Category: Pyrazines

Electric Literature of 77112-52-8, These common heterocyclic compound, 77112-52-8, name is Ethyl imidazo[1,2-a]pyrazine-2-carboxylate, 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.

10% Pd/C (40 mg) was added to a solution of ethyl imidazo[1,2-a]pyrazine-2-carboxylate (410 mg, 2.15 mmol) and conc.HCl (0.5 mL) in EtOH (9.5 mL) and stirring was continued under a hydrogen atmosphere for 16 h. The reaction mixture was filtered over a celite bed and the filtrate was concentrated under reduced pressure to afford the crude product, which was purified by washing with diethyl ether and dried to afford 400 mg of the title compound as a yellow hygroscopic solid. MS (ESI): m/z 196 (M+H).

The synthetic route of 77112-52-8 has been constantly updated, and we look forward to future research findings.

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

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. 123-32-0, name is 2,5-Dimethylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C6H8N2

1), in 125 ml in the reaction bottle, by adding 1.08g (10mmol) 2, 5-dimethyl-pyrazine, 1.13g (4mol) FeSO4· 7H2O, by adding 30 ml of water (i.e., 3 ml/1mmol), stirring in the ice bath, then measure 0.1mol (6 ml) 98% concentrated sulfuric acid to constant pressure dropping funnel slowly dropping, the temperature change in the process of dropping the attention, to maintain the temperature of the reaction bottle too high (i.e., to control the temperature to 60 C the following can be). After concentrated sulfuric acid instillment , on a rectifier 22mmol (7.5 ml) hydrogen peroxide, PV drop instillment , and to continue the reaction in the ice bath, dripping at any time in the process of observing reaction bottle temperature change (i.e., to control the temperature to 60 C the following can be). After dripping adding 240uL (3mmol) is propionaldehyde, slowly elevated temperature so as to control the temperature to 50-60C, in the reaction 1h, 2h, 3h, 4h are respectively adding 240uL is propionaldehyde. In the reaction process and reaction conditions for TLC, reaction conditions estimated raw material, when the raw material after the reaction is complete can stop the reaction (about 6h).2), stop heating after the reaction, cooling to room temperature, with 30 ml ethyl acetate extraction, the aqueous phase (the lower) the quality of the diluted for the fraction of 20% NaOH to adjust the pH to 8, in the process the alkali adjusting full stirring, not to allow the temperature of the solution is too high (i.e., not to exceed 60 C). Then extracting with ethyl acetate three times, combined with the phase (the upper), pressure-reducing (pressure -0.08–0.10 MPa) concentrated to dry, yellow oily substance is about 1.532 g. Finally through the column chromatography the 2-ethyl -3, 6-dimethyl-pyrazine separated.As follows:The silica gel chromatography (built-in 200-300 purpose silica gel 30g), the resulting 1.532g for column chromatography yellow oily substance; for the mobile phase ethyl acetate: petroleum ether = 1:20 of the mixed solution, the total consumption of mobile phase about 500 ml; final 1.245g product—2-ethyl -3, 6-dimethyl-pyrazine (the purity is 95.6%). Yield 90.88%.

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 123-32-0.

Reference:
Patent; Zhejiang University; Cheng, Jingli; Wang, Likun; Zhao, Yang; Zhao, Jinhao; (9 pag.)CN105237486; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 768-05-8,Some common heterocyclic compound, 768-05-8, name is Pyrazinoic acid hydrazide, molecular formula is C5H6N4O, 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.

2-Hydroxyacetophenone (0.1g; 0.73mmol), hydrazide 3c (0.1g; 0.73mmol) and acetic acid (0.20mL) were dissolved in methanol (5mL) and heated at 110C in an autoclave for 24h. After cooling to rt, the solid was filtered off, washed with methanol and dried over P2O5. The filtrate was diluted with water and left to crystallize at 4C for 24h. A second load of solid was filtered off, washed with water and methanol and dried over P2O5. The overall yield of yellow solid was 0.14g (74%; lit [37]. 63%). Rf=0.88 (CHCl3/MeOH 20:1). mp 237-239C. IR (KBr): numax, 3347; 1690; 1508; 1489; 1250; 1157; 1043; 1021cm-1. 1H NMR (300MHz, DMSO) delta 13.03 (s, 1H, OH), 11.53 (s, 1H, NH), 9.25 (s, 1H, Ar), 8.96-8.87 (m, 1H, Ar), 8.84-8.68 (m, 1H, Ar), 7.64 (dd, J=8.1, 1.5Hz, 1H, Ar), 7.43-7,16 (m, 1H, Ar), 7.02-6.73 (m, 2H, Ar), 2.46 (s, 3H, CH3). 13C NMR (75MHz, DMSO): delta 160.9, 160.4, 159.2, 148.5, 144.7, 144.6, 144.0, 132.2, 129.3, 119.6, 119.2, 117.8, 14.4. Anal. Calcd. for C13H12N4O2: C, 60.93; H, 4.72; N, 21.86; Found: C, 61.27; H, 4.83; N, 21.76.

The synthetic route of 768-05-8 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Hru?kova, Kate?ina; Pot??kova, Eli?ka; Hergeselova, Tereza; Liptakova, Lucie; Ha?kova, Pavlina; Mingas, Panagiotis; Kova?ikova, Petra; ?im?nek, Toma?; Vavrova, Kate?ina; European Journal of Medicinal Chemistry; vol. 120; (2016); p. 97 – 110;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 870787-06-7, name is 3-(Trifluoromethyl)pyrazine-2-carboxylic acid, 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 870787-06-7, Safety of 3-(Trifluoromethyl)pyrazine-2-carboxylic acid

Diphenylphosphoryl azide (3.47g, 12.6mmol) was added to a stirred solution of 3- trifluoromethylpyrazine-2-carboxylic acid (1 .92g, 9.7Ommol) and triethylamine (1 .28g, 12.6mmol) in tert-butanol (9.6m1, lOOmmol) and toluene (19.2m1). The resulting mixturewas heated at 90C for 4 hours and then allowed to cool. It was washed with 2M aqueous sodium bicarbonate, then dried through a phase-separation filter and concentrated under reduced pressure. The residue was purified by chromatography on silica gel using a gradient of ethyl acetate in hexane as eluent to give tert-butyl N-(3-trifluoromethylpyrazin- 2-yl)-carbamate containing 3-trifluoromethyl-2-aminopyrazine (2.Og) as a colourless oilwhich slowly crystallised to give a white solid. 1H NMR (400 MHz, CDCl3) 8.70 (s, 1H),8.40 (s, 1H), 7.20 (brs, 1H), 1.55 (s, 9H).

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; SYNGENTA PARTICIPATIONS AG; WAILES, Jeffrey, Steven; CARTER, Neil, Brian; CLOUGH, John, Martin; WILLIAMS, John; (48 pag.)WO2019/57724; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 59303-10-5, name is 2-Chloro-5-methylpyrazine, 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 59303-10-5, Product Details of 59303-10-5

To a solution of rac- I -((2S,3R,4R)-4-amino-2-ethyl-3-methyl-6-morpholino-3,4-dihydroqu inolin1(2H)-yl)ethanone (for a preparation see Intermediate 73, 50 mg, 0.158 mmol) in 1,4-dioxane (1.5 ml) was added tris(dibenzylideneacetone)dipalladium(0) (28.8 mg, 0.032 mmol), Davephos (12.40mg, 0.032 mmol), sodium tert-butoxide (30.3 mg, 0.315 mmol) and 2-chloro-5-methylpyrazine (40.5 mg, 0.315 mmol). The reaction mixture was heated under microwave conditions, using initial normal absorption setting, to 120 C for 30 mm. The sample was diluted with ethyl acetate (5 mL) and loaded onto a celite cartridge (2.5 g). The cartridge was washed with further ethyl acetate (2×10 mL), and the combined fractions dried under a stream of nitrogen. The sample was dissolved in DMSO(2×1 mL) and purified by MDAP (HpH). The solvent was blown down under a stream of nitrogen to give the required product (14 mg) as a yellow gum. LCMS (2 mm HpH): Rt = 0.87 mi [MH] = 410.

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-5-methylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO.2) LIMITED; AMANS, Dominique; ATKINSON, Stephen John; HARRISON, Lee Andrew; HIRST, David Jonathan; LAW, Robert Peter; LINDON, Matthew; PRESTON, Alexander; SEAL, Jonathan Thomas; WELLAWAY, Christopher Roland; WO2014/140076; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, 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 109838-85-9, name: (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine

Step B – Preparation of Compound Int-15b Int-15bTo a solution of (2R)-(-)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine (0.61 g, 4.36 mmol) in THF (8 mL) was added n-BuLi (2.5 M in hexane, 1.8 mL, 4.58 mmol) at -78 °C. After allowed to stir for 0.3 hours, Compound Int-15a (2.75 g, 6.98 mmol) in 2 mL of THF was added and the mixture was allowed to stir at the temperature for 4 hours. The reaction was quenched by saturated aqueous H4C1 solution and the organic layers were extracted with EtOAc. The combined organic solution was washed with brine solution, dried (Na2S04), and concentrated in vacuo. The residue obtained was purified using ISCO 40 g column (gradient from 0percent to 2.5percent ether in hexane) to provide Compound Int-15b, 783 mg (44percent). 1H MR (CDC13) delta 4.05 (m, 1H), 3.96 (t, J= 3.4 Hz, 1H), 3.72 (s, 3H), 3.71 (s, 3H), 3.49 (dd, 7= 2,8, 0.4 Hz, 1H), 3.26 (dd, 7= 6, 9.4 Hz, 1H), 2.30 (m, 1H), 1.96 (m, 1H), 1.60 (m, 2H), 1.37-1.17 (m, 3H), 1.08 (d, 7= 6.9 Hz, 3H), 0.99-0.86 (m, 2H), 0.72 (d, 7= 6.6 Hz, 3H), 0.49 (dd, 7= 11.0, 14.4 Hz, 1H), 0.35 (dd, 7= 11.0, 14.2 Hz, 1H), 0.16 (s, 6H).

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; MERCK SHARP & DOHME CORP.; DWYER, Michael P; KEERTIKAR, Kartik M; COBURN, Craig A; WU, Hao; HU, Bin; ZHONG, Bin; ZHANG, Chengren; DAN, Zhigang; TONG, Ling; YU, Wensheng; WO2012/41227; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 59303-10-5, 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 59303-10-5 as follows.

A mixture of 2-chloro-5-methylpyrazine (300 mg, 1.6 mmol), (R)-tert-butyl 3-aminopyrrolidine-l- carboxylate (206 mg, 1.6 mmol), BINAP (199 mg, 0.3 mmol), Pd2(dba)3 (73 mg, 0.08 mmol) and t- BuONa (307 mg, 3.2 mmol) in toluene (10 mL) was stirred at 80C under N2 for 3 hours. The mixture was cooled to RT and concentrated. The residue was purified by reverse phase chromatography to afford (R)-tert-butyl 3-((5-methylpyrazin-2-yl)amino)pyrrolidine-l-carboxylate (240 mg, 54%) as yellow oil. [M+H] Calc?d for Ci4H22N402, 279.1; Found, 279.1.

According to the analysis of related databases, 59303-10-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; KINNATE BIOPHARMA INC.; KANOUNI, Toufike; ARNOLD, Lee D.; KALDOR, Stephen W.; MURPHY, Eric A.; TYHONAS, John; (0 pag.)WO2020/6497; (2020); 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. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, A new synthetic method of this compound is introduced below., Application In Synthesis of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine

To a solution of (R)-2-isopropyl-3, 6-dimethoxy-2, 5-dihydropyrazine (500 mg, 2.72 mmol) and bis(chloromethyl) dimethylsilane (636 mg, 4.08 mmol) in THF (10 mL) under N2atmosphere in a dry ice/acetone bath was slowly n-BuLi (1.6 M in hexane, 2 mL, 3.2 mmol) via an injection syringe. After addition, the reaction was stirred at room temperature overnight. The reaction mixture was cooled to 0° C. and quenched by dropwise addition of water. The resulting mixture was extracted with EtOAc. The organic layer was washed by brine, dried over anhydrous Na2SO4and concentrated. The obtained crude product was purified by column chromatography on silica gel eluted with PE/EtOAc (100:1 to 30:1) to give the title compound (640 mg, 77.5percent yield); LC/MS (ESI) m/z: 305 [M+H]

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; ACHILLION PHARMACEUTICALS, INC.; WILES, Jason, Allan; PHADKE, Avinash, S.; DESHPANDE, Milind; AGARWAK, Atul; CHEN, Dawei; GADHACHANDA, Venkat, Rao; HASHIMOTO, Akihiro; PAIS, Godwin; WANG, Qiuping; WANG, Xiangzhu; (905 pag.)WO2017/35353; (2017); 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. 173253-42-4, name is 2-Amino-5-bromo-6-chloropyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C4H3BrClN3

To a solution of 1-69 (100 mg, 0.2 mmol) in DMF are added 2-amino-5-bromo-6- chloropyrazine (51 mg, 0.24 mmol), Tetrakis (triphenylphosphine)palladium (0) (24 mg, 0.02 mmol) and 2M Na2C03 solution (2M aqueous)(0.5 mL, 1 mmol). The mixture is heated to 100 C for 1 hour in a microwave reactor. The mixture is cooled down and is extracted with H20 and EtOAc. The combined organic layer is dried with MgS04 and is filtered. The filtrate is concentrated and the residue is purified by silica gel flash column chromatography with 10% MeOH in CH2C12 as the eluent to afford 1- 155 (86 mg) (m/z: 493.2 [M++H]).

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; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; BARTOLOZZI, Alessandra; BOSANAC, Todd; CHEN, Zhidong; DE LOMBAERT, Stephane; HUBER, John; LO, Ho Yin; LOKE, Pui Leng; LIU, Weimin; MORWICK, Tina Marie; OLAGUE, Alan; RIETHER, Doris; TYE, Heather; WU, Lifen; ZINDELL, Renee; WO2012/24150; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem