Category: 98-97-5

Electric Literature of 98-97-5, 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. 98-97-5 name is Pyrazine-2-carboxylic acid, 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.

General procedure: To a solution of an appropriate substituted carboxylic acid (10 mmol) in CHCl3 (50 mL) was added thionyl chloride (3.6 mL, 50 mmol), dropwise over 10 min. The resulting solution was refluxed for 8 h and then concentrated in vacuo. The residual light brown oil was dissolved in THF (50 mL), diluted with a solution of 30% NH4OH (6 mL), and stirred at room temperature for an additional 2 h. At that point, saturated aqueous NaHCO3 (10 mL) was added and the reaction mixture was extracted with EtOAc (3 × 30 mL). The combined organic layer was washed with brine (50 mL), dried over anhydrous Na2SO4, and concentrated in vacuo. The crude amide was carried directly to the next step without further purification.

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

Some common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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 Pyrazine-2-carboxylic acid

Pyrazine-2-carboxylic acid (5 g, 40.3 mmol) was dissolved inMeOH (150 ml), and a few drops of H2SO4 were added. The resultingreaction mixture was refluxed for 2 h. Methanol was evaporated and the resulting reaction mixture was extracted withEtOAc, washed with saturated NaHCO3 solution, then with brineand dried over anhydrous Na2SO4. The solvent was removed invacuo to give the methyl pyrazine-2-carboxylate (5.5 g, yield98%). 1H NMR (CDCl3, 400 MHz) d 9.32 (d, 1H, J = 1.5 Hz), 8.78(d, 1H, J = 2.4 Hz), 8.73 (dd, 1H, J = 2.4, 1.5 Hz), 4.04 (s, 3H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 98-97-5, its application will become more common.

Reference:
Article; Lee, Young Hun; Lee, Jung Min; Kim, Sang Geon; Lee, Yong Sup; Bioorganic and Medicinal Chemistry; vol. 24; 12; (2016); p. 2843 – 2851;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 98-97-5, The chemical industry reduces the impact on the environment during synthesis 98-97-5, name is Pyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

Step 1 (esterification of pyrazine-2-carboxylic acid to yield methyl-pyrazine-2-carboxylate): To a 1L single-neck round-bottomed flask fitted with condenser and drying tube filled with silica gel was charged methanol (400 mL) with agitation at room temperature. Pyrazine-2-carboxylic acid (50.00 g, 402.90 mmol) was charged to the flask in one portion and the resulting slurry was vigorously stirred. Conc. sulfuric acid (0.25 mL) was charged to the slurry. The slurry was heated to reflux temperature and stirred at this temperature for 2 days. The resulting pale yellow solution was allowed to cool to room temperature. This process takes 90 minutes. Solid sodium bicarbonate (4.00 g, 47.62 mmol) was added to the solution in one portion and the slurry was stirred vigorously for 30 minutes. The suspension was filtered and the filtrate was transferred to a 2L single-neck round-bottomed flask and concentrated to about half volume in vacuo a 35 C. Toluene (1200 mL) was added to the methanol solution and a Dean-Stark trap fitted with drying tube was attached. The solution was heated at atmospheric pressure (external oil bath a120 C.) and the first 300 mL solvent fraction was run off and discarded. The Dean-Stark trap was removed and the reaction solution was concentrated in vacuo a45 C. to a volume of 300 mL. The organic phase containing the desired methyl-pyrazine-2-carboxylate was filtered to remove solid particulates and used directly in the next step as a solution in toluene (a small analytical sample was removed and concentrated in vacuo a 35 C. to yield a pale brown solid, m.p. 60-61 C., structure 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, Pyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

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

Adding a certain compound to certain chemical reactions, such as: 98-97-5, name is Pyrazine-2-carboxylic acid, 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 98-97-5, name: Pyrazine-2-carboxylic acid

To a solution of Pyrazine-2-carboxylic acid (295mg, 2. [1MMOL,] leq) and triethylamine [(765UL,] 5.4mmol, 2.6eq) in THF (6ml) at [0 C] was added dropwise diphenylphophoryl azide [(L.] 4ml, 2. [8MMOL,] [1.] 3eq). The mixture was stirred under nitrogen at [0 C] for 30 minutes, then warmed to RT and stirring continued for a further 2 hours. The reaction mixture was concentrated under vacuum and purified by flash chromatography [(90/10-60/40] [ISO-HEXANE/ETOAC)] to afford the title compound as white solid (265mg, yield=78%). 1H NMR (400 MHz, [CDC13)] [6] 9.14 (d, 1H, J=1.2) ; 8.50 (dt, 1H, J=1.2, 0.4), 2.62 (s, 3H, broad).

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; MILLENIUM PHARMACEUTICALS, INC.; WO2003/101444; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 98-97-5,Some common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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.

Diphenyl phosphorylazide (8.6 g) was added dropwise to a solution of pyrazine-2- carboxylic acid (3 g) in THF (30 ml) and TEA (9 ml) and the resulting reaction mixture was stirred at RT for 2 hours. On completion, THF was removed under reduced pressure to give a residue, which was further purified by column chromatography (SiO2, gradient 10-40 % EtOAc/n-hexane) yielding the desired product (2.5g, 70%).

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

Reference:
Patent; SENTINEL ONCOLOGY LIMITED; WO2007/144579; (2007); 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. 98-97-5, name is Pyrazine-2-carboxylic acid belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below. category: Pyrazines

Synthesis of methyl pyrazine-2-carboxylate: To a stirred solution of pyrazine-2-carboxylic acid (5 g, 40.29 mmol) in MeOH (20 mL) was added concentrated H2S04 (1 mL) drop wise and stirred under reflux for 5 h. The reaction mixture was cooled to RT; volatiles were evaporated under reduced pressure. The residue was diluted with water and basified to pH~ 8.5 using NaHC03 and extracted with EtOAc. Combined organic layer was dried over sodium sulphate, filtered and concentrated in vacuo to afford methyl pyrazine-2-carboxylate (3.5 g, 63.63%) as an off- white solid. 1H-NMR (DMSO d6, 400 MHz): delta 9.21 (s, 1H), 8.91 (d, 1H), 8.82 (d, 1H), 3.92 (s, 3H); TLC: 50% EtOAc/Hexane (Rf: 0.4).

The synthetic route of 98-97-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ENVIVO PHARMACEUTICALS, INC.; RIPKA, Amy; SHAPIRO, Gideon; MCRINER, Andrew; WO2012/40230; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 98-97-5, name is Pyrazine-2-carboxylic acid, 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 98-97-5, category: Pyrazines

To a solution of pyrazine-2-carboxylic acid (1 g, 8.06 mmol) in DMF (5 mL), 4-methyl-3-thiosemicarbazide (933 mg, 8.87 mmol) was added. DIPEA (2.5 mL, 14.5 mmol) was added drop-wise at RT, then the mixture was cooled in an ice-bath before adding T3P (50% w/wEtOAc) (7.1 mL, 12.09 mmol). The reaction was stirred at RT on. NaOH 4 M solution (7.5mL) was added (resulting pH=8). The reaction was diluted with EtOAc and the two resulting phases were separated (the upper organic layer eliminated). The pH was increased to 11 NaOH 4and the mixture heated to 70 C for 2h. The yellow solution was then cooled in an ice bath and 37% HC1 was slowly added till pH 5. A precipitate formed. It was filtered under vacuum, washed with water and Cy and dried to obtain 1.44 g of title compound (p20, y%92). MS(m/z): 194.1 [MH]t

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; INDIVIOR UK LIMITED; CREMONESI, Susanna; MICHELI, Fabrizio; SEMERARO, Teresa; TARSI, Luca; (318 pag.)WO2017/21920; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 98-97-5,Some common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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.

REFERENCE EXAMPLE 8-42-pyrazinemethanol (Compound CD)Step 1; To methanol (8.0 mL), thionyl chloride (2.08 mL) was added dropwise under a nitrogen atmosphere at -10 C. and the mixture was stirred at the same temperature for 30 minutes. To this, 2-pyrazinecarboxylic acid (1.00 g, 8.06 mmol) was added at the same temperature and the mixture was stirred at room temperature for 72 hours. The reaction mixture was concentrated, a saturated aqueous sodium bicarbonate solution was added to the residue, and extraction with ethyl acetate was performed, followed by washing with brine and drying over anhydrous sodium sulfate. The solvent was evaporated off under reduced pressure, and the residue was purified by silica gel column chromatography (chloroform/methanol 19/1) to give methyl 2-pyrazinecarboxylate (969 mg, yield: 87%).1H-NMR (270 MHz, CDCl3, delta); 4.06 (s, 3H), 8.74 (dd, J=1.3, 2.3 Hz, 1H), 8.79 (d, J=1.3 Hz, 1H), 9.34 (d, J=2.3 Hz, 1H).

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

Reference:
Patent; Amishiro, Nobuyoshi; Fukuda, Yuichi; Kinpara, Keisuke; Mie, Motoya; Tagaya, Hisashi; Takahashi, Takeshi; US2011/237584; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

98-97-5, name is Pyrazine-2-carboxylic acid, belongs to Pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. HPLC of Formula: C5H4N2O2

General procedure: The N-hydroxysuccinimideesters of pyrazinecarboxylic acid and (5)-(+)-ibuprofen were prepared by dissolving the starting acid (0.200 g, 1.0 equiv) in dry tetrahydrofuran. With stirring at 0 C, NHydroxysuccinimide (1.0 equiv) was added followed by N,N-dicyclohexylcarbodiimideequiv). The mixture was warmed to ambient temperature and stirred for 24 h. The N,Ndicyclohexylurea was removed by filtration and the filtrate was concentrated to afford a solid that was purified by column chromatography.[001481 2, 5-Dioxopyrrolidin-1-yl pyrazine-2-carboxylate 14. The cmde white solid was purified by column chromatography (Si02, acetone/dichloromethane, 1:4) to give a white solid (0.2757 g, 77%). Mp: 161 – 164 C. ?H NMR (300 MHz, CDC13): oe 9.40 (d, J= 1.41H), 8.90 (d, J= 2.3 Hz, 1H), 8.83 (dd, J= 2.4, 1.5 Hz, 1H), 2.95 (s, 4H). ?3C NMRMHz, CDC13): oe 168.9, 159.6, 149.3, 147.1, 145.2, 140.2, 25.8. JR (neat): 3501, 3324, 3276, 3078, 2929, 2851, 1875, 1806, 1785, 1703, 1653, 1626, 1571, 1533, 1468, 1449, 1420, 1399, 1360, 1306, 1260, 1243, 1203, 1183, 1153, 1075, 1060, 1048, 1025, 1011, 995,892, 876, 853, 811, 782, 764, 713 cmi. HRMS calcd. for C9H8N304 [M+Hj 222.0509, found 222.0502.

The synthetic route of 98-97-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; THE REGENTS OF THE UNIVERSITY OF CALIFORNIA; BOARD OF TRUSTEES OF MICHIGAN STATE UNIVERSITY; PIRRUNG, Michael, C.; BAKAS, Nicole, A.; BACHMANN, Andre; (89 pag.)WO2017/156471; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 98-97-5, name is Pyrazine-2-carboxylic acid, 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 98-97-5, COA of Formula: C5H4N2O2

To a solution containing 2-pyrazine carboxylic acid (10 g, 80.5 mmol) in dichloromethane (150 mL) was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride EDC (18.5 g, 96.6 mmol) and 1-hydroxybenzotriazole HOBT (13.05 g, 96.6 mmol) and the resulting solution stirred at 25 C. for 30 minutes. Then 1-cyclohexylglycine methyl ester (16.7 g, 80.5 mmol) and Hunig’s base (31.24 g, 241 mmol) was added and the reaction mixture stirred for 2 hours. The reaction mixture was partitioned between water and dichloromethane. The organic layer was removed and dried over MgSO4, filtered and concentrated in vacuo and purified via flash chromatography using ethyl acetate/hexane (20/80 to 30/70) to give a foam (13.3 g, 60%). The product of the previous reaction (6.54 g, 24 mmol) was dissolved in ethanol and treated with 1N sodium hydroxide (35.4 mL, 35.3 mmol) at 25 C. for 4 hours. The mixture was neutralized with 10% HCl to pH 4 and extracted with dichloromethane. The organic layer was removed and dried over MgSO4, filtered and concentrated in vacuo to afford a foam (5 g, 81%).

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

Reference:
Patent; Abbott Laboratories; US2010/29686; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem