Month: May 2021

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. 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. SDS of cas: 36070-80-1

5-chloropyrazine-2-carboxylic acid (1.00 g, 6.31 mmol),2,2,2-Trifluoroethylamine (687.52 mg, 6.94 mmol),N, N-diisopropylethylamine (3.56 mL, 20.81 mmol),Dissolve O- (7-azabenzotriazol-1-yl) -N, N, N ‘, N’-tetramethyluronium hexafluorophosphate in methylene chloride (30 mL) and stir at room temperature overnight under a nitrogen atmosphere did.Thereafter, saturated aqueous sodium bicarbonate solution was added, extraction was performed with ethyl acetate, and magnesium sulfate was added for dehydration.The magnesium sulfide was removed by suction filtration, the solution was concentrated under reduced pressure, and the composition was purified by silica gel chromatography to give the title compound.(1.10 g, 72.8% yield, white solid)

The synthetic route of 36070-80-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Nippon Kayaku Co.,Ltd.; Hasegawa, Shinji; Ueno, Shotaro; Shinko, Daiki; Kobayashi, Takehiko; Miyake, Takaaki; Asano, Shu; Sumi, Takuto; (101 pag.)JP2019/19124; (2019); A;,
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. 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., Recommanded Product: 875781-43-4

General procedure: 2-Bromo-5H-pyrrolo[3,2-b]pyrazine(4; 0.471 g,2.39 mmol), 4-pyridylboronic acid (0.58 g, 4.72 mmol), dichloro 1,1′-bis(diphenylphosphino)ferrocenepalladium (II) dichloromethane adduct (0.097 g, 0.12 mmol), acetonitrile(3 mL) and 1M sodium carbonate (3 mL) were placed in a 10 mL CEM microwavevial. The vial was capped and irradiated in a CEM microwave reactor for 30minutes at 150 C.Water (3 mL) and ethyl acetate (9 mL) were added the layers were partitioned. Theaqueous layer was extracted with ethyl acetate (2 x 10 mL). The combined organicextracts were washed with saturated sodium chloride (5 mL), dried over MgSO4and concentrated under reduced pressure. The residue was purified by preparativereverse phase HPLC to give 2-(pyridin-4-yl)-5H-pyrrolo[2,3-b]pyrazine(14; 0.28 g,60%) as an off white solid: 1H NMR (400 MHz, DMSO-d6) delta 12.24 (s, 1H), 9.00(s, 1H), 8.69 (dd, J = 4.5, 1.6 Hz, 2H), 8.12 (dd, J = 4.5, 1.6Hz, 2H), 7.98 (d, J = 3.6 Hz, 1H), 6.74 (d, J = 3.6 Hz, 1H); ESMSm/z 197.1 (M+1).

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:
Article; Burdick, Daniel J.; Wang, Shumei; Heise, Christopher; Pan, Borlan; Drummond, Jake; Yin, Jianping; Goeser, Lauren; Magnuson, Steven; Blaney, Jeff; Moffat, John; Wang, Weiru; Chen, Huifen; Bioorganic and Medicinal Chemistry Letters; vol. 25; 21; (2015); p. 4728 – 4732;,
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. name: 3,5-Dibromo-1-methylpyrazin-2(1H)-one

Example 185a 5-Bromo-3-(imidazo[1,2-a]pyridin-7-ylamino)-1-methylpyrazin-2(1H)-one 185a A 100-mL round-bottomed flask equipped with a reflux condenser was charged with imidazo[1,2-a]pyridin-7-amine (665 mg, 5.0 mmol), Cs2CO3 (3.26 g, 10 mmol), 3,5-dibromo-1-methylpyrazin-2(1H)-one (1.86 g, 7.0 mmol), Xantphos (289 mg, 0.50 mmol), Pd2(dba)3 (458 mg, 0.50 mmol), and 1, 4-dioxane (30 mL). After bubbling nitrogen through the mixture for 30 minutes, it was heated at 100°C under nitrogen atmosphere for 16 h. Analysis of the reaction mixture by LCMS showed little starting material remained. The reaction mixture was cooled to room temperature and filtered. The filtrate was diluted with dichloromethane (60 mL) and water (50 mL). The aqueous layer was separated and extracted with dichloromethane (3 * 20 mL). The combined organic layers was dried over Na2SO4, filtered, and concentrated under reduced pressure. The dark residue was purified by silica-gel column chromatography eluting with dichloromethane/methanol (60/1 to 30/1) to afford 185a (700 mg, 44percent) as a light yellow solid. MS-ESI: [M+H]+ 320

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

Reference:
Patent; F.Hoffmann-La Roche AG; CRAWFORD, James John; ORTWINE, Daniel Fred; WEI, BinQing; YOUNG, Wendy B.; EP2773638; (2015); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

33332-28-4, name is 2-Amino-6-chloropyrazine, 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. COA of Formula: C4H4ClN3

Example 1C 6-(3-butenyloxy)-2-pyrazinamine A suspension of NaH (60percent, 618 mg, 15.45 mmol) in dioxane (30 mL) at 0° C. was treated with 3-buten-1-ol (1.33 mL, 15.45 mmol), stirred for 2 hours, treated with 2-amino-6-chloropyrazine (1 g, 7.72 mmol), stirred at 100° C. for 2.5 days, cooled to room temperature, and diluted with ethyl acetate. The mixture was washed with water, dried (MgSO4), filtered, and concentrated. The concentrate was purified by flash column chromatography eluding with hexanes/ethyl acetate (2:1) to provide the desired product (390 mg, 31percent). MS (DCI/NH3) m/z 166.12 (M+H)+; 1H NMR (500 MHz, benzene-d6) delta 2.66 (m, 2H), 4.42 (t, J=6.87 Hz, 2H), 5.24 (dd, J=10.22, 1.98 Hz, 1H), 5.30 (m, 1H), 6.04 (m, 1H), 7.64 (s, 1H), 7.65 (s, 1H).

The synthetic route of 33332-28-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Lin, Nan-Horng; Li, Gaoquan; Przytulinska, Magdalenna K.; Sowin, Thomas J.; Sullivan, Gerard M.; Tao, Zhi-Fu; Tong, Yunsong; Wang, Le; US2005/215556; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 5521-55-1, 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. 5521-55-1 name is 5-Methylpyrazine-2-carboxylic acid, 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.

To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added 5-methylpyrazine-2-carboxylic acid (1.0 eq), tert-butanol (3.5 vols) and di-isopropylethylamine (1.5 eq) under a nitrogen atmosphere. The mixture was heated to 82 C., then diphenylphosphorylazide (1.0 eq) was added over a time period of 5-14 hours, maintaining the temperature of the reaction mixture at approximately 82 C. The reaction mixture was stirred for at least 1.5 hours, and then cooled to approximately 60 C. A solution of 4% w/w sodium hydroxide (1.75 eq) was added over a period of 2 hours. The mixture was cooled to 15 C. over at least 5 hours then held at 15 C. for 3 hours. The batch was then filtered, and the solid slurry washed with water (2 vols). The batch was again slurry washed with water (2 vols). After drying at 55-60 C. overnight, the desired product was obtained as a solid (corrected yield 56-63%). 1H NMR delta (400 MHz CDCl3): 9.18 (s, 1H), 8.17 (bs, 1H), 8.11 (s, 1H), 2.51 (s, 3H), 1.56 (s, 9H)

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

Reference:
Patent; AstraZeneca AB; US2010/210841; (2010); 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. 33332-28-4, name is 2-Amino-6-chloropyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2-Amino-6-chloropyrazine

2,2,2-Trifluoroethylisothiocyanate (6 ml.) was added to 2-amino-6-chloropyrazine (6 g.) in acetonitrile (50 ml.) and the mixture heated under reflux on the steam bath for 6 hours. On cooling the precipitated solid was recrystallized from toluene to give 2-chloro-6-(3-[2,2,2-trifluoroethyl]thioureido)pyrazine, m.p. 170°-172°.

The synthetic route of 33332-28-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Imperial Chemical Industries PLC; US4451463; (1984); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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 622392-04-5 as follows. name: 2-Bromo-5-iodopyrazine

EXAMPLE 41C (endo)-3-(5-Iodo-pyrazin-2-yloxy)-8-methyl-8-aza-bicyclo[3.2.1]octane Under N2, the mixture of (endo)-tropine (Aldrich, 1.54 g, 11 mmol) was treated with potassium t-butoxide (Aldrich, 0.96 g, 10 mmol) in THF (anhydrous, Aldrich, 50 mL) at ambient temperature for 1 h. The product of Example 41B (2.85 g, 10.0 mmol) and was added. The brown mixture was stirred at ambient temperature for 4 hours and quenched with water (5 mL). The mixture was concentrated and the residue was purified by chromatography (150 g SiO2, EtOAc:MeOH:NH3.H2O, 90:10:1, Rf. 0.20) to give the title compound. 1H NMR (300 MHz, CD3OD) delta 2.16-2.60 (m, 8H), 2.84 (s, 3H), 3.78-4.05 (m, 2H), 5.17-5.40 (m, 1H), 8.14 (d, J=1.36 Hz, 1H), 8.42 (d, J=1.36 Hz, 1H) ppm; MS (DCI/NH3) m/z 346 (M+H)+.

According to the analysis of related databases, 622392-04-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Ji, Jianguo; Li, Tao; Lynch, Christopher L.; Gopalakrishnan, Murali; US2008/45539; (2008); 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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Formula: C6H7N3O2

Hydrazine monohydrate (34 mL, 1094.95 mmol) was added portionwise to a stirred suspension of methyl 3-aminopyrazine-2-carboxylate (21.3 g, 139.09 mmol) in ethanol (65 mL) at r.t. The resulting slurry was stirred at 60 °C for 2 hours, cooled to room temperature and filtered. The solid was washed with cold ethanol (2 x 25 ml) and dried to a constant weight to afford 3-aminopyrazine-2-carbohydrazide (20.75 g, 97 percent) as a beige solid: 1H NMR Spectrum: (DMSO-d6) 4.49 (2H, d), 7.46 (2H, br s,), 7.78 (IH, d), 8.17 (IH, d), 9.79 (IH, t); Mass Spectrum [M+H]+ = 154.

The synthetic route of 16298-03-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; BARLAAM, Bernard Christophe; BERRY, David; DELOUVRIE, Benedicte; HARRIS, Craig Steven; LAMBERT-VAN DER BREMPT, Christine Marie Paul; OUVRY, Gilles; REID, Gary Patrick; TOMKINSON, Gary Peter; WO2014/114928; (2014); 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, COA of Formula: C5H2ClN3

To a microwave vial was added (2S,3R,4R)-ethyl 1-acetyl-4-amino-2,3-dimethyl-1,2,3,4-tetrahydroquinoline-6-carboxylate (for a preparation see Intermediate 4, 200 mg, 0.689 mmol) and 5-chloropyrazine-2-carbonitrile (192 mg, 1.378 mmol). DMSO (1 mL) was added, followed by DIPEA (0.361 mL, 2.066 mmol) and the microwave vial sealed and heated to 160 C for 30 min in a microwave reactor. H20 (20 mL) was added, followed by Et20 (20 mL) and the layers separated. The aqueous layer was further extracted with Et20 (2 x 20 mL) and the combined organics then back extracted with brine (2 x 20 mL). The combined organics were then dried (Na2S04) and concentrated in vacuo to afford a brown oil. This was loaded in DCM and purified by column chromatography (25 g silica) using a gradient of 0-60% EtOAc / cyclohexane. The appropriate fractions were collected and concentrated in vacuo to afford the product as a brown oil (268 mg). LCMS (2 min Formic): Rt = 1.01 min, [MH]+ = 394.

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, 5-Chloropyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO.2) LIMITED; ATKINSON, Stephen, John; HIRST, David, Jonathan; HUMPHREYS, Philip, G.; LINDON, Matthew, J.; PRESTON, Alexander, G.; SEAL, Jonathan, Thomas; WELLAWAY, Christopher, Roland; (66 pag.)WO2016/38120; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 21279-64-1, name is 5-Chloropyrazine-2-carboxamide, 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. Product Details of 21279-64-1

General procedure: 150 mg (0.952 mmol) of 5-Cl-PZA (1) or 6-Cl-PZA (2) was dissolved in ethanol together with triethylamine (1 eq., 96 mg, 0.952 mmol). Three equivalents of corresponding alkylamine were added to the reaction mixture and refluxed in ethanol generally for 6 hours. The completion of the reaction was checked by TLC chromatography (eluent: hexane/ethyl acetate, 1:2). The crude product was absorbed on silica by solvent evaporation and purified by flash chromatography (hexane/ethyl acetate gradient elution).

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

Reference:
Article; Servusova, Barbora; Paterova, Pavla; Mandikova, Jana; Kubicek, Vladimir; Kucera, Radim; Kunes, Jiri; Dolezal, Martin; Zitko, Jan; Bioorganic and Medicinal Chemistry Letters; vol. 24; 2; (2014); p. 450 – 453;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem