Month: March 2021

Reference of 2423-65-6, 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. 2423-65-6, name is Pyrazine 1-oxide, This compound has unique chemical properties. The synthetic route is as follows.

Preparation 28 2-Amino-6-cyanopyrazine This intermediate was prepared via a stepwise procedure. A mixture of 21 g. of pyrazine-2-carboxamide, 85 ml. of glacial acetic acid, and 75 ml. of 30 percent hydrogen peroxide was heated at about 55 C. for about 35 hours. The reaction product mixture was cooled and filtered. The solid which was collected was extracted with n-butanol and the extracts discarded. The solid which was insoluble in n-butanol was recrystallized from hot water to yield a white solid having a melting point of about 302-305 C. The solid was identified by elemental analyses as pyrazine-2-carboxamide 4-oxide. To a mixture of 4 g. of the pyrazine oxide (prepared above) in 40 ml. of dimethylformamide cooled in an ice bath, there was quickly added 12 ml. of phosphorus oxychloride. The reaction mixture was poured into water and the aqueous mixture extracted with ethyl acetate, and the extracts saved. Additional water was added to the aqueous layer and the aqueous mixture extracted with hexane-ether. The ethyl acetate and hexane-ether extracts were combined and concentrated in vacuo to leave a residue. The residue was identified by elemental analyses and IR spectrum as 2-chloro-6-cyanopyrazine, and was used without further purification in the next step. A mixture of 1 g. of the above chlorocyanopyrazine and 25 ml. of dimethyl sulfoxide was prepared and anhydrous ammonia was bubbled thereinto. The reaction mixture was stirred overnight and then poured into water. The aqueous mixture was extracted with ethyl acetate, and the extracts dried. The drying agent was filtered off and the solvent removed in vacuo to leave a solid which was identified by its IR spectrum as 2-amino-6-cyanopyrazine. It was used as is without further purification in the preparation of final products of the invention.

The chemical industry reduces the impact on the environment during synthesis Pyrazine 1-oxide. I believe this compound will play a more active role in future production and life.

Reference:
Patent; Eli Lilly and Company; US4293552; (1981); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 313339-92-3, name is 3,5-Dichloropyrazine-2-carbonitrile, molecular formula is C5HCl2N3, 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. Recommanded Product: 3,5-Dichloropyrazine-2-carbonitrile

j1416] Compound 356 from above was dissolved in 10 mE DMF. To it were added 3,5-dichloropyrazine-2-cabonitrile (250 mg, 1.42 mmol) and DIEA (500 IL, 2.84 mmol). The mixture was stirred at RT for 2 hours, diluted with 150 mE EtOAc, washed with water x3, dried, concentrated in vacuo, and subjected to silica flash column using 0 to 3% MeOR in DCM to isolate 3-chloro-54(2R,3R)-2-methyl-3-(3-methyl- 2-oxoimidazolidin-1 -yl)piperidin-1 -yl)pyrazine-2-carboni- trile (357, 200 mg, 42% yield).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 313339-92-3, its application will become more common.

Reference:
Patent; JIA, Zhaozhong J.; CHEN, Wei; THOMAS, William D.; US2015/158865; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1379338-74-5,Some common heterocyclic compound, 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine, molecular formula is C7H3Cl2N3, 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 (S)-tert-butyl 3-(aminomethyl)piperidine-1-carboxylate (100 mg, 0.5 mmol), 5,7-dichloropyrido[4,3-b]pyrazine (100 mg, 0.5 mmol) and DIPEA (77 mg, 0.6 mmol) in THF (5 mL) was stirred at room temperature for 4 hours. The volatiles were removed under reduced pressure, and the residue was treated with ethyl acetate, with brine, and concentrated to give the crude 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 5,7-Dichloropyrido[3,4-b]pyrazine, its application will become more common.

Reference:
Patent; HUTCHISON MEDIPHARMA LIMITED; Su, Wei-Guo; Deng, Wei; Ji, Jianguo; US2014/121200; (2014); 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. 109-08-0, name is 2-Methylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 109-08-0

A 2.5 M hexanes solution of n-BuLi (18.0 mL, 45 mmol) was added to a -78 0C THF solution (60 mL) of t-BuOK (5.1 g, 45 mmol) and diisopropylamine (6.3 mL, 45 mmol). After 5 min at -78 0C the yellow mixture was warmed to -40 0C. Neat methylpyrazine (2.7 mL, 30 mmol) was added and the mixture rapidly turned dark red. After 30 min at – 40 0C the mixture was cooled to -78 0C and neat allyl bromide (7.6 mL, 90 mmol) was added. After 30 min at -78 0C water was added and the mixture was partially concentrated to remove volatile organics. The resulting mixture was extracted with dichloromethane and the combined organics were dried (Na2SO4), concentrated, and purified via column chromatography to give 2.2 g of 2-but-3-enyl-pyrazine.

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 109-08-0.

Reference:
Patent; JANSSEN PHARMACEUTICA NV; BARBAY, J., Kent; LEONARD, Kristi; CHAKRAVARTY, Devraj; SHOOK, Brian, Christopher; WANG, Aihua; WO2010/45015; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference 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.

Diphenyl phosphorylazide (8.6 g) was added dropwise to a solution of pyrazine-2- carboxylic acid (3 g) in THF (30 ml) and TEA (9 ml) and the resulting reaction mixture was stirred at RT for 2 hours. On completion, THF was removed under reduced pressure to give a residue, which was further purified by column chromatography (SiO2, gradient 10-40 % EtOAc/n-hexane) yielding the desired product (2.5g, 70%).

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; SENTINEL ONCOLOGY LIMITED; WO2007/144579; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 274-79-3, These common heterocyclic compound, 274-79-3, name is Imidazo[1,2-a]pyrazine, 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.

Imidazo[1 ,2-a]pyrazine(l1 ) (4.38 g, 36.8 mmol) was dissolved in methanol (100 mL) and hydrogenated at 1 atm/25 0C hydrogen over platinum(IV) oxide (0.522 g, 1.838 mmol) for 24 h. The catalyst was filtered and the filtrate concentrated to afford afford product in 4.8 g that was used without further purification. LC/MS = 124 (M+H)+, retention time = 0.34 minutes (2 minute method (high pH)).

The synthetic route of 274-79-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GLAXO GROUP LIMITED; DEAN, David Kenneth; MUNOZ-MURIEDAS, Jorge; SIME, Mairi; STEADMAN, Jon Graham Anthony; THEWLIS, Rachel Elizabeth Anne; TRANI, Giancarlo; WALL, Ian David; WALTER, Daryl Simon; WO2010/125101; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 313339-92-3,Some common heterocyclic compound, 313339-92-3, name is 3,5-Dichloropyrazine-2-carbonitrile, molecular formula is C5HCl2N3, 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 3,5-dichloropyrazine-2-carbonitrile (100 mg, 0.578 mmol), phenylboronic acid (0.635 mmol, 77.5 mg, 1.1 equiv), [1,1?- bis(diphenylphosphino)ferrocene]dichloropalladium(II) (0.029 mmol, 5 mol%) in degassed dioxane/water 4:1 (6 mL) was sodium carbonate (0.635 mmol, 1.1 equiv) and the reaction mixture was stirred for 4h under nitrogen at 100oC. Once complete, the reaction was diluted with EtOAc and water. The organic phase was separated and aqueous layer was extracted twice with EtOAc, dried over magnesium sulfate, filtered and concentrated under reduced pressure to give product: ESI-MS (m/z): 215.1

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3,5-Dichloropyrazine-2-carbonitrile, its application will become more common.

Reference:
Patent; CASE WESTERN RESERVE UNIVERSITY; BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM; MARKOWITZ, Sanford; ANTCZAK, Monika; READY, Joseph; ZHANG, Youngyou; (332 pag.)WO2018/218251; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 109-08-0, name is 2-Methylpyrazine, 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. Product Details of 109-08-0

EXAMPLE 13 4-(2-Pyrazinyl)-1-butene (1300) To a mixture of 15.6 g of sodium amide in 400 ml of ammonia was added dropwise 37.6 g of 2-methylpyrazine. The mixture was stirred for 2 hours and then 24.2 g of allyl bromide in 50 ml of ether was slowly added. This was stirred for 2 hours, 25 g of ammonium chloride added and the ammonia replaced by 500 ml of ether. 250 ml of water was added, the organic layer separated and the aqueous layer extracted twice with ether. The combined organic layers were then concentrated at reduced pressure. The residue was fractionated by distillation to give 20.5 g of product (1300), b.p. 96¡ã-7¡ã (25 mm). UV 2percent EtOH max: 268 (3.82), 273 (3.82). From the above distillation was also obtained 5.4 g of a second product, characterized as the bisalkylated compound, 4-(2-pyrazinyl)-1,6-beptadiene (1301), b.p. 122¡ã-3¡ã (24 mm). UV 10percent EtOH max: 269 (3.83), 273 (3.83).

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

Reference:
Patent; The Coca-Cola Company; US4638005; (1987); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 109-08-0, 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. 109-08-0, name is 2-Methylpyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Under an argon gas flow, diisopropylamine (7.70 g) was dissolved in tetrahydrofuran (50 ml), followed by stirring at -78C. A solution of 1.52 M n-butyl lithium in hexane (50 ml) was slowly added dropwise. After the dropwise addition, the mixture was slowly returned to room temperature over 30 minutes and cooled to -78C again to prepare lithium diisopropylamide. To this was added 2-methylpyrazine (4.29 g), the solution was stirred at 0C for 30 minutes and benzonitrile (4.7 g) was slowly added dropwise so that the inner temperature does not exceed 15C. After stirring at 0C for 90 minutes, lithium diisopropylamide was added dropwise, followed by stirring at 40C for 3 hours. The reaction solution was mixed with ice water, extracted with chloroform, washed with saturated brine, dried and then concentrated. The residue was purified by silica gel column chromatography (chloroform:n-hexane = 20:1) to obtain the objective product (2.2 g).

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

Reference:
Patent; Nippon Shinyaku Co., Ltd.; EP1452525; (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. 87597-21-5, name is Ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., SDS of cas: 87597-21-5

Step B: Preparation of (6,8-dibromoimidazo[1 ,2-a]pyrazin-2-yl)methanolTo a stirred solution of ethyl 6,8-dibromoimidazo[1 ,2-a]pyrazine-2-carboxylate (13.95 g, 40mmol) in toluene (558 mL) at 0 C was added 80 mL DIBAH (120 mmol, 3 eq, 1 .5M in toluene) dropwise. After stirring overnight at rt, the solution was poured on 1M HCl, extracted with ethyl acetate and the organic phase was washed with water, sole, dried over sodium sulphate and filtered. Removal of the solvent and recrystallyzation from DCM yielded 5.55 g (45.2 %) (6,8-dibromoimidazo[1 ,2- a]pyrazin-2-yl)methanol: 1H-NMR (300 MHz, d6-DMSO): delta =8.93 (s, 1 H), 8.05 (s, 1 H), 5.46 (bs, 1 H), 4.63 (s, 2H) ppm. UPLC-MS: RT = 0.73 min; m/z 308.0 [MH+]; required MW = 307.0.

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; BAYER PHARMA AKTIENGESELLSCHAFT; KOPPITZ, Marcus; KLAR, Ulrich; JAUTELAT, Rolf; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; WO2012/80236; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem