated and the resulting crude product (450 mg) was used in the next stage without further purification.

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, 7-tert-Butyl 2-ethyl 5,6-dihydroimidazo[1,2-a]pyrazine-2,7(8H)-dicarboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GRUENENTHAL GmbH; US2010/173889; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 33332-28-4, name is 2-Amino-6-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 33332-28-4, COA of Formula: C4H4ClN3

EXAMPLE 11 N-(6-Chloro-pyrazin-2-yl)-4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide This compound was prepared from ethyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide and 2-amino-6-chloro-pyrazine analogous to Example 1. Yield: 60percent of theory. Melting point: 278-279¡ã C. (decomposition). C14 H11 ClN4 O4 S (366.79): Calc.: C–45.84percent; H–3.03percent; Cl–9.67percent; N–15.28percent; S–8.74percent. Found: C–45.91percent; H–3.09percent; Cl–9.60percent; N–15.00percent; S–8.78percent.

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-Amino-6-chloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Dr. Karl Thomae Gesellschaft mit beschrankter Haftung; US4533664; (1985); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference 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: 2-Cyanopyridine (0.420 ml; 4 mmol) was dissolved in absolute methanol (20 ml) and to it was added sodium methoxide solution in methanol (1.0 ml) (previously prepared). The reaction contents were stirred at room temperature for 2 h 1,4-diaminobutane (0.18 ml, 2 mmol) was added to the reaction mixture. Reaction contents were heated under reflux for 12 h. Solvent was removed under reduced pressure. Crude product so obtained was washed with diethyl ether and then with ethyl acetate to give thick mass. Solvent traces from this thick mass was removed by applying high vacuum for 15 min to give semisolid product i.e. N-(2-pyridineimidoylamino-butyl)-pyridine-2-carboxamidine (5a). Yield 480 mg (81%).

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

Reference:
Article; Arya, Surbhi; Kumar, Nikhil; Roy, Partha; Sondhi; European Journal of Medicinal Chemistry; vol. 59; (2013); p. 7 – 14;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 95-89-6, These common heterocyclic compound, 95-89-6, name is 3-Chloro-2,5-dimethylpyrazine, 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.

a. 3,6-Dimethylpyrazin-2-amine A 100 mL autoclave vessel was charged with 3-chloro-2,5-dimethylpyrazine (25.0 g, 176 mmol), NH3 (aq. 25-28% w/w, 80 mL) and Cu powder (1.69 g, 26.4 mmol) and the autoclave vessel was sealed. The resulting mixture was heated to 150 C. and stirred vigorously for 48 h. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The residue was diluted with brine (100 mL) and extracted with EtOAc (4*100 mL). The combined extracts were dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was washed with PE to render the title compound as a light yellow solid (17.6 g, yield 81%). ESI MS: m/z 124 [M+H]+.

The synthetic route of 95-89-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Sunovion Pharmaceuticals Inc.; US2012/178748; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 16298-03-6, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 16298-03-6 name is Methyl 2-aminopyrazine-3-carboxylate, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

(A) Methyl 2-bromo-3-pyrazine carboxylate: To a stirred mixture of 12.7 g. of methyl 2-amino pyrazine carboxylate and 47 ml. of 48percent hydrobromic acid there was added, dropwise, 12.6 ml. of bromine keeping the temperature at 0¡ã. A solution of 14.4 g. of sodium nitrite in 60 ml. of water was then added, dropwise, at 0¡ã and the reaction mixture stirred for 15 minutes. The reaction mixture was basified to pH 8 with sodium bicarbonate and extracted with ethyl acetate and again with chloroform. The organic layers were dried over magnesium sulfate, filtered and concentrated to a yellow oil. Recrystallization from ether-hexane yielded the product, m.p. 43¡ã-45¡ã C.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Methyl 2-aminopyrazine-3-carboxylate, and friends who are interested can also refer to it.

Reference:
Patent; Schering Corporation; US4680297; (1987); A;; ; Patent; Schering Corporation; US4680298; (1987); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 1458-01-1,Some common heterocyclic compound, 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, molecular formula is C6H7ClN4O2, 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.

Preparation Example AA-1. 3,5-Diamino-pyrazine-2-carboxylic acid methyl ester To a solution of 3,5-diamino-6-chloro-pyrazine-2-carboxylic acid methyl ester (8.00g, 39.5mmol) in tetrahydrofuran (150mL) were added tetrakis(triphenylphosphine)palladium(0) (2.28g, 1.98mmol), formic acid (2.24mL, 59.3mmol) and triethylamine (16.5mL, 119mmol) at 0¡ãC under nitrogen atmosphere, then, the solution was stirred at 125¡ãC for 12 hours. The reaction solution was cooled to room temperature, and a solid precipitated. This solid was collected by filtration, and the title compound (10.7g, quantitatively) was obtained as a crude product of a white solid. 1H-NMR Spectrum (DMSO-d6) delta (ppm) : 3.70(3H, s), 6.95(2H, brs), 7.21 (1H, s).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, its application will become more common.

Reference:
Patent; Eisai R&D Management Co., Ltd.; EP1782811; (2007); 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. 912773-21-8, name is 2-Bromo-5-chloropyrazine, A new synthetic method of this compound is introduced below., Application In Synthesis of 2-Bromo-5-chloropyrazine

A mixture of Pd(dppf)Cl2 (15.13 g, 20.68 mmol), CS2CO3 (269.49 g, 827.17 mmol), 3-fluoro-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)-2-(2,2,2- trifluoroethoxy)pyridine (141.18 g, 439.69 mmol) and 2-bromo-5-chloro-pyrazine (80 g, 413.59 mmol) in l,4-Dioxane (1 L) and Water (150 mL) under N2 was stirred at 35 C for 2 hours. After cooling to room temperature, to the mixture was added water (300 mL) and the mixture was filtered through Celite. After separating, the organic phase was washed with brine (300 mL), dried over anhydrous Na2S04, filtered and concentrated to give the crude product. The crude product was re-dissolved in EA/PE = 1/3 (500 mL) and then filtered through silica gel mat. The cake was washed with EA/PE = 1/3 (500 mL). The combined organic phase was concentrated to give a residue as oil. To the oil was added PE (500 mL) slowly and some solid was obtained. The solid was collected and dried in oven to give the product (100 g, 242.4 mmol, 58% yield) as a solid. LCMS Rt= 1.28 min in 2.0 min chromatography, 10-80AB, MS ESI calcd. for C11H7CIF4N3O [M+H]+308.0, found 307.9.

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; PRAXIS PRECISION MEDICINES, INC.; GRIFFIN, Andrew, Mark; MARRON, Brian, Edward; MARTINEZ BOTELLA, Gabriel; REDDY, Kiran; WITTMANN, Marion; (0 pag.)WO2019/232209; (2019); 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. 4949-13-7, name is 2-Fluoropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Formula: C4H3FN2

To a stirred solution of 2-fluoropyrazine (1 g, 10.20 mniol) in DMO (12 mL) was added 3-brorno-4-fluorophenoi (1.95 g, 10.21 mmoi), and K2C03 (2.82 g, 20.39 mmol), The reactionmixture was stirred at 75C for 15 h. The mixture was filtered, and the filtrate was diluted with brine (50 mL). The filtrate was extracted with EIOAc (2×100 mE), The organic layer was dried over NaO4, filtered and concentrated in vacuo to give the title compound. m/z 270.9(M¡À2+H).

According to the analysis of related databases, 4949-13-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MERCK SHARP & DOHME CORP.; ADAMS, Gregory, L.; COX, Jason, M.; DEBENHAM, John, S.; EDMONDSON, Scott; GILBERT, Eric, J.; GUO, Yan; JIANG, Yu; JOSIEN, Hubert; KIM, Hyunjin, M.; LAN, Ping; MIAO, Shouwu; PLUMMER, Christopher, W.; RAJAGOPALAN, Murali; SHAH, Unmesh; SUN, Zhongxiang; TRUONG, Quang, T.; UJJAINWALLA, Feroze; VELAZQUEZ, Francisco; VENKATRAMAN, Srikanth; SUZUKI, Takao; WANG, Nengxue; (182 pag.)WO2017/205193; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 6164-79-0, These common heterocyclic compound, 6164-79-0, name is Methyl 2-pyrazinecarboxylate, 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.

Pyrazine-2-carboxylic acid hydrazide. To a stirred solution of pyrazine-2-carboxylic acid methyl ester (11.1 g, 80 mmol) in 140 mL OF ETOH was added hydrazine hydrate (15.6 ML, 320 mmol). The resultant solution was heated to reflux for 2h. The solvent was removed under reduced pressure and dried under high vacuum to yield the title amide (11.1 g, 100%) as a white solid. The product was used in subsequent steps without purification.

Statistics shows that Methyl 2-pyrazinecarboxylate is playing an increasingly important role. we look forward to future research findings about 6164-79-0.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2005/16909; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem