Month: February 2021

Related Products of 4774-14-5, These common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, 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: [Li(TMP)Zn(tBu)2] 1 was made according to the literature procedure2 on a 0.4 mmol scale in THF solution. To this solution 2-methoxypyridine (0.042 mL, 0.4 mmol) was added and the resultant light orange reaction allowed to stir at room temperature for 2 hours. Next the solution was cooled to 0C and quenched with I2 (508 mg, in 1 mL THF) and allowed to stir for 1 hour. Next a 10% solution of Na2S2O3 was added until bleaching and the product extracted with DCM (3 x 1 mL). The combined organic extracts were dried over MgSO4 and the solvent removed under reduced pressure. The residue was purified by SiO2 chromatography using Heptane:DCM as eluent (20:80–>40:60) to give 3-iodo2-methoxypyridine 2a as a colourless oil (87.1 mg, 92% yield).

Statistics shows that 2,6-Dichloropyrazine is playing an increasingly important role. we look forward to future research findings about 4774-14-5.

Reference:
Article; Blair, Victoria L.; Blakemore, David C.; Hay, Duncan; Hevia, Eva; Pryde, David C.; Tetrahedron Letters; vol. 52; 36; (2011); p. 4590 – 4594;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 95-58-9, The chemical industry reduces the impact on the environment during synthesis 95-58-9, name is 2-Chloro-3-methylpyrazine, I believe this compound will play a more active role in future production and life.

EXAMPLE 3; 7-r (3R)-3-Amino-4-(2s45-trifluorophenyl) butanoyll-8-methyl-3-(trifluoromethyl) 5, 6, 7, 8-tetrahydro-1, 2, 4-triazolof4, 3-alpyrazine, trifluoroacetate salt; Step A. 2-Hydrazino-3-methylpyrazine; To 15 mL of hydrazine hydrate at ambient temperature was added dropwise 5 g (42.9 mmol) of 2-chloro-3-methylpyrazine. The resultant mixture was heated to 120 C for 45 min then cooled in a refrigerator for 48 h. The yellow precipitate was collected by vacuum filtration and dried under vacuum to give 1.6 g (30%) of the title compound which was used without further purification. 1H NMR (400 MHz, CD30D) 8 7.94 (d, 1H, J=3.0 Hz), 7.63 (d, 1H, J=3.0 Hz), 2.32 (s, 3H).

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-Chloro-3-methylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK & CO., INC.; WO2003/82817; (2003); A2;,
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. 32587-10-3, name is 3-Aminopyrazine-2-carboxamide, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 32587-10-3

Step 2: Synthesis of Intermediate C’ as described in the general scheme: 2-amino-3-amido-5-bromopyrazine A mixture of B’ (210 g, 1.52 mM), acetic acid (630 mL) and sodium acetate tri-hydrate (310 gm, 2.28 mM) is warmed up to 50 C. To this solution is added bromine (93.43 mL, 1824 mM) in acetic acid (105 mL) in 1.5 hrs and the mixture is stirred for 30 min at 50-55 C. The reaction mixture is cooled to 15 C., water (2.1 L) is added over 20-30 min and the resulting suspension is stirred for another 30 min. The Solid is isolated by filtration, washed with water (210 mL*2) and dried at 45 C. under vacuum to afford C’, used in the next step without further treatment.

According to the analysis of related databases, 32587-10-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; WIGERINCK, Piet Tom Bert Paul; ANDREWS, Martin James Inglis; De WEER, Marc Maurice Germain; SABOURAULT, Nicholas Luc; KLUGE, Stefan Christian; US2011/118269; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 59489-71-3, 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. 59489-71-3, name is 2-Amino-5-bromopyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

5-bromo-piperazin-2-amine 4g, 22.99mmol, 1.00N was dissolved in 1,4-dioxane 68 mL and a mixed solution of 46mL ofanhydrous methanol, and then were added 3- (trifluoromethyl) phenylboronic acid 4.46g, 23.48mmol, 1.02N, sodium carbonate4.88g, 46.04mmol, 2.00N and Pd (PPh 3) 4 532mg, 0.46mmol, 0.02N, the whole system is heated to 135 C, stirred overnight,concentrated under reduced pressure Shrink, and finally by silica gel column chromatography, eluting with petroleum ether /ethyl acetate = 5: 1 to give yellow Colored solid of 5- (3- (trifluoromethyl) phenyl) piperazin-2-amine 4.4g, yield 80%

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

Reference:
Patent; Shaanxi University of Technology; JIANG, MIN; LU, JIUFU; (17 pag.)CN103755695; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 24241-18-7, These common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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.

To a stirred suspension of 2-amino-3,5-dibrompyrazine (427 g, 1688 mmol) in water (6.4 L)/ THF (482 mL), at rt was added bromacetaldehyde-diethylacetal (998 g, 5065 mmol) in one portion. After stirring under reflux for 4 h, the clear orange solution was stirred for an additional 15 h at rt. The suspension was filtered, and the remaining solid was washed with MeOH (2 L) and dried in vaccuo at 60 C. to yield 6,8-dibromo-imidazo[1,2-a]pyrazine as an off-white solid (500 g, 107% with residual MeOH): 1H-NMR (300 MHz, d6-DMSO): delta=9.02 (s, 1H), 8.23 (d, 1H), 7.89 (d, 1H) ppm. UPLC-MS: RT=0.80 min; m/z 277.9 [MH+]; required MW=276.9.

The synthetic route of 24241-18-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER INTELLECTUAL PROPERTY GMBH; Koppitz, Marcus; Klar, Ulrich; Jautelat, Rolf; Kosemund, Dirk; Bohlmann, Rolf; Bader, Benjamin; Lienau, Philip; Siemeister, Gerhard; US2013/267527; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 143591-61-1, These common heterocyclic compound, 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, 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.

Example 103; To a solution of compound 102 (13.0 g, 55.9 mmol) in DMSO (150 mL) was added sodium methanethiolate (4.70 g, 67.08 mmol) as a DMSO solution (100 mL) at room temperature. The reaction mixture was stirred at 100 C. for 16 hours. The mixture was cooled to 25 C. and added to a brine solution (300 mL), and extracted with 10% IPA/dichloromethane (300 mL, 3¡Á). The combined organic layer was dried over anhydrous sodium sulfate and concentrated. Purification by column chromatography (SiO2, ethyl acetate/hexanes (1:1)) afforded compound 103 as a yellow solid 10 g (70%). 1H-NMR (400 MHz, DMSO-d6 delta 8.15 (d, 1H), 7.88 (d, 1H), 7.83 (s, 1H), 2.6 (s, 3H).

The synthetic route of 143591-61-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Schering Corporation; US2007/117804; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Recommanded Product: 33332-25-1

Diisobutylaluminium hydride (1.0 M in toluene; 6.4 mL, 6.40 mmol) was added dropwise to a cooled solution of methyl 5-chloropyrazine-2-carboxylate (690 mg, 4.00 mmol) in THF (13.6 mL) at -55 C. The reaction was stirred under these conditions for 1 hour and then quenched by addition of saturated aqueous NH4C1 (25 mL) and EtOAc (25 mL). An emulsion formed and 2N aqueous HC1 was added to clear the emulsion (5 mL). The layers were separated, and the aqueous layer was extracted with EtOAc. The organic layerwas washed with saturated aqueous sodium chloride, dried over magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified by flash silica chromatography, elution gradient 0 to 50% EtOAc in heptane. Product fractions were evaporated to dryness to afford 5-chloropyrazine-2-carbaldehyde (385 mg, 68%) as a beige solid. ?H NMR (500 MHz, CDC13, 27 C) 8.75 (1H, d), 8.96 (1H, d), 10.15 (1H, d).

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference:
Patent; ASTRAZENECA AB; SCOTT, James, Stewart; MOSS, Thomas, Andrew; YANG, Bin; VARNES, Jeffrey, Gilbert; O’DONOVAN, Daniel, Hillebrand; NISSINK, Johannes, Wilhelmus, Maria; HUGHES, Samantha, Jayne; BARLAAM, Bernard, Christophe; WU, Dedong; BROO, Dan, Anders; (224 pag.)WO2018/19793; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 4744-50-7, 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. 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

General procedure: A solution of substituted benzyl amine (10 mmol) and an acid anhydride (10 mmol) in glacial acetic acid (15mL) was heated under reflux for 4h. After the evaporation of the reaction mixture to dryness under reduced pressure, the residue was neutralised by a solution of sodium bicarbonate (4%) until effervescence ceased. The precipitate obtained was washed with water, dried and re-crystallised from an appropriate solvent.

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

Reference:
Article; Alanazi, Amer M.; El-Azab, Adel S.; Al-Suwaidan, Ibrahim A.; Eltahir, Kamal Eldin H.; Asiri, Yousif A.; Abdel-Aziz, Naglaa I.; Abdel-Aziz, Alaa A.-M.; European Journal of Medicinal Chemistry; vol. 92; (2015); p. 115 – 123;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 33332-25-1, 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 33332-25-1 as follows.

(5-chloropyrazin-2-yl)methyl methanesulfonate; [00369] To a solution of 5-chloropyrazine-2-carboxylic acid (3.21 g, 20.3 mmol) in diethyl ether (20 mL) and methanol (20.0 mL) was added a 2M solution in diethyl ether of trimethylsilyldiazomethane (20.3 mL, 40.5 mmol). A vigorous bubbling was observed initially, and LCMS after 30 minutes indicated that the reaction was complete.Concentration of the reaction mixture afforded methyl 5-chloropyrazine-2-carboxylate (3.53 g, 20.5 mmol, 101% yield) as a tan solid. This material was shown to be >95% pure by NMR analysis and was used in the subsequent step without any purification. lH NMR (400 MHz, CDC13) delta (ppm): 9.09 (s, 1H), 8.70 (s, 1H), 4.04 (s, 3H).[00370] To a 0 C solution of methyl 5-chloropyrazine-2-carboxylate (3.50 g, 20.3 mmol) in tetrahydrofuran (101 mL) was added a 1M solution in tetrahydrofuran of diisobutylaluminum hydride (42.6 mL, 42.6 mmol). The reaction was stirred at 0 C for 2 hours, after which it was quenched by the addition of methanol (2 mL). To this mixture was added saturated sodium-potassium tartrate solution, and the resulting reaction mixture was extracted with ethyl acetate (3 x 100 mL), dried (sodium sulfate), filtered and concentrated to brown residue. Purification was achieved by column chromatography on silica gel (Luknova 120 g, 20 mL/min) using 30 to 100% ethyl acetate in hexanes over 60 minutes to afford (5- chloropyrazin-2-yl)methanol (1.45 g, 10.0 mmol, 50 % yield) as a tan solid. NMR (400 MHz, CDC13) a (ppm): 8.56 (s, 1H), 8.45 (s, 1H), 4.84 (s, 3H), 2.79 (br. s, 1H).[00371] To a 0 C solution of (5-chloropyrazin-2-yl)methanol (648 mg, 4.48 mmol) in dichloromethane (12 mL) was added triethylamine (1.87 mL, 13.5 mmol) followed by dropwise addition of methanesulfonyl chloride (0.699 mL, 8.97 mmol). After 20 minutes, analysis by LCMS indicated the complete conversion to the mesylate product. The reaction mixture was concentrated to afford (5-chloropyrazin-2-yl)methyl methanesulfonate (787 mg, 3.53 mmol, 79% yield) as an oil. The material was used crude in the next step without further purification.

According to the analysis of related databases, 33332-25-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; IRONWOOD PHARMACEUTICALS, INC.; HUDSON, Colleen; BARDEN, Timothy, C.; JIA, James; MERMERIAN, Ara; PENG, Bo; YANG, Jane; YU, Xiang, Y.; SPROTT, Kevin; WO2012/88469; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 1256921-67-1, 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. 1256921-67-1, name is Methyl 6-bromo-3-chloropyrazine-2-carboxylate belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

A mixture of 6-bromo-3-chloropyrazine-2-methylcarboxylate (2 g, 7.95 mmol), tert- butyl N-(4-methylpiperidin-4-yl)carbamate (1.87 g, 8.74 mmol), N,N-Diisopropylethylamine (6.57 mL, 39.7 mmol), and 40 mL of acetonitrile was allowed to stir in a sealed tube at 35 C for 2 hrs, followed by concentration under reduced pressure. The residue was extracted with EtO Ac/water, dried over magnesium sulfate, and concentrated under reduced pressure. The resulting product was submitted to the next step without further purification. XH NMR (500 MHz, Methanol-d4) delta 8.27 (s, 1H), 3.95 (s, 3H), 3.68 – 3.59 (m, 2H), 3.32 – 3.27 (m, 2H), 2.14 (d, J = 13.9 Hz, 2H), 1.59 (ddd, J = 14.1, 10.8, 4.1 Hz, 2H), 1.46 (s, 12H), 1.35 (s, 3H). LC-MS (ESI): m/z [M + H] Ci7H26BrN404 calculated 429.12, found 429.3

The synthetic route of Methyl 6-bromo-3-chloropyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; REVOLUTION MEDICINES, INC.; LI, Jie Jack; KOLTUN, Elena S.; GILL, Adrian Liam; BUCKL, Andreas; WON, Walter; AAY, Naing; MELLEM, Kevin; TZITZILONIS, Christos; JOGALEKAR, Ashutosh; CREGG, James Joseph; (177 pag.)WO2019/75265; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem