Month: February 2021

Synthetic Route of 173253-42-4, These common heterocyclic compound, 173253-42-4, name is 2-Amino-5-bromo-6-chloropyrazine, 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 5-bromo-6-chloropyrazin-2-amine (200 mg, 0.98 mmol, 1 eq.) in DMF (3 mL) was added 3-methyl pyrazole (312 mg, 3.8 mmol, 5.0 eq.) and Cs2CO3 (1.24 g, 3.8 mmol, 5.0 eq.). The reaction mixture was allowed to heat at 100 C. for 16 h. The progress of the reaction was monitored by TLC and LCMS The reaction mixture was diluted with water (30 mL) and extracted using ethyl acetate (2*50 mL). The separated organic layer was dried over sodium sulfate and concentrated under reduced pressure. The crude product was purified by normal phase column chromatography to afford the desired product (16 mg, 54%). LCMS: 309 [M+1]+. 1H NMR: (400 MHz, DMSO-d6) delta 9.35 (s, 1H), 8.06 (s, 1H), 7.96 (d, J=1.32 Hz, 1H), 7.90 (d, J=8.77 Hz, 1H), 7.81 (d, J=2.19 Hz, 1H), 7.13 (dd, J=1.75, 8.77 Hz, 1H), 6.98 (s, 2H), 6.23 (d, J=2.19 Hz, 1H), 2.08 (s, 3H).

Statistics shows that 2-Amino-5-bromo-6-chloropyrazine is playing an increasingly important role. we look forward to future research findings about 173253-42-4.

Reference:
Patent; GiraFpharma LLC; PHAM, Son Minh; CHEN, Jiyun; ANSARI, Amantullah; JADHAVAR, Pradeep S.; PATIL, Varshavekumar S.; KHAN, Farha; RAMACHANDRAN, Sreekanth A.; AGARWAL, Anil Kumar; CHAKRAVARTY, Sarvajit; (120 pag.)US2019/23666; (2019); 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. 4858-85-9, name is 2,3-Dichloropyrazine, A new synthetic method of this compound is introduced below., Formula: C4H2Cl2N2

Under a nitrogen atmosphere,To a 25 mL test tube reactor was added substrate 2,3-dichloropyrazine 1 w (0.2 mmol,29.6 mg), KSAc(0.6mmol,68.4mg),DMC(1.0mmol,90mg),Pd(OAc)2(0.01mmol,2.3mg),PPh3 (0.02mmol,5.9mg),tBuOK(0.6mmol,69.2mg),and DMSO(2.0mL)..The reaction was heated to 120 C to carry out the reaction.After the TLC detection reaction was completed,The system was cooled to room temperature.The reaction was quenched with saturated aqueous ammonium chloride,And extracted with ethyl acetate (3 * 10 mL)The product was purified by column chromatography to give 28.2mg(82).of product 2w.

The synthetic route of 4858-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; East China Normal University; Jiang Xuefeng; Qiao Zongjun; (32 pag.)CN106866327; (2017); A;,
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. 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below. Product Details of 63286-28-2

(2) To a 100 mL eggplant flask were added 2-chloro-3-hydrazinylpyrazine (370 mg), diisopropylethylamine (1.3 mL), acetonitrile (15 mL), and the above 5-azaspiro[2.5]octane-5-carbonyl chloride (435 mg) under argon gas flow, and the resulting mixture was stirred at 80 C. for 100 minutes. After the reaction was completed, the mixture was concentrated under reduced pressure, the resulting residues were subjected to silica gel chromatography using YAMAZEN medium pressure preparative (Silica L (40 g)), the fractions comprising the target compound (Rf value=0.4 (hexane:ethyl acetate=1:1)) were collected, and concentrated under reduced pressure to give the title compound (330 mg) (yield 47%) as a slightly yellow foam. MS(CI) m/z: 282/284 [M+H]+

The synthetic route of 63286-28-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MITSUBISHI TANABE PHARMA CORPORATION; UBE INDUSTRIES, LTD.; NAKAJIMA, Tatsuo; HAYASHI, Norimitsu; ISHIZAWA, Kouhei; TSUZAKI, Yasunori; IWAMURA, Ryo; TSUBOIKE, Kazunari; US2019/185479; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

14508-49-7, name is 2-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. Product Details of 14508-49-7

[Referential Example 2] 2-Hydrazinopyrazine [Show Image] Hydrazine monohydrate (21.80 g) was added to 2-chloropyrazine (10.44 g) in ethanol (65 mL) at room temperature, and the resultant mixture was refluxed for 17 hours, followed by cooling in air. The reaction solvent was evaporated under reduced pressure, and then benzene was added to the residue. The resultant mixture was subjected to decantation, to thereby remove an insoluble matter. The benzene was evaporated under reduced pressure. Hexane was added to the resultant solid, and the mixture was subjected to filtration, to thereby give the title compound (4.67 g, 47%). 1H-NMR(400MHz,CDCl3)delta:7.89(1H,d,J=2.7Hz), 7.99-8.05(1H,m), 8.20(1H,d,J=1.5Hz). ESI-MS m/z:111(M+H)+.

The synthetic route of 14508-49-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; DAIICHI PHARMACEUTICAL CO., LTD.; EP1762568; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 6966-01-4, These common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-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.

4- (PYRROLIDIN-1-YLSULFONYL) PHENYLBORONIC acid (0.33 g, 1.29 mmol), methyl 3-amino-6- BROMOPYRAZINE-2-CARBOXYLATE (0.25 g, 1.08 mmol; described in: H. Ellingson, J. Amer. Chem. Soc. 1949, 2798), K3PO3 (3 M, 1.1 mL, 3.2 mmol), and Pd (dppf) Cl2 (0.044 g, 54 JUMOL) were suspended in ethylene glycol dimethyl ether/water (1.5 : 0.5 mL) and heated in a microwave oven at 160 C for 10 min. The reaction was repeated 3 times. The combined product mixtures were evaporated with silica gel and the crude product was purified by chromatography on silica gel using a HEPTAN/ETHYLACETATE gradient as the eluent to give 0.96 g (82% yield) of the title compound: MS (ES) m/z 363 (M+1).

The synthetic route of 6966-01-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ASTRAZENECA AB; WO2004/55009; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 41110-34-3, These common heterocyclic compound, 41110-34-3, name is Ethyl 5-methylpyrazine-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.

The reaction was carried out, under nitrogen, in a 500 mL¡Á4 neck flask equipped with a mechanical stirrer, water condenser (with gas inlet), and a thermocouple. The reactor was charged with sodium tungstate dihydrate (1.35 g) and water (30 g). The mixture was stirred to dissolve the solid (10 minutes). Aqueous sulfuric acid (50%) was added bringing the pH down to about 3.5. Aqueous 35% hydrogen peroxide (22.36 g) was added and the solution was stirred for 15 minutes. 5-Methylpyrazinecarboxylic acid ethyl ester (27.27 g) was then added. The reaction mixture was warmed to 70 C. and then stirred for a total of 12 hours after which the reaction was checked by GC or GC/MS and was found to be complete. The resulting solution was concentrated under reduced pressure to yield a light yellow solid. The reaction mixture was cooled in an ice-bath for 3 hours. The product was collected by filtration and washed with ice water (25 g). Drying the solid at 60 C. under house vacuum yielded 20.57 g (69%) of the ester N-oxide.

The synthetic route of 41110-34-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ISP INVESTMENTS INC.; US2005/261312; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4774-14-5, The chemical industry reduces the impact on the environment during synthesis 4774-14-5, name is 2,6-Dichloropyrazine, I believe this compound will play a more active role in future production and life.

Synthesized according to the general procedure given in Walker II, J. A.; Liu, W.; Wise, D. S. Drach, J. C.; Townsend, L. B. et. al. J. Med. Chem. 1998, 41, 1236-1241. The mono anion of 2,6-dichloro-pyrazine was generated as described and quenched with 500 mol % MeI to provide a 65% isolated yield of the title compound.

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, 2,6-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Termin, Andreas; Grootenhuis, Peter D.J.; Wilson, Dean M.; Molteni, Valentina; Mao, Long; Castellino, Angelo; Yang, Zhicai; Pechulis, Anthony; Suto, Mark; US2003/229091; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 52333-42-3,Some common heterocyclic compound, 52333-42-3, name is 7-Bromopyrido[2,3-b]pyrazine, molecular formula is C7H4BrN3, 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 105 Under nitrogen atmosphere, to a mixture of 7-bromopyrido[2,3-b]pyrazine (300 mg), methyl boronate (100 mg) and cesium carbonate (930 mg) were added dioxane (7.0 ml), bis(dibenzilidenacetone)-palladium (80.0 mg) and triphenylphosphine (87.0 mg), and the mixture was stirred at 100 C. for 2.5 hours. To the reaction solution was added a saturated aqueous sodium hydrogen carbonate solution, and the mixture was extracted three times with ethyl acetate. The extracts were combined, washed with a saturated brine, dried over magnesium sulfate, and filtered. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column (hexane/ethyl acetate=3/1?1/1?0/1?ethyl acetate/ethanol=10/1) to give 7-methyl-pyrido[2,3-b]pyrazine (125 mg, 60%). 1H NMR (CDCl3, 400 MHz) delta 9.06 (d, 1H, J=2.3 Hz), 9.02 (d, 1H, J=1.7 Hz), 8.91 (d, 1H, J=1.7 Hz), 8.24 (d, 1H, J=2.3 Hz), 2.65 (s, 3H).

The synthetic route of 52333-42-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Tokunaga, Teruhisa; Hume, William Ewan; Kitoh, Makoto; Nagata, Ryu; US2003/181496; (2003); 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. 56423-63-3, name is 2-Bromopyrazine, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 2-Bromopyrazine

Example 269(S)-3-(4-chlorophenyl)-4-(3-(pyrazin-2-yloxy)phenyl)oxazolidin-2-one [00252] Reference: Org Lett 2003, 5(21), 3799. A small reaction tube fitted with a screw cap containing a septum is charged with (S)-3-(4-chlorophenyl)-4-(3-hydroxyphenyl)- oxazolidin-2-one (0.06 mmol), 2-bromopyrazine (0.076 mmol), CuI (0.04 mmol), NN- dimethylglycine (0.04 mmol), Cs2CO3 (0.13 mmol) and 1,4-dioxane (1 mL) is stirred at 1200C for 18h. The reaction mixture is then cooled to room temperature and filtered through a Whatman 0.42 muM filter and purified by preparative HPLC (C-18, 10-90 % ACnu/water (0.05 % TFA)). 1H nuMR (CDCl3, 400 MHz) delta 8.41 (d, J = 1.2 Hz, IH), 8.29 (d, J = 2.8 Hz, IH), 8.04 (dd, J = 2.8, 1.2 Hz, IH), 7.43 (t, J = 8.0 Hz, IH), 7.34 (d, J = 8.8 Hz, 2H), 7.24 (d, J = 8.2 Hz, 2H), 7.12-7.19 (m, 2H), 7.10 (s, IH), 5.37 (dd, 7 = 8.8, 6.0 Hz, IH), 4.80 (t, J = 8.8 Hz, IH), 4.26 (dd, 7 = 8.8, 6.0 Hz, IH); HPLC-MS calculated for Ci9Hi4ClN3O3 (M+H+) 368.1, found 368.1.

According to the analysis of related databases, 56423-63-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; IRM LLC; WO2008/76754; (2008); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 123-32-0, These common heterocyclic compound, 123-32-0, name is 2,5-Dimethylpyrazine, 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.

Preparation of 3,6-dimethyl-2- (4-trifluoromethyl) benzoyl pyrazine, comprising the steps of:(1) 2,5-dimethyl pyrazine take 0.2mmol, 3- trifluoromethylbenzoyl acid 0.4mmol, silver phosphate 0.02mmol, potassium persulfate 0.4mmol, 1.4mL was added dichloromethane, 0.6mL after the mixture was prepared with distilled water, and the mixture was placed in a reaction tube of 5mL was heated in an oil bath at 40 , the reaction 24h, cooled to room temperature to obtain a reaction solution;(2) The step (1) the resulting reaction mixture was directly concentrated to give a concentrate, the concentrate with ethyl acetate / petroleum ether = 1/2 (v / v) as the developing solvent, separation by thin layer chromatography to give 45mg target The product, in 43% yield.

The synthetic route of 123-32-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Henan Agricultural University; Wu Zhiyong; Zhao Mingqin; Li Yuan; (10 pag.)CN108101856; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem