Pyrazines

Application of 143591-61-1, A common heterocyclic compound, 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, molecular formula is C6H3BrClN3, 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.

If one were to add 0.8 eq of benzylmagnesium bromide, in ether at -78C with 5% Palladium tetrakistriphenylphosphine under Nitrogen, to compound 161a then one would obtain compound 161b after workup using techniques known in the art.

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; SCHERING CORPORATION; WO2009/73777; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 5049-61-6,Some common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

Ethyl bromopyruvate (2.15 g, 11.04 mmol) was added to stirred solution of 2-aminopyrazine (1 g, 10.5 mmol) in 1,2-Dimethoxy ethane (10 mL). The reaction mixture was stirred at 20-35 C. for 2 h. The mixture was then filtered to obtain a solid precipitate which was dried well, dissolved in EtOH (10 mL) and refluxed for 2 h. This mixture was concentrated, diluted with aqueous saturated sodium bicarbonate solution, extracted with chloroform.-The chloroform layer was washed with water followed by brine solution, dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford the crude product, which was purified by column chromatography (using 60-120 silica gel and 60% EtOAc in Hexane as eluent) to afford 450 mg of the title compound. 1H NMR (400 MHz, CDCl3) delta ppm 9.22 (1H, s), 8.28 (1H, s), 8.12-8.08 (1H, m), 8 (1H, d, J=4.8 Hz), 4.52-4.47 (2H, m), 1.5 (3H, t).

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

Reference:
Patent; DR. REDDY’S LABORATORIES LTD.; Sasmal, Pradip Kumar; Ahmed, Shahadat; Prabhu, Ganesh; Tehim, Ashok; Paradkar, Vidyadhar; Dattatreya, Marahanakuli Prasanna; Mavinahalli, Nanjegowda Jagadeesh; US2015/5280; (2015); A1;,
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 19745-07-4 as follows. Recommanded Product: 19745-07-4

2.3 g of benzyl alcohol was added under ice-cooling to a mixture of 3.0 g of 2,5-dichloropyrazine, 880 mg of sodium hydride (60percent, oil) and 50 mL of NMP.The reaction mixture was warmed to room temperature and stirred at room temperature for 5 hours.Water was added to the obtained reaction mixture, and the mixture was extracted with ethyl acetate. The obtained organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure.The obtained residue was subjected to silica gel chromatography to obtain 3.1 g of Intermediate 1 represented by the following formula.

According to the analysis of related databases, 19745-07-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SUMITOMO CHEMICAL COMPANY LIMITED; NAKAJIMA, YUJI; (211 pag.)JP2017/114883; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 113305-94-5, name is 5-Aminopyrazine-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 113305-94-5, Application In Synthesis of 5-Aminopyrazine-2-carbonitrile

Methyl 4-((1-(tert-butoxycarbonyl)piperidin-4-yl)methylamino)-6-chloronicotinate (0.200 g, 0.52 mmol), 4-amino-cyanopyrazine (0.094 g, 0.78 mmol), cesium carbonate (0.340 g, 1.04 mmol), Pd2(dba)3 (0.021 g, 0.02 mmol) and xantphos (0.024 g, 0.04 mmol) were mixed under an argon atmosphere before the addition of toluene (3 ml_). The reaction mixture was heated at 130C for 30 minutes by microwave irradiation. The cooled mixture was dissolved in methanol – dichloromethane (1 : 1 ). The mixture was purified by ion exchange chromatography on SCX-II acidic resin (2g) eluting with methanol, then 2M ammonia-methanol. The basic fractions were combined and evaporated. Flash column chromatography eluting with ethyl acetate – hexane (1 : 3) gave methyl 4-((1-(terf- butoxycarbonyl)piperidin-4-yl)methylamino)-6-(5-cyanopyrazin-2-ylamino)nicotinate as a yellow solid (0.090 g, 37%).1H NMR (500 MHz, CDCI3) delta 1.19-1.28 (2H, m), 1.41 (9H, s), 1.79-1.82 (2H, m), 1.91- 1.97 (1H, m), 2.70-2.80 (3H, m), 3.25 (2H, t, J = 6.3 Hz), 3.86 (3H, s), 4.12-4.14 (2H, m), 6.53 (1 H, s), 7.28 (1 H, s), 8.23 (1 H, t, J = 5.3 Hz), 8.62 (1 H, s), 8.66 (1 H, d, J = 1.2 Hz), 9.16 (1H, d, J = 1.2 Hz) 9.58(1 H, s). LCMS (3) Rt 4.37 min; m/z (ESI+) 468 (MH+).

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Patent; CANCER RESEARCH TECHNOLOGY LIMITED; WO2009/44162; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 33332-29-5, name is 2-Amino-5-chloropyrazine, molecular formula is C4H4ClN3, 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. SDS of cas: 33332-29-5

General procedure: Method B is a modification of Method A and was performed under nitrogen atmosphere andwith extended work-up. Substituted benzoyl chloride (1.5 mmol, 1.2 equiv) was placed into the askunder nitrogen, diluted with dry DCM (5 mL) and dry pyridine (400 mg, 5 mmol, 4 equiv) was added.The mixture was mixed for 5 min under nitrogen. Then, 5-chloropyrazin-2-amine (162 mg, 1.25 mmol,1 equiv) dissolved in DCM (10 mL) was added dropwise over 10 min under nitrogen ow. The askwas closed by septum and stirred for additional 6 h. After reaction, the mixture was diluted with DCMto the final volume of 40 mL and washed with water (1 30 mL), 5% (m/m) aqueous NaHCO3 solution(1 30 mL), and brine (1 30 mL). The organic layer was dried over anhydrous Na2SO4 and adsorbedon silica (4 g) by evaporating the solvents under reduced pressure. Automated flash chromatographywas run using same conditions as described in Method A. If needed, the products were recrystallizedfrom hot EtOH (crystallization initiated by cooling and dropwise addition of cold water).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 33332-29-5, its application will become more common.

Reference:
Article; Zitko, Jan; Mindlova, Al?b?ta; Vala?ek, Ond?ej; Jand’ourek, Ond?ej; Paterova, Pavla; Janou?ek, Ji?i; Kone?na, Klara; Dole?al, Martin; Molecules; vol. 23; 9; (2018);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 117103-53-4,Some common heterocyclic compound, 117103-53-4, name is 2-Bromo-5-nitropyrazine, molecular formula is C4H2BrN3O2, 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.

Step 1. Preparation of Dimethyl-[2-(5-nitro-pyrazin-2-yloxy)-ethyl]-amine To a 100 ml dried round bottom flask was added bromonitropyrazine (300 mg, 1.47 mmol, Eq: 1.00) and CH3CN (10 ml). To the mixture was added K2CO3 (203 mg, 1.47 mmol, Eq: 1.00) under argon to afford a light yellow slurry. To the slurry was added N,N-dimethylaminothanol (131 mg, 148 mul, 1.47 mmol, Eq: 1.00) dropwise. The reaction became an orange slurry and was stirred at room temperature overnight. The reaction mixture was filtered and the filter cake was washed with CH3CN (3*20 mL). The combined filtrate and washes were concentrated in vacuo and purified by column chromatography eluting with 5-10% (10% NH4OH in MeOH) in 1/1 EtOAc/Hex eluent to afford 270 mg (87%) of the title compound.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Bromo-5-nitropyrazine, its application will become more common.

Reference:
Patent; Berthel, Steven Joseph; Billedeau, Roland Joseph; Brotherton-Pleiss, Christine E.; Firooznia, Fariborz; Gabriel, Stephen Deems; Han, Xiaochun; Hilgenkamp, Ramona; Jaime-Figueroa, Saul; Kocer, Buelent; Lopez-Tapia, Francisco Javier; Lou, Yan; Orzechowski, Lucja; Owens, Timothy D.; Tan, Jenny; Wovkulich, Peter Michael; US2012/40949; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 32111-21-0, 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. 32111-21-0, name is 2-Iodopyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

4.4 ml of tetrabutylammonium fluoride (1M solution in THF) are added to a solution of 450 mg (2.18 mmol) of iodopyrazine, 647 mg (3.28 mmol) of 5-chloro-3-methoxy-2-(prop-2-ynyloxy)-pyridine (Example P7), 83 mg (0.44 mmol) of copper(l) iodide and 153 mg (0.22 mmol) of bis(triphenylphosphine)palladium dichloride (Pd(PPh3)2CI2) in 14 ml of dioxane. The reaction mixture is stirred for 3 hours at 50C under an argon atmosphere and is then allowed to cool to 20C. The solvent is removed under reduced pressure and the crude product obtained is purified by means of flash chromatography (eluant: ethyl acetate/petroleum ether 1/2). The desired title compound is obtained as a brown solid having a melting point of 142C in a yield of 510 mg (84 % of theory). Rf = 0.50 in ethyl acetate/petroleum ether 1/1;1H NMR (CDCI3): delta(ppm)= 3.89 (s, 3H); 5.29 (s, 2H); 7.08 (d, J=2.2 Hz, 1H); 7.71 (d, J=2.2 Hz, 1H); 8.48 (d, J=2.5 Hz, 1H); 8.52 (dxd, J=1.3 and 2.5 Hz, 1H); 8.66 (d, J=1.3 Hz, 1H).

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-Iodopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; SYNGENTA PARTICIPATIONS AG; WO2003/104206; (2003); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 5049-61-6, These common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, 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 solution of aminopyrazine (P) (1.902 g, 20 mmol, 1 eq.) in chloroform (160 ml) was added pyridine (3.4 ml, 42 mmol, 2.1 eq.) and bromine (2.15 ml, 2.1 eq.). The mixture was stirred at rt for 2 hours. The mixture was then diluted with DCM, washed with water, dried over sodium sulfate and concentrated to afford 2.583 g of title compound (yield 51%) as a light brown solid. 1H-NMR (400 MHz, DMSO-d6) delta 8.12 (s, 1H), 6.98 (br s, 2H).

The synthetic route of 5049-61-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Sugen, Inc.; US2004/220189; (2004); 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below., Formula: C4H3Br2N3

(a)To a 100 mL autoclave was added 2-amino-3,5-dibromopyrazine (10 g, 39.54 mmol, 1 eq) and aqueous ammonia (50 mL, commercially available).The temperature was raised to 130 C under nitrogen atmosphere to carry out the reaction overnight (10 to 12 hours); the temperature was lowered, suction filtration, and the obtained solid was vacuum dried to obtain 5.0 g of compound II.

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

Reference:
Patent; Suzhou Derivative Biological Technology Co., Ltd.; Liu Ke; (7 pag.)CN108707150; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 59489-71-3, A common heterocyclic compound, 59489-71-3, name is 2-Amino-5-bromopyrazine, molecular formula is C4H4BrN3, 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 2; 5-bromopyrazine-2-carbonitrile; i) Tetrakis (triphenyl phosphine) palladium(0) (10 mg) was added to a mixture of 5-bromopyrazin-2-amine (0.575 mmol), potassium cyanide (1.15 mmol), copper (I) iodide (0.575 mmol) and 18-crown-6 (20 mg) in dry DMF (1 mL) in a screw top reaction vessel under nitrogen atmosphere, and the mixture was heated with stirring at 200 C. for 1 h. After cooling, water (5 mL) was added and the product was extracted with chloroform (2¡Á) to give 5-aminopyrazine-2-carbonitrile after purification by chromatography (silica, hexane:ethyl acetate) (0.208 mmol, 36%).

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; NPS PHARMACEUTICALS, INC.; US2007/37820; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem