Tag: M.W=100-200

Some common heterocyclic compound, 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, molecular formula is C6H7N3O2, 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. name: Methyl 2-aminopyrazine-3-carboxylate

3-Aminopyrazine-2-carboxylic acid methyl ester (0.8 g, 5.2 mmol) and 3-bromopyridine (1.2 g, 7.8 mmol) were dissolved in 20 mL dry toluene. 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (0.6 g, 1.04 mmol), sodium tert.-butylate (0.75 g, 7.8 mmol) and tri(dibenzylideneacetone)dipalladium chloroform complex (0.54 g, 0.52 mmol) were added and the reaction mixture was stirred under microwave irradiation for 60 minutes at 150° C. The reaction mixture was then evaporated and purified by flash chromatography on silica gel (heptane/ethyl acetate 1:2->0:100 gradient). The desired product was obtained as a brown solid (260 mg, 22percent), MS: m/e=231.1 (M+H+).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 16298-03-6, its application will become more common.

Reference:
Patent; Jaeschke, Georg; Kolczewski, Sabine; Porter, Richard Hugh Philip; Vieira, Eric; US2006/199828; (2006); A1;,
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22047-25-2, name is Acetylpyrazine, 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. Computed Properties of C6H6N2O

General procedure: A 100 mL round-bottom flask charged with 2-acetylpyrazine (1.47 g, 2 mmol) was added MeOH (30 mL), KOH pellets (0.675 g,2 mmol) and water (2 mL). The resulting mixture was stirred for10 min and then added corresponding n,n?-dimethoxybenzaldehydes (1.0 g, 1 mmol) and ammonium solution (6 mL) was added slowly stirring at room temperature for 4 h, a white precipitate obtained was filtered, washed with MeOH and diethyl ether. The crude products on recrystallization in a mixture of CHCl3:MeOH (1:1) gave white crystals of desired compounds, 1-4.

The synthetic route of 22047-25-2 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Golla, Ramesh; Kumar, P. Raghavendra; Suchethan; Foro, Sabine; Nagaraju; Journal of Molecular Structure; vol. 1201; (2020);,
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38557-72-1, 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. 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, A new synthetic method of this compound is introduced below.

Step 1: Synthesis of 3,5-Dimethyl-2-(dibenzofuran-4-yl)pyrazine (abbreviation: Hdm4 dbfpr) First, into a recovery flask equipped with a reflux pipe were placed 1.51 g of 2-chloro-3,5-dimethylpyrazine, 2.25 g of 4-dibenzofuranylboronic acid, 1.12 g of sodium carbonate, 0.048 g of bis(triphenylphosphine)palladium(II) dichloride (abbreviation: Pd(PPh3)2Cl2), 15 mL of water, and 15 mL of acetonitrile, and the air inside the flask was replaced with argon. Heating was performed by microwave irradiation (2.45 GHz, 100 W) of this reaction container for 10 minutes, so that reaction occurred. After that, water was added to this reaction solution, and extraction with dichloromethane was carried out. A solution of the obtained extract was washed with water and dried over magnesium sulfate. After the drying, the solution was filtered. After the solvent of this solution was distilled, the obtained residue was washed with methanol, so that the pyrazine derivative which was the object of the synthesis, Hdm4 dbfpr, was obtained (a pale orange powder in a yield of 65%). Note that a microwave synthesis system (Discover, produced by CEM Corporation) was used for the microwave irradiation. The synthesis scheme of Step 1 is illustrated in the following scheme (x-1).

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Reference:
Patent; Semiconductor Energy Laboratory Co., Ltd.; US2012/104373; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 63286-28-2,Some common heterocyclic compound, 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, molecular formula is C4H5ClN4, 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.

-Chloro-3-hydrazinylpyrazine (440 g, 3.0 mol) was suspended in acetic acid (500 mL) and cooled to lOoC. A solution of sodium nitrite (220 g, 3.2 mol) in water (200 mL) at 10 C was added. The resulting mixture was stirred at 10 C for 1 h, during which time a crystalline solid precipitated. The precipitate was collected by filtration, washed with ethanol (200 mL) and dried to afford the desired product as a red solid (350 g, 73% yield).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Chloro-3-hydrazinylpyrazine, its application will become more common.

Reference:
Patent; KALYPSYS, INC.; CHEN, Pingyun; CARINO, Stephen, A., R.; COUCH, Ricky, W.; KINDER, Daniel, S.; NORTON, Beth, A.; WO2013/39785; (2013); A2;,
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Application of 21279-62-9,Some common heterocyclic compound, 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, molecular formula is C5H4ClN3O, 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: Compounds 1-6 were prepared according to conventional organic synthesis methods. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was dissolved in THF (20 mL) in a round bottom flask and after that treated with two equivalents of the corresponding benzylamine and an equimolar amount of triethylamine. The reaction was conducted with continuous stirring and heating (70 C) under reflux in an oil bath for 15 h. Compounds 7-15 were synthesised using a microwave reactor with a focused field. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was put into a thick-walled tube together with the corresponding benzylamine (2.54 mmol), pyridine (1.27 mmol), methanol (approx. 5 mL) and a magnetic stir bar and then sealed with a special cap. The reaction parameters were set according to the previously published paper as follows-140 C, 30 min, 200 W [29]. Reaction progress was checked by TLC (hexane:ethyl acetate-1:1). Regardless of the synthesis method used,all reaction mixtures were adsorbed on silica and subjected to preparative flash chromatography (hexane and ethyl acetate, gradient elution, detection wavelengths 260 nm and 280 nm). Products were recrystallized from ethanol or ethanol and water if necessary. All final substances were chemically characterized (1H-NMR, 13C-NMR, IR, melting point and elemental analysis).

The synthetic route of 21279-62-9 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Jandourek, Ondrej; Tauchman, Marek; Paterova, Pavla; Konecna, Klara; Navratilova, Lucie; Kubicek, Vladimir; Holas, Ondrej; Zitko, Jan; Dolezal, Martin; Molecules; vol. 22; 2; (2017);,
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Synthetic Route of 22047-25-2,Some common heterocyclic compound, 22047-25-2, name is Acetylpyrazine, molecular formula is C6H6N2O, 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.

Preparation 4; 1-Pyrazin-2-yl-ethylamine; The synthetic procedure used in this preparation is outlined below in Scheme F. To a solution of 1-pyrazin-2-yl-ethanone (2.0 g, 15.85 mmol) and ammonium acetate (19.337 g, 158.5 mmol) in methanol (50 mL) was added sodium cyanoborohydride (0.7 g, 11.1 mmol) in one portion. The reaction mixture was stirred overnight at room temperature. After removal of methanol, water (20 mL) was added to the residue and the resulting solution was basified by addition of sodium hydroxide to pH=13. The aqueous solution was extracted with dicholromethane and the combined organic phase was dried over sodium sulfate. Removal of the solvent under reduced pressure afforded 14.62 g of 1-pyrazin-2-yl-ethylamine, yield: 75%. MS (M+H)=124.

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

Reference:
Patent; Roche Palo Alto LLC; US2009/163499; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 13134-38-8, 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. 13134-38-8, name is 3,6-Dimethylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

e) Ethyl-N-[(3,6-dimethylpyrazin-2-yl)carbamothioyl]carbamate To a solution of 3, 6-dimethyl-pyrazin-2-ylamine (5 g, 40.65 mmol) in dioxane (150ml) was added ethoxycarbonyl isothiocyanate (4.75 ml, 40.65 mmol) at 25 C, and the reaction mixture was stirred for 18 hours at 25 C. Volatiles were removed in vacuo. The resultant residue was dissolved in ethyl acetate, washed with water twice, and brine, dried over anhydrous sodium sulfate, filtered, and evaporated affording ethyl-N-[(3,6-dimethylpyrazin-2- yl)carbamothioyl] carbamate (10 g, 96.73%) as a light yellow solid. MS: m/z= 255 (M+H+)

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, 3,6-Dimethylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; HOFFMANN-LA ROCHE INC.; FLOHR, Alexander; GROEBKE ZBINDEN, Katrin; KUHN, Bernd; LERNER, Christian; RUDOLPH, Markus; SCHAFFHAUSER, Herve; WO2013/178572; (2013); A1;,
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Some common heterocyclic compound, 41110-29-6, name is Methyl 3-methylpyrazine-2-carboxylate, molecular formula is C7H8N2O2, 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. COA of Formula: C7H8N2O2

In a 1-L flask, the methyl 3-methylpyrazine-2-carboxylate (step 1, 16.08 g, 106 mmol) was suspended in CHCl3 (300 mL). 3-chlorobenzoperoxoic acid (Aldrich, 24.62 g, 143 mmol) was added. The reaction mixture was heated to 70 C. for 16 h. The reaction mixture was quenched with saturated NaHCO3 (200 mL). The layers were separated, and the aqueous layer was further extracted with DCM (2×100 mL). The combined organic layers were dried over MgSO4, and the filtrate was concentrated to afford the title compound. MS m/z=169 (M+H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 41110-29-6, its application will become more common.

Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); A1;,
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Application of 77112-53-9, The chemical industry reduces the impact on the environment during synthesis 77112-53-9, name is Imidazo[1,2-a]pyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

General procedure: Imidazo[1,2-a]pyrazine-2-carboxylic acid (5) (1.0 equiv.) Mukaiyama?s reagent and 2-chloro-1-methylpyridinium iodide (1.2 equiv.) were suspended in DMF (5.0 mL) under nitrogen atmosphere. Into the reaction mixture, aliphatic/aromatic amines (6a-l) (1.0 equiv.) and 1-methylimidazole (2.0 equiv.) were added. A homogeneous solution was formed after a gentle stirring. The reaction mixture was sealed in a microwave glass reactor and then irradiated by microwave oven at a constant temperature of 80 C with continuous stirring (1 min ramp, 15 min reaction time). After the reaction was completed, the solvent was removed through a rotary evaporator and the resulting residue was extracted by a biphasic system of 45 mL diethyl ether and 45 mL water. After the layer separation, the ether layer was dried by anhydrous sodium sulphate, followed by an evaporation of ether to get compounds 7a-l (Scheme-I).

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, Imidazo[1,2-a]pyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Jyothi, Boggavarapu; Madhavi, Nannapaneni; Asian Journal of Chemistry; vol. 32; 1; (2020); p. 84 – 90;,
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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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 33332-25-1

Intermediate 33: 5-Chloropyrazine-2-carboxylic acid To a solution of methyl-5-chloropyrazine-2-carboxylate (120 mg, 0.70 mmol) in a mixture of acetonitrile (2 mL) and DMF (1 mL) was added lithium chloride (295 mg, 6.95 mmol). The suspension was heated to 160 C. for 5 minutes in a microwave after which time the reaction was diluted with water (10 mL). Saturated sodium bicarbonate solution (20 mL) was added and the aqueous layered extracted with ethyl acetate (2*30 mL). The organic extracts were discarded and the aqueous layer adjusted to pH 4 with 1N hydrochloric acid. The aqueous phase was extracted twice with ethyl acetate (20 mL) and the combined organics washed with water (2*20 mL) and brine (10 mL) and dried (MgSO4). The volatiles were removed under reduced pressure to afford the product (68 mg). 1H NMR delta (400 MHZ, CDCl3): 7.20 (1H, br s), 8.72 (1H, s), 9.21-9.21 (1H, m); m/z 157 (M-H)+.

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AstraZeneca AB; US2008/171734; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem