Month: November 2020

4858-85-9, 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. 4858-85-9, name is 2,3-Dichloropyrazine, This compound has unique chemical properties. The synthetic route is as follows.

A mixture of 2,3-dichloropyrazine (1.2 g, 8.05 mmol) and morpholine (700 mg, 8.05 mmol) in ethanol (10 mL) was refluxed overnight. The mixture was cooled to RT, diluted with ethyl acetate (30 mL) and washed with water (30 mL) followed by brine (40 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue obtained was purified by silica gel column chromatography to yield 1.57 g of the desired product; 1H NMR (300 MHz, CDC13) delta 3.46 (t, 7 = 6.9 Hz, 4H), 3.86 (t, 7 = 6.9 Hz, 4H), 7.91 (d, 7 = 2.4 Hz, 1H), 8.12 (d, 7 = 2.4 Hz, 1H).

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; GLENMARK PHARMACEUTICALS S.A.; DAS, Sanjib; GHARAT, Laxmikant Atmaram; HARDE, Rajendra Laxman; SHELKE, Sandeep Yadunath; PARDESHI, Shailesh Ramesh; THOMAS, Abraham; KHAIRATKAR-JOSHI, Neelima; SHAH, Daisy Manish; BAJPAI, Malini; (181 pag.)WO2017/21879; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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. 55557-52-3

(90 g, 645 mmol), CH3COOH (1 L) and Raney Ni (20 g) were added to a 2 Lautoclave successively. A reaction was carried out in the autoclave while the reaction solution was stirred under ahydrogen pressure of 1 MPa for 48 hours at atmospheric temperature. After the reaction was completed, the reactionsolution was filtered through diatomite, and a solution of HCl in MeOH (200mL, 6.0N) was used to wash diatomite The filtrate after being concentrated was poured into toluene and the obtained system was stirred, and was thenconcentrated again. The obtained mixture was stirred in MTBE (methyl tert-butyl ether) and was filtered. The filtercake was stirred in MTBE and MeOH and was then filtered to obtain intermediate 2 (40g, yield: 35%) as a brownsolid. LCMS showed a molecular ion peak (M+1) 144.0.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 55557-52-3, its application will become more common.

Reference:
Patent; Hangzhou Sanyintai Pharmaceutical Technology Co., Ltd.; Yin, Jianming; YIN, Jianming; LV, Yubin; LI, Bangliang; (36 pag.)EP3480199; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

123-32-0, 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 123-32-0 as follows.

A method for preparing 5-methylpyrazine-2-carboxylic acid by catalytic oxidation, firstly, diatomaceous earth, manganese chloride, sodium tungstate,Cobalt nitrate and distilled water were added to the reactor at the following element mass ratio: diatomaceous earth: Mn:W:Co:H2O=1:0.09:0.08:0.14:50,Magnetically stirring at room temperature to make it dispersed and uniformly adsorbed, and then removing water by evaporation.Adding a liquid silica sol with a total mass of 5% of the solid sample and kneading it into a small granular sample of 1-2 mm.The mixture was placed in a muffle furnace and calcined in an air atmosphere at 600 C for 5 hours to obtain Mn-W-Co/diatomaceous earth-supported catalyst particles.10 g of Mn-W-Co/diatomaceous earth catalyst particles were packed into a fixed bed microreactor reaction tube, and the reactor was heated to 330 C.The reaction raw material 2,5-dimethylpyrazine was introduced into a fixed bed reaction tube by bubbling with high-temperature steam at 10 ml/min.Oxygen is introduced into the reaction tube separately at 20 ml/min to cause catalytic oxidation of 2,5-dimethylpyrazine in the catalytic bed.The 5-methylpyrazine-2-carboxylic acid is produced and taken out of the reaction tube by water vapor, condensed, crystallized, and collected.Analysis of 5-methylpyrazine-2-carboxylic acid by gas chromatographyThe yield was 75.6%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 123-32-0, and friends who are interested can also refer to it.

Reference:
Patent; Lanzhou University; Dong Zhengping; (6 pag.)CN109369544; (2019); 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. 19838-08-5, name is 3-Methylpyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows., 19838-08-5

3-Methyl-pyrazin-2-ylamine (2) (109 mg, 1.0 mmol) , benzaldehyde (106 mg, 1.0 mmol) and 3-chloro- phenylisonitrile (138 mg, 1.0 mmol) were dissolved in a mixture of dry methanol (2.0 mL) and trimethyl orthofor- mate (2.0 mL) under argon. The mixture was stirred at 6O0C for 3 hours, then cooled to rt . An analytically pure sample of 3 was obtained from the crude product using preparative HPLC.

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; ESBATECH AG; WO2006/131003; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common compound: 23611-75-8, name is Methyl 6-chloropyrazine-2-carboxylate, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 23611-75-8

Step 1 :Preparation of6-(6-chloropyrazin-2-yl)-N2,N?-bis (4,4-dfluorocyclohexyl)-1,3,5-triazine-2,4-diamine. To a mixture of methyl 6-chloropyrazine-2-carboxylate (300mg, 1. 74mmol) and N?,N5-di-(4,4-difluorocyclohexanamine)- biguanide (700 mg, 2.10 mmol)in MeOH (8 mL) was added MeONa (340 mg, 6.28 mmol).The reaction mixture was stirred at r.t. overnight, and then partitioned between EtOAc (30 mL) and 1120(3OmL). The organic layerwas separated, washed with brine (30 mL), dried over anhydrous Na2SO4, and concentrated and purified by standard methods to afford the desired product. ?H NIVIR (400MHz, DMSO-d6) 9.48 – 9.32 (m, 111), 8.93 (d,J811z, 111), 7.92 – 7.59 (m, 211), 4.15 -3.95(m, 211), 2.08 – 1.60(m, 1611).LCMS:m/z 460(M+H).

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, 23611-75-8, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; AGIOS PHARMACEUTICALS, INC.; KONTEATIS, Zenon D.; POPOVICI-MULLER, Janeta; TRAVINS, Jeremy M.; ZAHLER, Robert; CAI, Zhenwei; ZHOU, Ding; WO2015/3640; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

122-05-4, Name is Pyrazine-2,5-dicarboxylic acid, 122-05-4, 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.

Pyrazine-2,5-dicarboxylic acid (0.58 g; 3.42 mmol), anhydrous HOBt (0.69 g; 5.13 mmol) and l-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.98 g: 5.13 mmol) were added to 5 ml of DCM. 2-(5-(3,4-dichlorophenyl)furan-2-yl)- ethanamine hydrochloride (1.0 g; 3.42 mmol) and DIPEA (0.89 ml; 5.13 mmol) were dissolved in 5 ml of DCM and added dropwise to the previous mixture. The reaction mixture was stirred overnight after which pyrazine-2,5-dicarboxylic acid (0.58 g; 1.59 mmol) and DIPEA (0.60 ml; 3.42 mmol) were added and the mixture was again stirred for 5 h. Anhydrous HOBt (0.69 g; 5.13 mmol), l-(3-dimethylaminopropyl)-3- ethylcarbodiimide hydrochloride (0.98 g: 5.13 mmol) and DIPEA (0.89 ml; 5.13 mmol) were again added to drive the reaction to completion. After overnight stirring the mixture was diluted with 20 ml of DCM and washed with 3×10 ml water. The organic phase was dried over Na2S04, filtered and used as such without further purification.

Statistics shows that Pyrazine-2,5-dicarboxylic acid is playing an increasingly important role. we look forward to future research findings about 122-05-4.

Reference:
Patent; ORION CORPORATION; WOHLFAHRT, Gerd; TOeRMAeKANGAS, Olli; SALO, Harri; HOeGLUNG, Lisa; KARJALAINEN, Arja; KNUUTTILA, Pia; HOLM, Patrick; RASKU, Sirpa; VESALAINEN, Anniina; WO2011/51540; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

36070-80-1, The chemical industry reduces the impact on the environment during synthesis 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

The starting 5-chloropyrazine-2-carboxylic acid (317 mg, 2 mmol) was converted to5-aminopyrazine-2-carboxylic acid (1) by substitution reaction with 25% (m/m) aqueous solutionof ammonia (3 mL). The reaction was carried out 10 mL microwave pressurized vials with stirring(reaction temperature: 100 C, reaction time: 30 min, power output: 80 W). The reaction was repeated20 times to yield reasonable quantity of the starting acid. Once the reaction was completed, the vials content was put onto Petri dish and heated above a water bath with intermittent stirring until a drysolid was obtained (ammonium salt of the product). To get the free acid form, the ammonium salt wasdissolved in water and drop-wise acidified with 10% hydrochloric acid to reach pH of 4. The mixturewas then left to cool down in room temperature for 5 min then kept in the fridge for 15 min. The formedfree acid crystals were filtered off by filtration paper with suction and left to dry overnight. After itwas dried, the resulting 5-aminopyrazine-2-carboxylic acid (1) was esterified in several microwavepressurized vials; 3 mL of anhydrous propanol and 2 drops of concentrated sulfuric acid were added to278 mg (2 mmol) of compound 1 in each vial. The esterification was carried out in microwave reactor(reaction temperature: 100 C, reaction time: 1 h, power output: 80 W). The completion of reaction wasmonitored by TLC in system hexane/ethyl acetate (EtOAc) (1:3). The ester was then purified by flashchromatography using gradient elution 40 to 100% EtOAc in hexane.

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

Reference:
Article; Bouz, Ghada; Juhas, Martin; Niklova, Pavlina; Jand?ourek, Ond?ej; Paterova, Pavla; Ek, Ji?i Janou; T?mova, Lenka; Kovalikova, Zuzana; Kastner, Petr; Dole al, Martin; Zitko, Jan; Molecules; vol. 22; 10; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 1458-18-0, name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, molecular formula is C6H5Cl2N3O2, 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. 1458-18-0

A. 2-Amino-5,6-dichloro-3-(hydroxymethyl)pyrazine To 70 ml of dry tetrahydrofuran there was added 2-amino-5,6-dichloro-3-(methoxycarbonyl)pyrazine (8.8 g; 0.04M), potassium borohydride (2.7 g; 0.05M), and lithium chloride (2.1 g; 0.05M), and the mixture was stirred at room temperature overnight (17 hours). The reaction mixture was then diluted with about 200 ml of water and chilled, after which the product crystallized, was filtered and dried (5.3 g).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1458-18-0, its application will become more common.

Reference:
Patent; Merck & Co., Inc.; US4507299; (1985); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 5521-58-4, name is 5-Methylpyrazin-2-amine, 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 5521-58-4, 5521-58-4

DMF (2 drops) was added to a solution of3-{[(LS}1-methyl-2-(methyloxy)ethyl]oxy}-5- [(phenylmethyl)oxy]benzoic acid (6.0 g, 19.0 mmol) and oxalyl chloride (1.99 mL, 22.8 mmol) in DCM (40 mL) The mixture was stirred at ambient temperature for 2 hours and the DCM and excess oxalyl chloride evaporated in vacuo. The residual acid chloride was dissolved in DCM and added dropwise to 2-amino-5 methylpyrazine [Tett lett. 2002, 9287-90] (2.28 g, 19.8 mmol) and pyridine (2.56 mL, 38 mmol) in DCM (40 mL), at 0C. Stirred at ambient temperature for 24 hours. The DCM was evaporated in vacuo, and the residue partitioned between ethyl acetate (100 mL) and IN hydrochloric acid (50 mL). The ethyl acetate layer was washed sequentially with saturated aqueous sodium hydrogen carbonate (50 mL) and brine (50 mL), dried (MgS04), and evaporated in vacuo. The residue was chromatographed on silica, eluting with a gradient of 30-100% ethyl acetate in isohexane, to give the desired compound (7.6 g) ‘H NMR No. (CDC13): 1.32 (d, 3H), 2.55 (s, 3H), 3.40 (s, 3H), 3.50-3.62 (m, 2H), 4.60 (m, 1H), 5.10 (s, 2H), 6.75 (s, 1H), 7.09 (m, 1H), 7.13 (m, 1H), 7.32-7.46 (m, 5H), 8.13 (s, 1 H), 8.38 (s, 1H), 9.55 (s, 1H). m/z 408 (M+H)+

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

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2005/121110; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

38557-72-1, Adding a certain compound to certain chemical reactions, such as: 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, 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 38557-72-1.

0.39 g of 2-chloro-3,5-dimethylpyrazine, 0.87 g of 2-(3-diphenylaminophenyl)-1,3,2-dioxaborolane which was obtained in Step 1, 0.30 g of sodium carbonate, 0.013 g of bis(triphenylphosphine)palladium(II) dichloride (abbreviation: Pd(PPh3)2Cl2), 10 mL of water, and 10 mL of acetonitrile in a recovery flask equipped with a reflux pipe. The air in the flask was then replaced by argon. This reaction container was heated by microwave irradiation (2.45 GHz, 100 W) for 20 minutes. After that, the reaction container was cooled to 50 C. or lower. Then, water was added to the reaction solution, and the organic layer was subjected to extraction with dichloromethane. The obtained organic layer was washed with water and dried with magnesium sulfate. After the drying, the solution was filtered. The solvent of this solution was distilled, and the obtained residue was purified by silica gel column chromatography using a mixed solvent of dichloromethane and ethyl acetate as a developing solvent, thereby obtaining the objective pyrazine derivative Hdm5dpappr (white powder, 11% yield). Note that the microwave irradiation was performed using a microwave synthesis system (Discover, produced by CEM Corporation). The synthesis scheme of Step 2 is shown by (b-1).

According to the analysis of related databases, 38557-72-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Semiconductor Energy Laboratory Co., Ltd.; US2012/165523; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem