Category: Pyrazines

Adding a certain compound to certain chemical reactions, such as: 6164-79-0, name is Methyl 2-pyrazinecarboxylate, 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 6164-79-0, Recommanded Product: Methyl 2-pyrazinecarboxylate

To a 2L 3-neck round-bottomed flask under a nitrogen atmosphere was charged NaH (22.11 g, 552.77 mmol) (60% dispersion in oil). Toluene (250 mL) was charged to the flask and the resulting slurry was stirred for 15 minutes at 20 C. The slurry was allowed to settle and the toluene removed by decantation. Additional toluene (250 mL) was added and the slurry was stirred for at 20 C. Methyl propionate (53.23 mL, 552.77 mmol) suspended in anhydrous toluene (250 mL) was added dropwise over 30 minutes. The resulting slurry was then heated to reflux temperature (external oil bath a140 C.). To the refluxing suspension was charged methyl pyrazine-2-carboxylate (54.72 g, 394.83 mmol) in anhydrous toluene (300 mL) (from step 1 of the process) dropwise over a period of 45 minutes. The reaction contents were heated at reflux temperature for 2.5 hours. The resultant dark brown slurry was allowed to cool to 20 C. Saturated ammonium chloride solution (500 mL) was charged to the slurry in one portion and the biphasic solution was vigorously stirred for 120 minutes, then agitation was stopped and the phases were allowed to separate. The dark brown-coloured lower aqueous phase (approx. 500 mL) was removed and the remaining yellow/orange-coloured upper organic phase (approx. 900 mL) was retained and combined with toluene extracts (2*175 mL) of the aqueous phase. The organic phase was filtered to remove solid particulates and concentrated in vacuo a45 C. to a volume of 400 mL to yield the desired methyl-2-methyl-3-(pyrazin-2-yl)-3-oxopropionate, which was used directly in the next reaction step. A small analytical sample was concentrated in vacuo a35 C. to yield a viscous oil. Structure was confirmed by 1H NMR and 13C NMR.

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, Methyl 2-pyrazinecarboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Patrick Prendergast; US2004/53989; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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 4774-14-5

EXAMPLE 22 To a solution of diisopropylamine (0.78 g) in tetrahydrofuran (40 ml) is added dropwise a 1.6M solution of n-butyl lithium in hexane (4.82 ml) in a dry ice-acetone bath over a period of 3 minutes. The mixture is stirred in the same bath for 30 minutes. To the mixture is added dropwise a solution of 2,6-dichloropyrazine (0.50 g) in tetrahydrofuran (5 ml) at the same temperature over a period of 15 minutes, and the mixture is stirred for one hour. The reaction mixture is poured into dry ice, and the mixture is stirred at room temperature for one hour. The reaction mixture is diluted with a 10% aqueous hydrochloric acid solution in order to adjust the pH value thereof to about 2, and then extracted with ethyl acetate. The combined organic layers are extracted with a saturated aqueous sodium hydrogen carbonate solution, and the aqueous extract is washed with ethyl acetate, acidified with a 10% aqueous hydrochloric acid, and extracted with ethyl acetate. The combined organic layer is washed with water and a saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue is triturated with a mixture of chloroform and hexane (1:1) to give 2-carboxy-3,5-dichloropyrazine (234 mg) as a slightly brown crystalline powder, m.p. 139-141 C., MS (m/z): 191 (M-H)-.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 4774-14-5, its application will become more common.

Reference:
Patent; Yamada, Koichiro; Matsuki, Kenji; Omori, Kenji; Kikkawa, Kohei; US2003/32647; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 5049-61-6, The chemical industry reduces the impact on the environment during synthesis 5049-61-6, name is Pyrazin-2-amine, I believe this compound will play a more active role in future production and life.

5, 6 , 7 , 8-tetrahydroimidazo [1, 2-a] pyrazine A29Stage 1. was added to a mixture of 2-aminopyrazin (25 g, 262.9 mmole), chloroacetaldehyde (50% in water, 50 ml, 394 mmole) and NaHCO3 (33.1 g, 394 mmole) and heated for 2 days at 1000C. The reaction mixture was then cooled to RT, saturated K2CO3 solution (100 ml) was added, and the mixture was washed with DCM. The organic phase was dried over sodium sulfate and then concentrated by evaporation to dryness . Purification was carried out by column chromatography on silica gel (DCM / methanol, 95:5 + 5% NH4OH [35%] .

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, Pyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GRUeNENTHAL GMBH; WO2009/90055; (2009); 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. 91476-80-1, name is 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine, A new synthetic method of this compound is introduced below., Recommanded Product: 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine

Production Example 6 1-(2-Hydroxyethyl)-6,8-difluoro-7-(5,6,7,8-tetrahydroimidazo[1,2-a]pyrazin-7-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (compound No. 10) Using 1-(2-hydroxyethyl)-6,7,8-trifluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid and 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine, the same procedure as in Production Example 1 was followed to yield the title compound. Melting point: 253-255 C. Elemental analysis (for C18 H16 F2 N4 O4.1/2H2 O)

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; Takeda Chemical Industries, Ltd.; US5519024; (1996); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 22047-25-2, 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. 22047-25-2, name is Acetylpyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Step 1: Preparation of 4,4-difluoro-1-(2-pyrazinyl)-butane-1,3-dione Ethyl difluoroacetate (2.23 g, 18 mmol) was placed in a 100 mL round bottom flask and dissolved in ether (10 mL). To the stirred solution was added 25 weight % sodium methoxide (4.68 g, 22 mmol) followed by acetylpyrazine (2.00 g, 16 mmol). After two hours stirring at room temperature, a precipitate formed and THF (10 mL) was added to the reaction. The reaction was stirred an additional 25.9 hours, then treated with 3N HCl (10 mL). The organic layer was collected, washed with brine (20 mL), dried over MgSO4, and concentrated in vacuo and recrystallized from methylene chloride/isooctane to give the diketone as a brown solid (2.23 g, mp 103-110 C., 68%). 1 H NMR (CDCl3) 300 MHz 14.00 (br s, 1H), 9.31 (d, J=1.4 Hz, 1H), 8.76 (d, J=2.4 Hz, 1H), 8.68 (dd, J=1.4 Hz 2.4 Hz, 1H), 7.20 (s, 1H), 6.03 (t, J=54.0 Hz, 1H); 19 F NMR (CDCl3) 300 MHz: -127.16 (d); M+200.

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, Acetylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; G.D. Searle & Co.; US5466823; (1995); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 41110-29-6, name is Methyl 3-methylpyrazine-2-carboxylate, 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 41110-29-6, category: Pyrazines

To a stirred solution of the product of Step A (0.9 g, 5.9 mmol) in MeOH (20 mL) was added hydrazine hydrate (1.5g, 23.7 mmol) at RT. The mixture was stirred at 60 overnight. The mixture was concentrated and the residue was dissolved into EtOAc (30 mL) . The organic phase was washed with brine, dried over Na 2SO 4 and concentrated under reduced pressure. The residue (460 mg, yield: 51.1%) was used into next Step directly. MS: M/e 153 (M+1) +.

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; BEIGENE, LTD.; ZHANG, Guoliang; ZHOU, Changyou; (152 pag.)WO2019/196803; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 2423-65-6, The chemical industry reduces the impact on the environment during synthesis 2423-65-6, name is Pyrazine 1-oxide, I believe this compound will play a more active role in future production and life.

1) Take 0.25mmol of pyrazine nitrogen oxide,diphenyl disulfide 0.45mmol,Cu(AcO)2 0.125 mmol and potassium hydroxide 0.5 mmol,add 1 mL of toluene to make a mixture,the mixture was placed in a 5 ml Schlenk tube,heated in an oil bath at 130C,after 48 hours of reaction,cool to room temperature to obtain the reaction solution;2) Concentrate the reaction solution to obtain a concentrate, and use a mixed solvent of ethyl acetate and petroleum ether in a volume ratio of 1:3 as a developing agent, and use silica gel as an adsorbent to perform thin layer chromatography to obtain 16 mg of the target product. The target product yield of this example is 32%, and the target product is subjected to nuclear magnetic characterization.

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, Pyrazine 1-oxide, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Henan Agricultural University; Wu Zhiyong; Zhao Mingqin; Lai Miao; (13 pag.)CN108017581; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 914452-71-4, A common heterocyclic compound, 914452-71-4, name is 2-Bromo-6-methylpyrazine, molecular formula is C5H5BrN2, 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 a stirred solution of 1 (100mg, 577.99mumol), 2 (168mg, 924.79mumol) in DMF:water (5mL, 1:1), it was added Na2CO3 (141 mg, 1.33 mmol) and 1 mg of PdNP at room temperature. The resulting reaction mixture was heated at 100 C for 15 min, after completion of reaction reaction mass was cooled to room temperature, diluted with H2O (10 mL) and extracted with EtOAc (3×15 mL). The combined organic layer was washed with brine solution, dried over Na2SO4, filtered and concentrated under reduced pressure to afford crude compound, which was triturated with pet ether to delivered 3 (120 mg, 90%) as off-white solid. 1H NMR (500 MHz, CDCl3) delta: 8.79 (d, J = 5.0 Hz, 1H), 8.34 (d, J = 5.0 Hz, 1H), 7.70 – 7.51 (m, 1H), 7.04 – 6.92 (m, 1H), 4.09 – 3.89 (m, 2H), 2.66 – 2.59 (m, 1H); 13C NMR (126 MHz, CDCl3) delta 153.01, 151.40, 150.56, 149.51, 141.92, 138.57, 129.50, 119.66, 111.23, 109.83, 56.02, 56.01, 21.76; LC-MS (ESI): 231.16 (M+H).

The synthetic route of 914452-71-4 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Bendre, Ameya D.; Kodam, Kisan M.; Patil, Viraj P.; Terdale, Santosh S.; Waghmode, Suresh B.; Journal of Organometallic Chemistry; vol. 909; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 77112-52-8,Some common heterocyclic compound, 77112-52-8, name is Ethyl imidazo[1,2-a]pyrazine-2-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.

Procedure for step-3 :To a well stirred suspension of the ester obtained from step-1 (1Og, 52.3 ?imol) in dioxane (400 ml) was added lithium borohydride (2 eqv) at 25C and the resulting reaction mixture was allowed to stir at the same temperature for 10 minutes. It was then warmed to 60C and kept at this temperature for for 20 minutes ( . Higher temperature and more reaction time reduce the yield and quality of reaction) . Reaction mixture was then cooled to 0C, acidified with IN HCl and dioxane was completely evaporated under reduced pressure. Residue was taken in dichloromethane (200 ml) , TEA ( 4eqv) and Boc-anhydride ( 1.2 eqv) was added to it and the resulting reaction mixture was allowed to stir at 250C for 16 hrs . Organic layer was washed with water and brine and finally dried over sodium sulfate. Evaporation of organic layer gave the crude product which was purified by column chromatography (70% ethyl acetate in hexane) . Yield : 27%

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-2-carboxylate, its application will become more common.

Reference:
Patent; GRUeNENTHAL GMBH; WO2009/90055; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 59489-39-3, 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 59489-39-3 as follows.

3,5-dibromo-6- chloropyrazin-2-amine (Rz = Cl) was prepared according to Organic Letters, 17(15), 3888- 3891; 2015. 6-amino-3,5-dibromopyrazine-2-carbonitrile (Rz = CN) was prepared as follows.6-Aminopyrazine-2-carbonitrile (ig, 8.3 mmol) was dissolved in dichloromethane (15 mL). To this solution, NBS (2.96g, 16.65 mmol, 2 eq.) was added, and the reaction mixture was stirred at room temperature overnight (16 h). The reaction mixture was poured into water and extracted with dichloromethane, dried over MgSO4, filtered, and concentrated under reduced pressure. The residue was purified using silica gel chromatography with Heptane/EtOAc as eluent providing 6-amino-3,5-dibromopyrazine-2-carbonitrile (Rz = CN)

According to the analysis of related databases, 59489-39-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PROMEGA CORPORATION; HALL, Mary; KIRLAND, Thomas; MACHLEIDT, Thomas; SHAKHMIN, Anton; WALKER, Joel, R.; (141 pag.)WO2018/22865; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem