Tag: M.W=100-200

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, Formula: C9H16N2O2

At -78° C. 7.80 ml (19.5 mmol) n-butyllithium (2.5 M in hexane) were added dropwise to 2.90 ml (16.2 mmol) (R)-2-isopropyl-3.6-dimethoxy-2,5-dihydropyrazine in 55 ml THF and the mixture was stirred for 2 h at -50° C. Then at -70° C. 4.25 g (17.8 mmol) (iodomethyl)cycloheptane in 15 ml THF were added dropwise, then the mixture was stirred for 30 min at -78° C., for 3 h at 0° C. and overnight at RT. After the addition of water and methanol it was stirred for 20 min at RT. Ethyl acetate was added and the mixture was extracted with saturated, aqueous saline solution. The organic phase was dried and evaporated to dryness by rotary evaporation. The residue was purified by flash chromatography. The fractions containing the product were combined and concentrated by rotary evaporation. The residue obtained was combined with acetonitrile, water and 1M hydrochloric acid and stirred overnight at RT. The acetonitrile was evaporated off and the aqueous phase was neutralised with potassium hydrogen carbonate. It was extracted with ethyl acetate. The combined organic phases were dried and evaporated to dryness by rotary evaporation.Yield: 1.04 g (32percent of theoretical)ESI-MS: m/z=200 (M+H)+ Rt (HPLC): 0.96 min (method A)The enantiomeric (R)-compound may be obtained analogously to the method of synthesis described above using the corresponding (R)-configured reaction component.

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; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; US2012/196872; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 914452-71-4, 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. 914452-71-4, name is 2-Bromo-6-methylpyrazine, This compound has unique chemical properties. The synthetic route is as follows.

To a solution of 2-bromo-6-methyl-pyrazine (3.0 g, 17.31 mmol) in CCl4 (25 mL) was added NBS (4.60 g, 26.01 mmol) and AIBN (0.248 g, 1.734 mmol) at RT. The mixture was stirred at 55 C. for 48 h. H2O was added followed by extraction with EtOAc (3*100 mL). The combined organics were washed with brine, dried (Na2SO4) and concentrated in vacuo. The residue was purified over silica eluting with 5% EtOAc:Hexane to obtain i (1.40 g, 32%). 1H NMR (CDCl3, 400 MHz): delta 8.64 (s, 1H), 8.62 (s, 1H) and 4.50 (s, 2H).

The chemical industry reduces the impact on the environment during synthesis 2-Bromo-6-methylpyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; Biota Europe Ltd.; Lunniss, Christopher James; Palmer, James T.; Pitt, Gary Robert William; Davies, David; Axford, Lorraine Claire; US2013/252938; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 98-97-5,Some common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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.

Pyrazine-2-carb aldehyde A round bottom flask was charged with pyrazine carboxylic acid (17.7 g, 140 mMol), methanol (200 mL) and conc. sulphuric acid (2 mL) and the mixture was stirred at reflux for 4 hrs then left to stand overnight. The next day the mixture was refluxed for 2 more hours. The solvent was then evaporated in vacuo, the residue was diluted with dichloromethane and neutralised with 20% sodium bicarbonate solution. The dichloromethane phase was dried over MgS04 and evaporated to give the crude product as an off-white solid. Purification by column chromatography (silica gel, dichloromethane) gave pyrazinecarboxylic acid methyl ester 13.5 g as a white solid.

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

Reference:
Patent; F2G LTD; WO2005/92304; (2005); A2;,
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. 75907-74-3, name is (3,5,6-Trimethylpyrazin-2-yl)methanol, A new synthetic method of this compound is introduced below., Recommanded Product: (3,5,6-Trimethylpyrazin-2-yl)methanol

In a 50 ml round-bottom flask the compound TMP-OH (1.52 g 10 mmol) was added and dissolved in 20 mL of anhydrous ethanol active manganese dioxide (2.61 g 30 mmol) was added heated to reflux for 3 hours and monitored by TLC until the starting material completely comsumed and the resulting material was filtered and concentrated and separated with column chromatography eluted with ethyl acetate /petroleum ether (11) to give the compound TMP-CHO as a white solid (0.99 g 66) .

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; GUANGZHOU MAGPIE PHARMACEUTICAL CO., LTD; WANG, Yuqiang; YOUDIM, Moussa B.H.; SUN, Yewei; ZHANG, Zaizun; ZHANG, Gaoxiao; YU, Pei; YI, Peng; LIANG, Ming; LIU, Wei; WO2015/109935; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 16298-03-6,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.

A mixture of methyl 3-aminopyrazine-2-carboxylate (6.30 g, 41.14 mmol, 1 eq.) andiV- o bromosuccinimide (7.322 g, 41.14 mmol, 1 eq.) in 100 mL acetonitrile was refiuxed for 2 h until there was no starting material left according to LC/MS. The solvent was removed in vacuo. To the residue was added isopropanol. After filtration, the crude product was collected as a solid. Additional product could be collected from the mother solution. Thus, 12.136 g of crude product was obtained (127 %). The crude product was used directly in 5 the next step without further purification.1H NMR (400 MHz, DMSO-cfc) delta (ppm) 3.85 (s, 3H)5 7.55 (br s, 2H), 8.42 (s, IH).

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

Reference:
Patent; ASTRAZENECA AB; WO2007/61360; (2007); A2;,
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 59489-71-3 as follows. Recommanded Product: 59489-71-3

In a sealed tube, sodium methoxide (25 wt. %, 10 mL) was added to a suspension of 5-bromopyrazin-2-amine (1.12 g, 6.44 mmol) in MeOH (10 mL). The reaction was stirred at 100C for 40 h. At 15 h reaction time, reaction is about 40 % complete by LCMS. At 40 h reaction time, reaction is about 90% complete. After concentration the residue was taken up in EtOAc and extracted with brine, dried over sodium sulfate, concentrated and purified by flash chromatography on a 120 g silica gel cartridge with 30 to 50% EtOAc in hexane, 45 min, at 35 mL/min. Pure fractions were pooled, concentrated and dried under high vac to give 5-methoxypyrazin-2-amine (455 mg, 57 %).1H NMR (400 MHz, CDCl3) d ppm 7.75 (1 H, d, J=1.26 Hz), 7.55 (1 H, d, J=1.51 Hz), 4.12 (2 H, br. s.), 3.87 (3 H, s). LCMS (method K) tR, 0.55min., MH+ = 126.1.

According to the analysis of related databases, 59489-71-3, the application of this compound in the production field has become more and more popular.

Reference:
Article; Iwuagwu, Christiana; King, Dalton; McDonald, Ivar M.; Cook, James; Zusi, F. Christopher; Hill, Matthew D.; Mate, Robert A.; Fang, Haiquan; Knox, Ronald; Gallagher, Lizbeth; Post-Munson Amy Easton, Debra; Miller, Regina; Benitex, Yulia; Siuciak, Judy; Lodge, Nicholas; Zaczek, Robert; Morgan, Daniel; Bristow, Linda; Macor, John E.; Olson, Richard E.; Bioorganic and Medicinal Chemistry Letters; vol. 27; 5; (2017); p. 1261 – 1266;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 32111-28-7, A common heterocyclic compound, 32111-28-7, name is N-Methylpyrazin-2-amine, molecular formula is C5H7N3, 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.

General procedure: A magnetically stirred solution of xanthate (2.0 equiv) and pyrazine (1.0 equiv) in 1, 2-dichloroethane (1.0mmol/mL according to the xanthate) was refluxed for 15min under a flow of nitrogen. Then dilauroyl peroxide (DLP) was added portionwise (20mol % according to the xanthate) every hour until total consumption of one substrate. The reaction mixture was then cooled to room temperature and the solvent was evaporated under reduced pressure. Unless otherwise specified, the crude product was purified by flash chromatography on silica gel.

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; Huang, Qi; Qin, Ling; Zard, Samir Z.; Tetrahedron; vol. 74; 40; (2018); p. 5804 – 5817;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 313339-92-3, name is 3,5-Dichloropyrazine-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 313339-92-3, Quality Control of 3,5-Dichloropyrazine-2-carbonitrile

107281 3,5-Dichloropyrazine-2-carbonitrile (Example 12, Step 2, 31.0 g, 178.18 mmol) was dissolved in anhydrous diethyl ether (890 mL, 0.2 M) and cooled to -78 C. Then MeMgBr indiethyl ether (3.0 M, 65.3 mL, 190 mmol) was added slowly to maintain low temperature. After the addition was complete, the mixture was slowly warmed room temperature and stirred at room temperature for 1 h. The mixture was poured into a beaker containing a mixture of HC1 in water (1.0 M, 1 L) and ice (1 kg). The mixture was stirred vigorously for 10 mm. The mixture was extracted with diethyl ether (3 X 1 L). The combined organic layers were dried over Na2504 andconcentrated under reduced pressure to afford the title compound as an orange oil (34 g, 99% yield). The mixture was used for the next reaction without further purification. ?H NMR (400 IVIHz, CDC13): ppm 8.56 (s, 1H), 2.71 (s, 3H).

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, 3,5-Dichloropyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; FLX BIO, INC.; BECK, Hilary, Plake; BIANNIC, Berenger; BUI, Minna Hue, Thanh; HU, Dennis, X.; KETCHAM, John, Michael; POWERS, Jay, Patrick; REILLY, Maureen, Kay; ROBLES-RESENDIZ, Omar; SHUNATONA, Hunter, Paul; WALKER, James, Ross; WUSTROW, David, Juergen; YOUNAI, Ashkaan; ZIBINSKY, Mikhail; (396 pag.)WO2018/22992; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, 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. Recommanded Product: 16298-03-6

(A) Methyl 2-bromo-3-pyrazine carboxylate To a stirred mixture of 12.7 g. of methyl 2-amino pyrazine carboxylate and 47 ml. of 48% hydrobromic acid there was added, dropwise, 12.6 ml. of bromine keeping the temperature at 0. A solution of 14.4 g. of sodium nitrite in 60 ml. of water was then added, dropwise, at 0 and the reaction mixture stirred for 15 minutes. The reaction mixture was basified to pH 8 with sodium bicarbonate and extracted with ethyl acetate and again with chloroform. The organic layers were dried over magnesium sulfate, filtered and concentrated to a yellow oil. Recrystallization from ether-hexane yielded the product, m.p. 43-45 C.

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

Reference:
Patent; Schering Corporation; US4632923; (1986); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 4774-14-5, 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 4774-14-5 as follows.

2,2,6,6-tetramethylpiperidine (2.84 g, 20.1 mmol) in THF (250 mL) at -100C was added n-butyllithium (13.8 mL, 22.1 mmol). The solution was stirred for 20 minutes and cooled to -90C. 2,6-Dichloropyrazine (3.0 g, 20.1 mmol) in THF (10 mL) was added to the solution followed by carbon dioxide (89 g, 2014 mmol) as dry ice powder. The mixture was then allowed to warm to room temperature while stirring. The reaction mixture was concentrated under reduced pressure, diluted with water (20OmL) and acidified with 10% aq. HCl solution to pH 2. Extraction with EtOAc (x3) was followed by extraction with saturated aq. NaHCO3 solution. The aquous solution was acidified carefully with 10% aq. HCl solution to pH 2. The solution was extracted with EtOAc(x3) and the resulting solution was washed with water and brine. The organics were dried over anhydrous MgSO4 and concentrated. The resulting solid was trituated with Hex/chloroform (1 :1) and the remaining solid was filtered and washed with hexane to provide the title compound as an off-white solid (1.78 g, 9.22 mmol, 45.8% yield); IH NMR (400 MHz, DMSO-J6) delta ppm 8.90 (s, 1 H).

According to the analysis of related databases, 4774-14-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SIGNAL PHARMACEUTICALS, LLC; WO2009/89042; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem