Month: July 2021

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., Recommanded Product: 2-Amino-5-bromo-6-chloropyrazine

In a pressure tube were mixed 2-amino-5-bromo-6-chloropyrazine (2.00 g, 9.60 mmol), 3-fluor-ophenylboronic acid (1.48 g, 10.55 mmol), sodium carbonate (2.03 g, 19.19 mmol) in a 4:1 mixture of 1 ,4-dioxane : water (25 mL). The reaction mixture was sparged with argon and Pd(PPh3)4 (0.22 g, 0.20 mmol) was then added. The mixture was sparged with argon shortly and the vessel was sealed and the reaction mixture was heated at 10000 for 20h. After that time the reaction mixture was cooled down to r.t. filtered through Celite pad diluted with AcOEt, or-ganic layer was washed with NaHCO3, brine and dried over Na2SO4. Then the mixture was concentrated under reduced pressure. The obtained residue was purified by flash chromatography on silica eluting with hexane : EtOAc (1:0 – 1:1) to lead to the title product as a light yellow solid(1 .82 g, 85%). ESI-MS: 224.00 [M+H].

The synthetic route of 173253-42-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SELVITA S.A.; BOBOWSKA (NEE WITKOWSKA), Aneta; GALEZOWSKI, Michal; NOWAK, Mateusz; COMMANDEUR, Claude; SZEREMETA-SPISAK, Joanna; NOWOGRODZKI, Marcin; OBARA, Alicja; DZIELAK, Anna; LOZINSKA, Iwona; DUDEK (NEE SEDLAK), Marcelina; JANIGA, Anita; REUS, Jacek; WRONOWSKI, Marek; ZASTAWNA, Magdalena; RADZIMIERSKI, Adam; SWIRSKI, Mateusz; ZACHMANN, Julian; FABRITIUS, Charles-Henry; PORTER, Rod; FOGT, Joanna; (276 pag.)WO2019/2606; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 59489-71-3, These common heterocyclic compound, 59489-71-3, name is 2-Amino-5-bromopyrazine, 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 c-120 5-Bromo-pyrazin-2-ol Sodium nitrite (1,35 g, 19.53 mmol) was added portionwise to concentrated sulfuric acid (9.8 mL) at 0 C. The mixture was heated at 50 C. until all of the sodium nitrite had dissolved and the mixture was again cooled to 0 C. A solution of 5-bromo-pyrazin-2-ylamine (2.57 g, 14.68 mmol) in concentrated sulfuric acid (14.7 mL) was added dropwise to the nitronium solution at 0 C. The ice bath was removed, the mixture warmed to ambient temperature and stirred for 15 minutes before heating to 45 C. for seven minutes. After cooling to ambient temperature, the mixture was poured slowly with precaution into crushed ice water (100 mL). The aqueous phase was neutralized to pH 4 with 20% aqueous sodium hydroxide then extracted with ethyl acetate (3*100 mL). The combined organic extracts were washed with water (50 mL), dried (anhydrous magnesium sulfate), filtered, and evaporated to afford the title compound (1.88 g, 73%) as a yellow solid. 1H NMR (CDCl3, 300 MHz): delta 8.07 (1H, s), 7.62 (1H, d, J=3.0 Hz).

Statistics shows that 2-Amino-5-bromopyrazine is playing an increasingly important role. we look forward to future research findings about 59489-71-3.

Reference:
Patent; Pfizer Inc; US2005/187266; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products 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.

A solution of 2-aminopyrazine 1 (4.5 g, 47.4 mmol) in 50 mL DMF/MeCN solvent mixture (1:3) and a solution of l,3-dibromo-5,5-dimethylhydantoin 2 (13.6 g, 47.6 mmol, 2 eq. of “Br”) in 40 mL DMF/MeCN solvent mixture (1:3) were simultaneously added (using two syringe needles) to a solution of MeCN (100 mL) at 0C. The reaction mixture was stirred for one hour, quenched with aqueous sodium thiosulfate (I N, 200 mL) and concentrated under vacuum. The crude product (>99% conversion, 8 g) was dissolved in EtOAc and filtered through celite/charcoal and recrystallized from acetonitrile (4.0 g, 50% recovery). The reaction was scaled up to 12.0 g in two batches and the desired product 3 was analyzed by NMR and LC-MS. IH NMR (500 MHz, CDC13) delta 7.99 (s, IH); 13C NMR (126 MHz, CDC13) delta 151.92, 143.16, 142.99, 123.95, 123.56.

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

Reference:
Patent; DOW GLOBAL TECHNOLOGIES LLC; ROHM AND HAAS ELECTRONIC MATERIALS KOREA LTD.; ONDARI, Mark E.; WELSH, Dean M.; FROESE, Robert DJ; NA, Hong-Yeop; (38 pag.)WO2016/209895; (2016); 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. 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, This compound has unique chemical properties. The synthetic route is as follows., Formula: C6H8ClF3N4

General procedure: To the stirred reaction mixture of 3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,2,4-triazolo-[4,3-a]pyrazine hydrochloride(11) (300 mg, 1.32 mmol), TEA (0.55 mL, 3.95 mmol)and toluene (10 mL), substituted cyanates 12(a-e)/isocyanates12(f-j) (1.32 mmol) were added at ambient temperature.The reaction mass was agitated at 75-80 C until thecompletion of the reaction that was monitored by TLC. Thereaction mass was allowed to cool at ambient temperatureand it was washed sequentially with 3% aqueous HCl(5.0 mL) and then water (5.0 mL). The organic fraction wasconcentrated under vacuum at 50-55 C to obtain crudeproduct. It was purified by column chromatography using10-50% of EtOAc:hexane mixture as a mobile phase.

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 762240-92-6.

Reference:
Article; Mannam, Madhava Rao; Devineni, Subba Rao; Pavuluri, Chandra Mouli; Chamarthi, Naga Raju; Kottapalli, Raja Sekhara P.; Phosphorus, Sulfur and Silicon and the Related Elements; vol. 194; 9; (2019); p. 922 – 932;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 93049-39-9,Some common heterocyclic compound, 93049-39-9, name is 7-Chloropyrido[3,4-b]pyrazine, molecular formula is C7H4ClN3, 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 417- [3 -(Piperidin- 1 -ylmethv0phenyl1pyrido[3 ,4-61pyrazine4,5-Diamino-2-chloropyridine (35 mg, 0.24 mmol) was dissolved in ethanol (1 mL) and glyoxal (0.5 niL, 40% in water) was added. After standing for 18 h the mixture was partitioned between water and EtOAc (20 mL each). The organic phase was washed with water, dried (MgSO4) and concentrated in vacuo. The residue was dissolved in DME (0.7 mL), and 3-(piperidin-l-ylmethyl)phenylboronic acid pinacol ester hydrochloride (81 mg, 0.24 mmol), 2M aqueous sodium carbonate solution (0.35 mL, 0.7 mmol) and Pd(PPh3)4 (8 mg, 0.007 mmol) were added. The mixture was heated to 12O0C in a sealed tube, under microwave irradiation, for 20 minutes. After cooling, the mixture was partitioned between water and EtOAc (2 mL each). The organic phase was concentrated in vacuo and the residue was purified by preparative HPLC to give the title compound (53 mg, 64%) as a pale yellow gum. deltaH (CDCl3) 9.63 (d, IH), 9.03 (d, IH), 8.92 (d, IH), 8.37 (d, IH), 8.17 (s, IH), 8.08-8.14 (m, IH), 7.44-7.57 (m, 2H), 3.74 (s, 2H), 2.50-2.65 (m, 4H), 1.59-1.73 (m, 4H), 1.40-1.54 (m, 2H). LCMS (ES+) 305 (M+H)+, RT 1.89 minutes.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 7-Chloropyrido[3,4-b]pyrazine, its application will become more common.

Reference:
Patent; UCB PHARMA S.A.; BUeRLI, Roland; HAUGHAN, Alan, Findlay; MACK, Stephen, Robert; PERRY, Benjamin, Garfield; RAPHY, Gilles; SAVILLE-STONES, Elizabeth, Anne; WO2010/52448; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 14508-49-7, 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. 14508-49-7, name is 2-Chloropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

20.0 g (174.6 mmol) 2-chloropyrazine are added dropwise to 60.0 ml (61.7 g, 1.2 mol) hydrazine hydrate. The mixture is stirred at a bath temperature of 120 C. for 45 min. For working up, the cooled reaction mixture is left to stand at 2 C. for 12 h, the crystals which have precipitated out are filtered off and the residue on the filter is washed twice with petroleum ether. The residue is then recrystallized from toluene.Yield: 6.5 g (34% of th.)LC-MS (Method 1): Rt=0.49 min; MS (ESIpos): m/z=111 [M+H]+;1H-NMR (400 MHz, DMSO-d6): delta=8.11 (s, 1H), 7.94 (s, 1H), 7.90 (s, 1H), 7.70 (d, 1H), 4.29 (br. s, 2H).

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

Reference:
Patent; BAYER SCHERING PHARMA AKTIENGESELLSCHAFT; US2010/305085; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature 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.

Methyl 3-aminopyrazine-2-carboxylate (100 g, 653.0 mmol) and N- bromosuccinimide (1 16.2 g, 653.0 mmol) were stirred in MeCN (1.198 L) at ambient temperature for 15 hours. The resultant precipitate was isolated by filtration and washed with MeCN (10 mL) and diethyl ether (100 mL) to give the sub-title product as pale yellow flakes (123.73g, 82% Yield). 1H NMR (400.0 MHz, CDCl3) delta 4.00 (s, 3H), 6.47 (br s, 2H), 7.28 (s, 1H) and 8.31 (s, 1H) ppm; (ES+) 232.0.

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

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-Damien; DURRANT, Steven, John; YOUNG, Stephen, Clinton; STORCK, Pierre-Henri; VIRANI, Aniza, Nizarali; REAPER, Philip, Michael; PINDER, Joanne; WO2011/143423; (2011); 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 58139-04-1 as follows. Recommanded Product: 2-Iodo-3-methoxypyrazine

Intermediate 25 (0.15 g, 0.622 mmol) was dissolved in 1,4-dioxane (6 mL). 2-Iodo-3- methoxypyrazine (0.12 g, 0.508 mmol), cesium carbonate (0.405 g, 1.244 mmol, Iota, – bis(diphenylphosphino)ferrocene (0.052 g, 0.093 mmol) and tris(dibenzylideneacetone) dipalladium(0) (0.028 g, 0.031 mmol) were added. The reaction tube was sealed and the mixture was stirred at 160 C for 1 hour under microwave irradiation. After cooling, the reaction mixture was diluted with DCM and filtered over dicalite. The filtrate was concentrated in vacuo. The crude product was purified by flash column chromatography (silica gel; eluent: 7 M solution of ammonia in methanol/DCM 0/100 to 5/95). The desired fractions were collected and concentrated. This crude was further purified by preparative HPLC on (Chiralpal Diacel AS 20x250mm). Mobile phase (C02, MeOH with 0.2% iPrNH2) to yield compound 8 (0.010 g, 5% yield).

According to the analysis of related databases, 58139-04-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; JANSSEN PHARMACEUTICA NV; GIJSEN, Henricus, Jacobus, Maria; VAN BRANDT, Sven, Franciscus, Anna; WO2013/83556; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 41270-62-6, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 41270-62-6 name is 2-Chloro-6-phenylpyrazine, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

General procedure: The Miyaura borylation reactions were carried out as follows: Chloropyrazines (3.0 mmol), B2pin2 (838 mg, 3.3 mmol), Pd(OAc)2 (14 mg, 2 mol %), PCy3 (34 mg, 4 mol %) and AcOK (750 mg, 7.5 mmol) was added in a 50 ml three necked flask fitted with a condenser, and dioxane (15 ml) was added at last. Then the reaction mixture was stirred at a preheated oil bath 110 oC under nitrogen atmosphere for 10 min. After complete completion of starting material checked by TLC, the reaction was cooled to room temperature, EtOAc (20 ml) was added. After filtration through Celite and concentration under vacuo, the resulting residue was precipitated from n-hexane:Et2O to afford corresponding boronic esters.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Chloro-6-phenylpyrazine, and friends who are interested can also refer to it.

Reference:
Article; Lu, Hongtao; Wang, Shengqiang; Li, Jingya; Zou, Dapeng; Wu, Yusheng; Wu, Yangjie; Tetrahedron Letters; vol. 58; 9; (2017); p. 839 – 842;,
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. 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, A new synthetic method of this compound is introduced below., category: Pyrazines

Example 1: 3-nitro-1-(3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)propan-1-one (NPTP) [Show Image] The title compound was prepared using the method described in WO 2008/040974. A mixture of 3-nitropropionic acid (20.0 g, 0.168 mol), 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride (48.0 g, 0.21 mol) in acetonitrile (400 mL) is cooled to 0 C and 4-methylmorpholine (16.9 g, 0.168 mmol) is added, followed by N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride (48.4 g, 0.25 mol) after 5 min. The resulting mixture is stirred at room temperature for 20 hours. The resulting mixture is concentrated to about 2/3 of it volume and ethyl acetate is added (750 mL). The resulting mixture is washed twice with water (200 + 100 mL), sat. aq. sodium hydrogencarbonate (200 mL), brine (200 mL) and dried with sodium sulfate. The resulting clear solution is concentrated under reduced volume and MTBE is added (100 mL). The precipitated white solid is filtered off, washed with MTBE (200 mL) and dried under reduced pressure to yield 38.8 g (79 % yield) of NTPT as white powder.

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; LEK Pharmaceuticals d.d.; EP2392575; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem