Month: March 2021

These common heterocyclic compound, 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]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. Formula: C7H3Cl2N3

Intermediate 25: 1 ,1-Dimethylethyl (3 ~)-3-fr(7-chloropyridor3,4-blpyrazin-5- yl)amino1methylV4-methyl-1-piperazinecarboxylate; 1 , 1-Dimethylethyl (3S)-3-(aminocarbonyl)-4-methyl-1-piperazinecarboxylate (0.5g, 2.055mmol) was dissolved in dry tetrahydrofuran (THF) (10ml) and borane- tetrahydrofuran complex (8ml, 8.00mmol) was added. The reaction was refluxed under nitrogen overnight. A further portion of borane-tetrahydrofuran complex (8ml, 8.00mmol) was added and the reaction was refluxed under nitrogen for a further 24h. After cooling, the reaction was cooled further in an ice bath and quenched by the addition of methanol (25ml) and 1 M HCI (5ml), stirred for 90min and left standing at room temperature for 2h. Ethyl acetate (25ml) was added and the layers were separated. The aqueous was extracted with ethyl acetate. The combined organics were dried using a hydrophobic frit and evaporated in vacuo to give a white solid (270mg). TLC (10% MeOH/DCM, KMn04) looked like starting material. The aqueous layer was neutralised with 2M NaOH and extracted with DCM (x3). The combined organics were washed with brine, dried using a hydrophobic frit and evaporated in vacuo to give 1 , 1-dimethylethyl (3f~)-3-(aminomethyl)-4-methyl-1- piperazinecarboxylate as a crude colourless oil (313mg). 1 , 1-dimethylethyl (3R)-3- (aminomethyl)-4-methyl-1-piperazinecarboxylate (143mg, 0.624mmol) and diisopropylethylamine (0.131 ml, 0.750mmol) were added to a solution of 5,7- dichloropyrido[3,4-b]pyrazine (100mg, 0.500mmol) in dry N-methyl-2-pyrrolidone (NMP) (2ml). The reaction was heated at 130C in the microwave for 30min. After cooling, the reaction was partitioned between ethyl acetate and water. The aqueous layer was extracted with ethyl acetate (x2). The combined organics were washed with brine, dried using a hydrophobic frit and evaporated to give an orange oil. The residue was loaded in dichloromethane and purified on silica (25g) using a 0-100% ethyl acetate/cyclohexane gradient. Appropriate fractions were combined and evaporated to give the title compound as yellow oil (162mg).LCMS (Method A): Rt = 1.2min, MH+ = 393/395

The synthetic route of 5,7-Dichloropyrido[3,4-b]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GLAXO GROUP LIMITED; ATKINSON, Francis Louis; ATKINSON, Stephen John; BARKER, Michael David; DOUAULT, Clement; GARTON, Neil Stuart; LIDDLE, John; PATEL, Vipulkumar Kantibhai; PRESTON, Alexander G; SHIPLEY, Tracy Jane; WILSON, David Matthew; WATSON, Robert J; WO2012/123312; (2012); A1;,
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. 22047-25-2, name is Acetylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., Formula: C6H6N2O

General procedure: To a stirred solution of aldehyde (10mmol) (4-(dimethylamino)benzaldehyde, 4-(1-piperidinyl)benzaldehyde, 4-(4-morpholinyl)benzaldehyde or 4-(diphenylamino)benz-aldehyde) in EtOH (75mL), ketone (20mmol) (2-acetylpyridine, 2-acetylthiazole or 2-acetylpyrazine) was added. Then KOH (1.54g, 27.5mmol) and NH3 (aq) (35mL) were added to the reaction mixture. The solution was stirred at room temperature for 24h. The solid was collected by filtration and washed with H2O. Recrystallization from ethanol (1, 4, 7, 10) or toluene (2, 3, 5, 6, 8, 9, 11, 12) afforded a crystalline solid.

According to the analysis of related databases, 22047-25-2, the application of this compound in the production field has become more and more popular.

Reference:
Article; Palion-Gazda, Joanna; Machura, Barbara; Klemens, Tomasz; Szlapa-Kula, Agata; Krompiec, Stanis?aw; Siwy, Mariola; Janeczek, Henryk; Schab-Balcerzak, Ewa; Grzelak, Justyna; Ma?kowski, Sebastian; Dyes and Pigments; vol. 166; (2019); p. 283 – 300;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 6863-74-7, name is 6-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 6863-74-7, COA of Formula: C5H2ClN3

Example IF (60 mg), 6-cyano-2-chloropyrazine (26 mg), KF (1 mg) and TEA (0.07 mL) were combined in a microwave tube and dissolved in ACN (2 mL). The reaction mixture was stirred in the micro wave oven at 130 C for 1 h. The reaction mixture was filtrated and purified by preparative HPLC to yield an off-white solid (9 mg; 12%). MS: m/z = 462.3 [M+H]+.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 6-Chloropyrazine-2-carbonitrile, and friends who are interested can also refer to it.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; BANNER, David; GRETHER, Uwe; HAAP, Wolfgang; KUEHNE, Holger; MAUSER, Harald; PLANCHER, Jean-Marc; WO2012/59507; (2012); 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. 41110-34-3, name is Ethyl 5-methylpyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Application In Synthesis of Ethyl 5-methylpyrazine-2-carboxylate

Ethyl 5-methyl-2-pyrazinecarboxylate (10.0 g, 60.18 mmol), benzoyl peroxide (1. 46 g, 6. 02 mmol) and N-bromo succinimide (11. 78 g, 66. 19 mmol) in 80 mL CCl4 was heated to reflux while a 75W tungsten lamp was shining on the reaction mixture. After 4h the reaction mixture was cooled and the precipitate filtered off. The red filtrate was concentrated and the residue redissolved in EtOAc and washed with sat’d NaHC03, 5% Na2S203, brine and the organics dried (Na2SO4), filtered and concentrated. Chromatography on silica gel using 1: 1 Hexanes: EtOAc eluted the product. After concentration the title compound (6.64 g, 27.08 mmol, 45% yield) was isolated as a yellow oil :’H NMR (CDC13, 400 MHz) 8 9.22 (s, 1H), 8.80 (s, 1H), 4. 58 (s, 2H), 4.49 (dd, J= 14.3, 7.1 Hz, 2H), 1.43 (t, J= 7.2 Hz, 3H).

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; SMITHKLINE BEECHAM CORPORATION; WO2003/76440; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 23688-89-3, name is 6-Chloropyrazine-2-carboxylic acid belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below. name: 6-Chloropyrazine-2-carboxylic acid

6-Ch[oropyrazine-2-carboxy[ic acid [CAS RN: 23688-89-3] (218 mg, 1.38 mmo[,1.0 eq) was disso[ved in 3 mL THF, and CDI (224 mg, 1.38 mmo[, 1.0 eq) wasadded. Then, the reaction mixture was heated to 70C for 2 h. Then, 1-(2-f[uoroethy[)piperidin-4-amine [CAS RN: 947263-70-9] (208 mg, 1.42 mmo[,1.03 eq) and triethy[amine (0.40 mL, 2.85 mmo[, 2.06 eq) as a so[ution in 2 mLTHF were added. The reaction mixture was heated to 70C for 1 h and was a[[owed to stand at rt for 1 day. Subsequent[y, the reaction mixture was partitioned between ethy[ acetate and water. The aqueous phase was extracted with ethy[ acetate and the combined organic [ayers were washed with brine. The phases were separated by the use of a Whatman fi[ter, the vo[ati[ecomponents were removed in vacuo and the crude materia[ was purified via preparative MPLC (Biotage Iso[era; 25 g SNAP cartridge: ethy[ acetate -> ethy[ acetate/ethanol. 4/1) to give 100 mg (24% yield of theory) of the title compound.UPLC-MS (Method 1): R = 0.52 mm; MS (EI0): m/z = 287 [M+H].

The synthetic route of 23688-89-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; BAeRFACKER, Lars; SIEMEISTER, Gerhard; HEINRICH, Tobias; PRECHTL, Stefan; STOeCKIGT, Detlef; ROTTMANN, Antje; WO2015/113927; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 63744-22-9, A common heterocyclic compound, 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, molecular formula is C6H3Br2N3, 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.

Intermediate Example 10-1 : Preparation of 6,8-dibromo-3-iodo-imidazo[1 ,2- aj yrazineTo a stirred solution of intermediate example 1 -1 (8.7 g g, 31 .4 mmol) in DMF (210 mL) was added NIS (7.42 g, 33 mmol, 1 .05 eq) in one portion at rt. After 18 h stirring at 60 C, the solvent was removed in vaccuo and the residue was taken up in DCM and washed with water and saturated sodium thiosulfate solution. The organic phase was dried over sodium sulphate, filtered and the solvent was evaporated to yield 9.46 g (74.8 %) 6,8-Dibromo-3-iodo-imidazo[1 ,2-a]pyrazine: 1H- NMR (300 MHz, CDC ): delta = 8.22 (1 H, s), 7.91 (1 H, s) ppm

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; BAYER PHARMA AKTIENGESELLSCHAFT; KOPPITZ, Marcus; KLAR, Ulrich; JAUTELAT, Rolf; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; WO2012/80234; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 87486-34-8,Some common heterocyclic compound, 87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, molecular formula is C5H4Br2N2O, 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 2a-j (10 mmol, 1.0 eq) , 3,5-dibromo-1-methylpyrazin-2(1H)-one (2.95 g, 11 mmol, 1.1 eq) and DIEA (3.3 mL,20 mmol, 2.0 eq) in MeCN (20mL) was stirred at 80 ¡ãC for 5 hours. After cooling to room temperature, thesolvent was removed in vacuo, and the residue was purified using silica gelchromatography to give the title compounds, yield 72-85percent.

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

Reference:
Article; Yang, Jianhong; Du, Jiatian; Huang, Chong; Wang, Tianqi; Huang, Luyi; Yang, Shengyong; Li, Linli; Bioorganic and Medicinal Chemistry Letters; vol. 29; 13; (2019); p. 1609 – 1613;,
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. 54013-07-9, name is 5-Methoxypyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows., Formula: C5H7N3O

2-Chloro-3-nitro-5-(trifluoromethyl)pyridine (500 mg) was dissolved in 1,2-dimethoxyethane (7.4 ml), and thereto were added 5-methoxypyrazine-2-amine (414 mg), tris(dibenzylidene acetone)dipalladium (0) (101 mg), potassium phosphate (843 mg) and 2-dicyclohexylphosphino-2′-(N,N-dimethylamino)biphenyl (87 mg), and the mixture was heated to 100 C. After the mixture was stirred all day and all night, it was kept standing to cool to room temperature, and water and chloroform were added thereto. After an insoluble material was filtrated, the organic layer was separated. After the organic layer was concentrated, the residue was purified by the silica gel column chromatography affording the compound 2 (502 mg).MS m/z 316[M+H]+, APCI(+)

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 54013-07-9.

Reference:
Patent; Mitsubishi Tanage Pharma Corporation; US2012/258951; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 6705-33-5, 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. 6705-33-5, name is Pyrazin-2-ylmethanol belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

200 mg of the product of Step A (0.281 mmol), 61.8 mg pyrazin-2-ylmethanol (0.562 mmol) and 147 mg PPh3 (0.562 mmol) were dissolved in 2 mL dry toluene, then 129 mg ditertbutyl azodiearboxylate (0.562 mmol) was added. The mixture was stirred at 50C under nitrogen until no further conversion was observed. The volatiles were evaporated under reduced pressure and the crude intermediate was purified via flash chromatography using EtOAc and MeOH as eluents.

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

Reference:
Patent; LES LABORATOIRES SERVIER; VERNALIS (R&D) LIMITED; KOTSCHY, Andras; SZLAVIK, Zoltan; CSEKEI, Marton; PACZAL, Attila; SZABO, Zoltan; SIPOS, Szabolcs; RADICS, Gabor; PROSZENYAK, Agnes; BALINT, Balazs; BRUNO, Alain; GENESTE, Olivier; DAVIDSON, James Edward Paul; MURRAY, James Brooke; CHEN, I-Jen; PERRON-SIERRA, Francoise; WO2015/97123; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6863-73-6, name is 3-Chloropyrazin-2-amine, 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. Quality Control of 3-Chloropyrazin-2-amine

Bromoacetaldehyde diethyl acetal (45 ml, 0.29 mol) was treated with water (33 ml) and 48% hydrobromic acid (33 ml) and this mixture was heated at 95C for 90 min. The reaction was cooled, diluted with propan-2-ol (300 ml) and treated with sodium hydrogencarbonate (33 g) added in portions. This mixture was stirred for 30 min then filtered. The filtrate was treated with 2-amino-3- chloropyrazine (25 g, 0.19 mol) and then heated at 90C for 16 h. The reaction was cooled to ambient temperature, concentrated to about one-third volume and then treated with 48% hydrobromic acid (25 ml). More propan-2-ol (300 ml) was added and the mixture aged for 1 h. The resulting solid was collected by filtration, washed with propan-2-ol and then dissolved in water (500 ml). This solution was made basic by adding solid sodium hydrogencarbonate and then extracted with chloroform (3 x 250 ml). The organics were combined, dried over anhydrous magnesium sulphate, filtered and concentrated to give a solid. Trituration with diethyl ether afforded 8-CHLOROIMIDAZO [1, 2-A] PYRAZINE as an off- white solid (18.6 g, 63%)

The synthetic route of 6863-73-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME LIMITED; WO2004/41826; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem