Month: November 2020

3149-28-8, Adding some certain compound to certain chemical reactions, such as: 3149-28-8, name is 2-Methoxypyrazine, 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 3149-28-8.

To a solution of 2-methoxypyrazine (5.0g, 45.4mmol), in 40ml of anhydrous THF was added tributyltin hydride (15.0mL, 54.9mmol) and the resulting solution stirred under nitrogen at 0C. Cyclohexylcarbonyl chloride (8.0mL, 59.8mmol) was added over 10min and stirring continued until reaction completion in 20min as determined by TLC (neutral alumina, EtOAc/hexanes (1/19, v/v)). A 1M solution of HCl in methanol (20.0mL) was then added to the reaction mixture that was stirred under nitrogen at 0C until reaction completion in 30min as determined by TLC (SiO2, EtOAc/hexanes (2/3, v/v). The reaction mixture was quenched with 50mL of water, extracted with ethyl acetate (3¡Á50mL), washed with saturated sodium bicarbonate (10mL), and then dried over anhydrous Na2SO4. Purification by silica gel flash column chromatography (100% hexanes: to remove tin by-products, followed by methanol / dichloromethane 2-5%) afforded 4-cyclohexanecarbonyl-1,2-dihydro-2-pyrazinone 3 (8.9g, 94%) as a pale yellow solid (mp 160-163C dec).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 3149-28-8.

Reference:
Article; Williams, Alfred L.; St. Hilaire, Valentine R.; Tetrahedron; vol. 73; 48; (2017); p. 6712 – 6717;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common compound: 767340-03-4, name is (2Z)-4-Oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazine-7(8H)-yl]-1-(2,4,5-trifluorophenyl)but-2-en-2-amine, 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. 767340-03-4

Into a 500 ml flask were charged chloro(l,5-cyclooctadiene)rhodium(I) dimer{[Rh(cod)Cl]2}(292 mg, 1.18 mmol) and (R,S) f-butyl Josiphos (708 mg, 1.3 mmol) under a nitrogen atmosphere. Degassed MeOH was then added (200 mL) and the mixture was stirred at room temperature for 1 h. Into a 4 L hydrogenator was charged the enamine amide 2^4 (118 g, 0.29 mol) along with MeOH (1 L). The slurry was degassed. The catalyst solution was then transferred to the hydrogenator under nitrogen. After degassing three times, the enamine amide was hydrogenated under 200 psi hydrogen gas at 50 0C for 13 h. Assay yield was determined by EtaPLC to be 93% and optical purity to be 94% ee. The optical purity was further enhanced in the following manner. The methanol solution from the hydrogenation reaction (18 g in 180 mL MeOH) was concentrated and switched to methyl t- butyl ether (MTBE) (45 mL). Into this solution was added aqueous Eta3PO4 solution (0.5 M, 95 mL).After separation of the layers, 3NNaOH (35 mL) was added to the water layer, which was then extracted with MTBE (180 mL + 100 mL). The MTBE solution was concentrated and solvent switched to hot toluene (180 mL, about 75 0C). The hot toluene solution was then allowed to cool to 0 0C slowly (5 – 10 h). The crystals were isolated by filtration (13 g, yield 72%, 98 – 99% ee); m.p. 114.1 – 115.7 0C. EPO lH NMR (300 MHz, CD3CN): delta 7.26 (m), 7.08 (m), 4.90 (s), 4.89 (s), 4.14 (m), 3.95 (m), 3.40 (m), 2.68(m), 2.49 (m), 1.40 (bs).Compound Z1I exists as amide bond rotamers. Unless indicated, the major and minor rotamers are grouped together since the carbon- 13 signals are not well resolved: 13c NMR (CD3CN): delta 171.8, 157.4 (ddd , JCF = 242.4, 9.2, 2.5 Hz), 152.2 (major), 151.8 (minor), 149.3(ddd; JCF = 246.7, 14.2, 12.9 Hz), 147.4 (ddd, /CF = 241.2, 12.3, 3.7 Hz), 144.2 (q, JCF= 38.8 Hz), 124.6 (ddd , JCF= 18.5, 5.9, 4.0 Hz), 120.4 (dd , JCF= 19.1, 6.2 Hz), 119.8 (q, JCF= 268.9 Hz), 106.2 (dd , /CF = 29.5, 20.9 Hz), 50.1, 44.8, 44.3 (minor), 43.2 (minor), 42.4, 41.6 (minor), 41.4, 39.6, 38.5 (minor), 36.9.

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, 767340-03-4, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK & CO., INC.; WO2006/119260; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

1458-18-0, A common heterocyclic compound, 1458-18-0, name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, molecular formula is C6H5Cl2N3O2, 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 solution of methyl 3-amino-5,6-dichloro-2-pyrazinecarboxylate (1.0 eq.) in 2-propanol (5 mL/mmol), an appropriate primary or secondary amine(3-6 eq.) was added, and the reaction mixture wasrefluxed for 2 h.10) The solution was cooled to roomtemperature, concentrated under reduced pressure, andthe residue was purified by silica-gel column chromatography(Wako gel C-200, 30-40% ethyl acetate/n-hexane) to afford the series 1 intermediate (yield:32-95%). The regioselectivity of the nucleophilicsubstitution at the 5-position of the pyrazine ring wasconfirmed by an X-ray structural analysis (Fig. S1).

The synthetic route of 1458-18-0 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Murai, Masatoshi; Habu, Sayako; Murakami, Sonomi; Ito, Takeshi; Miyoshi, Hideto; Bioscience, Biotechnology and Biochemistry; vol. 79; 7; (2015); p. 1061 – 1066;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 19745-07-4, name is 2,5-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. 19745-07-4

To a solution of NaH (0.755 g> 18.88 mmol) in THF (55 mL) was added benzyl mercaptan (1.5 mL, 12.68 mmol) at o ¡ãC. The reaction mixture was diluted with THF (20 mL) and stirred at o ¡ãC for 10 minutes. Then a solution of 2,5-dichloropyrazine (1.370 mL, 13.42 mmol) in THF (10 mL) was added dropwise. The reaction mixture was stirred at o ¡ãC for 1 hour, then warmed to room temperature and stirred for 16 hours. The reaction mixture was cooled to o ¡ãC, MeOH (1 mL) was added carefully and stirred for 5 minutes. Water (20 mL), then DCM (150 mL) was added and the biphasic mixture was passed through a phase separator. The organic phase was concentrated in vacuo. The crude product was purified by chromatography on silica gel (40 g column, 0-3percent EtOAc/isohexane) to afford the title compound (2.373 g, 72 percent) as a clear yellow oil. NMR (DMSO-d6) delta 8.68 (d, J = 1.5 Hz, lH), 8.49 (d, J = 1.5 Hz, lH), 7.43 – 7.39 (m, 2H), 7.34 – 7.29 (m, 2H), 7.28 – 7.23 (m, lH), 4.46 (s, 2H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 19745-07-4, its application will become more common.

Reference:
Patent; INFLAZOME LIMITED; COOPER, Matthew; MILLER, David; MACLEOD, Angus; VAN WILTENBURG, Jimmy; THOM, Stephen; ST-GALLAY, Stephen; SHANNON, Jonathan; (352 pag.)WO2019/8025; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

19745-07-4, 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 19745-07-4 as follows.

3.0 g of 2,5-dichloropyrazine,880 mg of sodium hydride (60percent, oil)And 50 mL of NMP,2.3 g of benzyl alcohol was added under ice cooling.The reaction mixture was allowed to warm to room temperature and stirred at room temperature for 5 hours.Water was added to the resulting reaction mixture, and the mixture was extracted with ethyl acetate. The obtained organic layer was washed with saturated brine, dried over anhydrous sodium sulfate,And concentrated under reduced pressure. The obtained residue was subjected to silica gel chromatography,3.1 g of Intermediate 1 represented by the following formula was obtained.Intermediate 1

According to the analysis of related databases, 2,5-Dichloropyrazine, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SUMITOMO CHEMICAL COMPANY LIMITED; SAKAMOTO, EMIKO; NISHIMURA, SHINYA; (242 pag.)JP2018/24669; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

41270-66-0, 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. 41270-66-0, name is 5-Chloro-2,3-diphenylpyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Trimethylamine (33% ethanol solution, 358 g, 2.0 mol) was added to ethyl acetate (1.3 L) of 5-chloro-2,3-diphenylpiperazine (266 g, 1.0 mol)And stirred at room temperature for 48 hours.A large number of solids are present.filter,The solid was washed with ethyl acetate (2 x 50 mL)Dried in high vacuum to give 283.5 g of a white solid,The yield was 87%.

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; Suzhou Guohang Pharmaceutical Technology Co., Ltd.; Mei, Desheng; (11 pag.)CN106467496; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

41270-66-0, 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. 41270-66-0, name is 5-Chloro-2,3-diphenylpyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To the stirred mixture of 5-chloro 2-3 diphenyl pyrazine (100 g, 0.375 mol) & 4-isopropyl amino butane-1-ol (172.17 g, 1.31 mol) was added at room temperature. The resultant reaction mixture was heated at 180-185C and maintain at same temperature for 24 hrs. After completion of reaction by HPLC analysis, cool the reaction mass and diluted it with ethyl acetate (1000 ml), purified water (1500 ml) and product was extracted : in ethyl acetate further aqueous layer was rewashed with ethyl acetate (500 ml). After combining the both ethyl acetate layers, wash it with 5% sodium bicarbonate (1000 ml) to remove the hydroxyl impurity formed during the reaction followed by washing of 10% sodium chloride solution (1000 ml). Ethyl acetate layer was concentrated under reduced pressure to obtain thick syrup of compound (4). Obtained thick syrup was diluted with ethyl acetate (20 ml) and n-heptane (500 ml) was added to the diluted mass and stirred for 60-90 min. the resultant isolated solid was filtered and washed with n-heptane (100 ml), suck dried and dried the solid under vacuum at 35-40 C for 3-4 hrs. [Yield = 95.0 g; Purity (HPLC) = 91.5%]

The synthetic route of 5-Chloro-2,3-diphenylpyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MEGAFINE PHARMA (P) LTD.; MATHAD VIJAYAVITTHAL THIPPANNACHAR; DODDAPPA PRALHAD ANEKAL; KARDILE PRITESH BHIMRAJ; PADAKI SANTHOSH AMBADAS; GAIKWAD BAPUSAHEB SHRIHARI; SHINDE GORAKSHANATH BALASAHEB; (63 pag.)WO2017/42828; (2017); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

36070-80-1,Some common heterocyclic compound, 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, molecular formula is C5H3ClN2O2, 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.

5-(Cyclopropylmethoxy)pyrazine-2-carboxylic acid A solution of 5-chloropyrazine-2-carboxylic acid (1.00 g, 6.31 mmol), cyclopropyl carbinol (1.00 mL, 12.4 mmol) and potassium tert-butoxide (2.00 g, 17.8 mmol) in dimethylformamide (20.0 mL) is heated at 100 C. for 3 hours. The reaction is cooled to room temperature, quenched with 1M hydrochloric acid. The mixture is extracted with ethyl acetate and isopropyl alcohol/chloroform (1/10), dried over magnesium sulfate, filtered, and concentrated under reduced pressure to give the title compound (1.10 g, 90%) as a grayish solid. This acid is used directly without further purification.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5-Chloropyrazine-2-carboxylic acid, its application will become more common.

Reference:
Patent; GREEN, Steven James; HEMBRE, Erik James; MERGOTT, Dustin James; SHI, Yuan; WATSON, Brian Morgan; WINNEROSKI, JR., Leonard Larry; US2014/371212; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

33332-29-5, 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. 33332-29-5 name is 2-Amino-5-chloropyrazine, 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: A magnetically stirred solution of xanthate (2.0 equiv) and pyrazine (1.0 equiv) in 1, 2-dichloroethane (1.0mmol/mL according to the xanthate) was refluxed for 15min under a flow of nitrogen. Then dilauroyl peroxide (DLP) was added portionwise (20mol % according to the xanthate) every hour until total consumption of one substrate. The reaction mixture was then cooled to room temperature and the solvent was evaporated under reduced pressure. Unless otherwise specified, the crude product was purified by flash chromatography on silica gel.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-5-chloropyrazine, and friends who are interested can also refer to it.

Reference:
Article; Huang, Qi; Qin, Ling; Zard, Samir Z.; Tetrahedron; vol. 74; 40; (2018); p. 5804 – 5817;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

1458-01-1, Adding some certain compound to certain chemical reactions, such as: 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, 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 1458-01-1.

General procedure: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate 2 (1 eq.) was combined with K2CO3 (10 eq.), the appropriate (het)aryl boronic acid (1.5 eq.) and Pd(PPh3)4 (5 mol%) in a two-neck round bottom flask. The flask was connected to a condenser and purged with nitrogen. A 4:1 mixture of anhydrous toluene: MeOH (60 mL) was added via syringe and the reaction mixture was heated at reflux for 0.5-18 h. The mixture was allowed to cool to room temperature and filtered through Celite (10 x 3 cm, eluting with 3 x 20 mL EtOAc). The filtrate was evaporated to dryness and the residue purified by silica gel flash column chromatography using EtOAc/pet spirit.

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 1458-01-1.

Reference:
Article; Buckley, Benjamin J.; Majed, Hiwa; Aboelela, Ashraf; Minaei, Elahe; Jiang, Longguang; Fildes, Karen; Cheung, Chen-Yi; Johnson, Darren; Bachovchin, Daniel; Cook, Gregory M.; Huang, Mingdong; Ranson, Marie; Kelso, Michael J.; Bioorganic and Medicinal Chemistry Letters; vol. 29; 24; (2019);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem