Month: September 2021

Adding a certain compound to certain chemical reactions, such as: 912773-21-8, name is 2-Bromo-5-chloropyrazine, 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 912773-21-8, Application In Synthesis of 2-Bromo-5-chloropyrazine

A mixture of 5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2- yl)-2-[l-(trifluoromethyl)cyclobutoxy]pyridine (2.1 g, 6.12 mmol), 2-bromo-5-chloro- pyrazine (1.18 g, 6.12 mmol), Pd(dppf)Cl2(671.68 mg, 0.92 mmol) and CS2CO3(3.99 g, 12.24 mmol) in l,4-Dioxane (20 mL) and Water (2 mL)was stirred at 60 C for 6 hours under N2. After cooling to room temperature, the mixture was concentrated to give the residue. The residue was diluted with H2O (20 mL), and the mixture was extracted with EtOAc (20 mL x 2). The combined organic phase was washed with water (20 mL) and brine (40 mL), dried over Na2S04, filtered and concentrated to give the crude product. The crude product was purified by flash chromatography on silica gel (EtOAc in PE = 0% to 1% to 10%) to give the product (1.5 g, 4.263mmol, 70% yield) as an oil. ‘H NMR (CDCI3, 400MHz) 5H = 8.80 – 8.72 (m, 2H), 8.63 (d, 1H), 8.25 (dd, 1H), 6.91 (d, 1H), 3.01 – 2.83 (m, 2H), 2.78 – 2.62 (m, 2H), 2.18 – 1.84 (m, 2H).

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, 2-Bromo-5-chloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; PRAXIS PRECISION MEDICINES, INC.; GRIFFIN, Andrew, Mark; MARRON, Brian, Edward; MARTINEZ BOTELLA, Gabriel; REDDY, Kiran; WITTMANN, Marion; (0 pag.)WO2019/232209; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, 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 4744-50-7, category: Pyrazines

General procedure: Pyrazine-2,3-dicarboxylic anhydride (1.0 g, 6.7 mmol) was dissolved in tetrahydrofuran (40 mL)in an Erlenmeyer flask and the corresponding substituted aniline (6.7 mmol, 1 equiv.) was added in one dose. The reaction mixture was stirred for 1 hour at laboratory temperature. Water (30 mL) was added into the mixture followed by the saturated aqueous solution of NaHCO3 until pH 6 to form thecorresponding 3-(phenylcarbamoyl)pyrazine-2-carboxylic acid 1-18. Obtained crystals were filtered off and washed with water. The progress of the procedure was monitored by TLC eluted with thesystem water/butanol/acetic acid 5:4:1.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2,3-Pyrazinecarboxylic anhydride, and friends who are interested can also refer to it.

Reference:
Article; Semelkova, Lucia; Jano?cova, Petra; Fernandes, Carlos; Bouz, Ghada; Jand?Ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; Molecules; vol. 22; 9; (2017);,
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

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

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

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 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 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

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

87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, 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: C5H4Br2N2O

Example 123c 5-Bromo-3-(1-ethyl-1H-pyrazol-4-ylamino)-1-methylpyrazin-2(1H)-one 123c A 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer and reflux condenser was charged with 123b (500 mg, 4.5 mmol), 3,5-dibromo-1-methylpyrazin-2(1H)-one (2.40 g, 9.0 mmol), DIPethyl acetate (3 mL), and isopropanol (50 mL). The mixture was heated at 100° C. for 2 h. It was then cooled to room temperature and filtered. The filtrate was concentrated under reduced pressure to afford 123c (802 mg, 60percent) as a white solid. MS-ESI: [M+H]+ 298.0

The synthetic route of 87486-34-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GENENTECH, INC.; Crawford, James John; Ortwine, Daniel Fred; Wei, BinQing; Young, Wendy B.; US2013/116246; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem