Tag: M.W=100-200

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. 95-89-6, name is 3-Chloro-2,5-dimethylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C6H7ClN2

Intermediate 18: 3,6-d imethyllyrazin-2-amineAmmonia in water (3 mL, 48.5 mmol) was added to 3-chloro-2,5-dimethylpyrazine (0.121 mL, 1 mmol) and the mixture heated by microwaves to 165 C for 7 hours. Following LCMS analysis, the reaction was then reheated to 165 C for a further 16 hours, by microwaves. After cooling, thesolvent was removed under a stream of nitrogen and the crude redissolved in dichloromethane (20mL). Water (25 mL) was added and the mixture basified to pHl4 using sodium hydroxide solution(18 N). The organic layer was removed and the aqueous layer extracted with dichloromethane (5 x25 mL). The organic phases were combined and dried using a hydrophobic frit, then evaporated invacuoto give the title product (109 mg). This was used directly in the next step with no furtherpurification. LCMS (2 mm, high pH) Rt 0.47 mi m/z (ESj 124 (M+H).1H NMR (400 MHz, CHLOROFORM-o) O ppm 7.73 (5, 1 H), 4.42 (br. s., 2 H), 2.37 (5, 3 H), 2.35 (5, 3H).

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 95-89-6.

Reference:
Patent; GLAXO GROUP LIMITED; BIRAULT, Veronique; CAMPBELL, Amanda, Jennifer; HARRISON, Stephen; LE, Joelle; SHUKLA, Lena; WO2013/160419; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 36070-75-4, name is 5-Chloropyrazine-2-carbonitrile, 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 36070-75-4, Quality Control of 5-Chloropyrazine-2-carbonitrile

A 0.5-2 mL microwave vial was evacuated and back filled with N2. rac-1-((2S,3R,4R)-4-amino-6-(3,6-dihydro-2H-pyran-4-yl)-2,3-dimethyl-3,4-dihyd roquinolin- I (2H)-yl)ethanone (for a preparation seeIntermediate 150, 23.3 mg, 0.078 mmol) in N-methyl-2-pyrrolidone (NMP) (0.7 mL) was then added. To this was added 5-chloropyrazine-2-carbonitrile (21.65 mg, 0.155 mmol), and DIPEA (0.041 mL, 0.233 mmol) and the resultant solution then heated to 150 C for 30 mm in a microwave. The reaction mixture was filtered through a cotton wool plug directly into an LCMS vial and was thenpurified by MDAP (Formic). The appropriate fraction was collected and concentrated in vacuo to afford the desired product as a yellow gum which was still impure. Therefore the crude product was taken up in DCM and loaded onto a silica cartridge (10 g). This was purified by flash chromatography, eluting with 0-100% EtOAc/cyclohexane. The appropriate fractions were collected and concentrated in vacuo to afford the desired product as a colourless oil (6.3 mg, 0.016 mmol, 20.13%). LCMS (2 mm Formic): Rt = 0.90 mi [MH] = 404.

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

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO.2) LIMITED; AMANS, Dominique; ATKINSON, Stephen John; HARRISON, Lee Andrew; HIRST, David Jonathan; LAW, Robert Peter; LINDON, Matthew; PRESTON, Alexander; SEAL, Jonathan Thomas; WELLAWAY, Christopher Roland; WO2014/140076; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 59489-32-6, name is 5-Chloro-2,3-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 59489-32-6, Formula: C6H7ClN2

A. 2-(2-Dimethylaminoethylamino)-5,6-dimethyl pyrazine. 2-chloro-5,6-dimethylpyrazine (12.8 g., 0.09 mole) is added to unsym-dimethylethylenediamine (26 g., 0.295 mole) containing cuprous chloride (0.25 g.) and the mixture is heated for 48 hours in an oil bath maintained at 135-140 C. On cooling, 50 ml of water and a single molar excess of 10N sodium hydroxide are added. The mixture is extracted with methylene chloride. The organic extracts are backwashed with saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated under vacuum. The residual oil is dissolved in hexane, filtered and reconcentrated to obtain the product oil (15.8 g., 0.081 mole).

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; Merck & Co., Inc.; US4144338; (1979); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 54608-52-5,Some common heterocyclic compound, 54608-52-5, name is 2-Hydrazinopyrazine, molecular formula is C4H6N4, 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 vigorously stirred mixture of alpha-bromonitroalkane (0.50 mmol), heteroaryl hydrazine (0.60 mmol, 1.2 equiv), potassium iodide (1.0 mmol, 2.0 equiv) and potassium carbonate (1.0 mmol, 2.0 equiv) in 1,2-dimethoxyethane (5.0 mL) was added a solution of urea hydrogen peroxide in 1,2-dimethoxyethane/water (4:1) (0.50 M solution, 1.0 mL, 0.50 mmol, 1.0 equiv) over 2 h via syringe pump at r.t. After the addition was complete, the mixture was stirred for an additional 4 h. Aqueous sodium thiosulfate was then added and the mixture was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate, and concentrated in vacuo. The residue was purified by flash column chromatography to give pure fused triazole.

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

Reference:
Article; Tokumaru, Kazuyuki; Bera, Kalisankar; Johnston, Jeffrey N.; Synthesis; vol. 49; 20; (2017); p. 4670 – 4675;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 23611-75-8,Some common heterocyclic compound, 23611-75-8, name is Methyl 6-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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.

To a stirring solution of methyl 6-chloropyrazine-2-carboxylate (2.50 g, 14.49 mmol) in THF (50 mL) was added methylmagnesium bromide 3M in diethyl ether (12.07 mL, 36.2 mmol) at 0 C. The resulting mixture was stirred at ambient temperature for 30 minutes. The reaction mixture was diluted with saturated NH4Cl (100 mL) and extracted with ethyl acetate (3 x 100 mL). The combined organic layers were washed with brine (50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (Redisep-24 g, 0.40 % EtOAc/n-hexane) to obtain Intermediate 105A (0.70 g, 28.00%). 1H NMR (400 MHz, DMSO-d6) delta ppm 1.44 (s, 6 H), 5.58 (br,s 1 H), 8.66 (s, 1 H), 8.86 (s, 1 H). LCMS: The compound did not ionize well.

The synthetic route of 23611-75-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; YADAV, Navnath Dnyanoba; BHIDE, Rajeev S.; BORA, Rajesh Onkardas; GUNAGA, Prashantha; PANDA, Manoranjan; PRIESTLEY, Eldon Scott; RICHTER, Jeremy; (444 pag.)WO2018/222795; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 32974-92-8, 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. 32974-92-8, name is 1-(3-Ethylpyrazin-2-yl)ethanone, This compound has unique chemical properties. The synthetic route is as follows.

Example 1862-(N-isopropylbenzyl)aminoethyl-2-(3-ethyl)-pyrazylketone 8656 2-acetyl-3-ethylpyrazine (151 mg), benzylisopropylamine (149 mg), and paraformaldehyde (40 mg) were reacted in dioxane (0.2 ml) at 130 C. for 2 hours.NMR (CDCl3) 1.1-1.2 (m, 6H), 2.7 (m, 1H), 3.1 (m, 4H), 3.7 (m, 2H), 7-7.2 (m, 1H)TG 29 (3 mumol) 16 (10 mumol) 14 (30 mumol)SOCE 0 (10 mumol) 0 (30 mumol) 10 (100 mumol)IICR 70 (10 mumol) 90 (30 mumol) 100 (100 mumol)

The chemical industry reduces the impact on the environment during synthesis 1-(3-Ethylpyrazin-2-yl)ethanone. I believe this compound will play a more active role in future production and life.

Reference:
Patent; Japan Science and Technology Agency; US2012/277423; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 16298-03-6, 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 16298-03-6 as follows.

To a solution of methyl 3-amino- pyrazine-2- carboxylate (5.00 g, 32.7 mmol) in 1,2-dimethoxyethane (80 mL) were added ?2 (4.14 g, 16.3 mmol), copper(I) iodide (1.87 g, 9.80 mmol) and cesium iodide (8.48 g, 32.7 mmol) undernitrogen. Then isoamyl nitrite (13.2 mL, 98.0 mmol) was added dropwise at 20 °C. The reaction was stirred at 75 °C for 2 h, then quenched with water (100 mL). The aqueous layer was extracted with EtOAc (100 mL x 3). The combined organic layers were washed with brine (30 mL), dried over anhydrous MgSO4 and filtered. The filtrate was concentrated in vacuo to give a residue, which was purified by silica gel chromagraphy eluting withPE/EtOAc (5i02, PE: EtOAc = 1: O1O:1, v/v) to give the title compound. MS (ESI) mlz:264.7 [M+Hj ?H NMR (400MHz, DMSO-d6) oe = 8.71 (d, J=2.2 Hz, 1H), 8.63 (d, J2.0Hz, 1H), 3.93 (s, 3H)

According to the analysis of related databases, 16298-03-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MERCK SHARP & DOHME CORP.; MILLER, Michael; CHOBANIAN, Harry, R.; HE, Shuwen; HAO, Jinsong; PIO, Barbara; GUO, Yan; XIAO, Dong; (213 pag.)WO2018/118670; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 6164-79-0, 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 6164-79-0 as follows.

To methyl pyrazine-2-carboxylate (3.35 g, 24.3 mmol) in EtOH (60 mL) was added calcium chloride (4.03 g, 36.4 mmol) followed by sodium borohydride (1.38 g, 36.4 mmol). The reaction mixture was stirred at 23C for 5 h. The mixture was quenched with a mixture of acetic acid (4.20 mL, 72.8 mmol) and water (1.31 mL, 72.8 mmol), and stirred for 30 min. The mixture was filtered through a pad a silica gel, and the pad was washed with 5-10% MeOH/DCM containing 0.3% conc. NH3 (aq). The combined filtrates were concentrated in vacuo, and the crude residue was purified by FCC (SiO2, elution with 0-10% MeOH/DCM)to provide 2.01 g (75%) of pyrazin-2-ylmethanol. 1H NMR (400 MHz, d6-DMSO): d ppm 8.71 (m, 1H), 8.56 (dd, 1H), 8.54 (d, 1H), 5.61 (t, 1H), 4.63 (d, 2H); LCMS (Method E): tR= 0.56 min, m/z 111.3 (M+H)+. Step 3: 2-(Chloromethyl)pyrazine

According to the analysis of related databases, 6164-79-0, the application of this compound in the production field has become more and more popular.

Reference:
Patent; VENENUM BIODESIGN LLC; LETOURNEAU, Jeffrey J; COLE, Andrew G; MARINELLI, Brett A; QUINTERO, Jorge G; (329 pag.)WO2017/214359; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common heterocyclic compound, 19745-07-4, name is 2,5-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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. 19745-07-4.

A mixture of K2C03 (3.4 g, 0.24 mmol), 2,4-difluoro-3-hexyloxy-5-(2-pyridyl)phenyl boronic acid (2.04 g, 6.1 mmol) and 2,5-dichloropyrazine (719 mg, 2.5 mmol) in a mixture of water (20 ml_), toluene (40 ml_) and ethanol (2 ml_) was deoxygenated by bubbling N2 through the mixture for 20 minutes. Pd(PPh3)4 (250 mg, 0.24 mmol) was then added and the mixture was heated under refluxed for 15 hours. Brine (40 ml_) was added and the phases were separated. The aqueous layer was extracted with ethyl acetate (3 x 20 ml_). The combined organic layers were dried over MgS04, filtered and evaporated to dryness. The product was purified by column chromatography (Si02, Petroleum ether/EtOAc, from 9/1 to 6/4). Colourless solid (630 mg, 38percent). 1 H NMR (400 MHz, CDCI3) delta 9.15 (d, 1 H, J = 2.0 Hz), 8.74 (ddd, 2H, J = 1.2 Hz, J = 5.2 Hz, J = 6.4 Hz), 8.39 (dd, 2H, J = 8.4 Hz), 7.78 (m, 4H), 4.23 (t, 4H, J = 6 Hz), 1.83 (q, 4H, J = 7.2 Hz), 1.34 (m, 4H), 1.36 (m, 8H), 0.90 (t, 6H, J = 7.2 Hz). 13C NMR (100 MHz, CDCI3) delta 152.40, 150.05, 146.85, 144.58, 144.46, 136.63, 125.49, 125.31 , 124.40, 124.32, 122.86, 121.34 (m), 75.57, 31.32, 30.10, 25.46, 22.68, 14.13.

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

Reference:
Patent; UNIVERSITY OF NORTHUMBRIA AT NEWCASTLE; KOZHEVNIKOV, Valery; LANOE, Pierre-Henri; WO2014/23972; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 33332-28-4, 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. 33332-28-4, name is 2-Amino-6-chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows.

To a solution of 2-amino-6-chloropyrazine (5 g, 38.60 mmol) in a mixture of anhydrous chloroform (120 mL), anhydrous acetonitrile (12 mL) and anhydrous methanol (12 mL) was addedslowly, at 0CC, NBS (7.56 g, 42.45 mmol, 1.1 eq.) and the mixture was warmed to room temper-ature and continuously stirred for 1 h. The excess solvent was removed in vacuo and the obtained crude material (light brown solid) was purified by column chromatography (Hexane/DCM/MeOH = 50/50/0 then 0/1 00/0 then 0/95/5) to afford 5-bromo-6-chloropyrazin-2-amine(6.34 g, 30.42 mmol, 79percent) as white crystals. ESI-MS: 209.90 [M+H]+. 1 H NMR (300 MHz,CDCI3) 6 7.69 (s, 1 H), 4.78 (br s, 2H).

The chemical industry reduces the impact on the environment during synthesis 2-Amino-6-chloropyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; SELVITA S.A.; BOBOWSKA (NEE WITKOWSKA), Aneta; GALEZOWSKI, Michal; NOWAK, Mateusz; COMMANDEUR, Claude; SZEREMETA-SPISAK, Joanna; NOWOGRODZKI, Marcin; OBARA, Alicja; DZIELAK, Anna; LOZINSKA, Iwona; DUDEK (NEE SEDLAK), Marcelina; JANIGA, Anita; REUS, Jacek; WRONOWSKI, Marek; ZASTAWNA, Magdalena; RADZIMIERSKI, Adam; SWIRSKI, Mateusz; ZACHMANN, Julian; FABRITIUS, Charles-Henry; PORTER, Rod; FOGT, Joanna; (276 pag.)WO2019/2606; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem