Author: Jessica.F

Application of 345311-03-7, The chemical industry reduces the impact on the environment during synthesis 345311-03-7, name is tert-Butyl 5,6-dihydroimidazo[1,2-a]pyrazine-7(8H)-carboxylate, I believe this compound will play a more active role in future production and life.

1 ,1-Dimethylethyl 5,6-dihydroimidazo[1 ,2-a]pyrazine-7(8/-/)-carboxylate (118) (1.563 g, 7 mmol) and NCS (0.935 g, 7.00 mmol) were heated at 80 0C for 2 h in toluene (30 ml_). The solvents were removed in vacuo and the residue was purified by flash chromatography (Isolera, 50 g, 0-100% ethyl acetate/iso-hexane) to afford product in 1.55 g. LC/MS = 258/260 (M+H)+, retention time = 0.64 minutes (2 minute method).

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, tert-Butyl 5,6-dihydroimidazo[1,2-a]pyrazine-7(8H)-carboxylate, other downstream synthetic routes, hurry up and to see.

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

Reference of 5900-13-0, The chemical industry reduces the impact on the environment during synthesis 5900-13-0, name is 5-Bromo-3-methoxypyrazin-2-amine, I believe this compound will play a more active role in future production and life.

General procedure: Azaheteroaryl halide (1 mmol), catalyst (0.005-0.05 mol %) and 1M aq. Na2CO3 (1.1 mL) were stirred in a mixture of H2O-EtOH(1:2, 5 mL). The arylboronic acid (1.1 mmol) was added to the above mixture and stirring was continued for required time at 60 C. After the requisite time, reaction mixture was diluted with ethyl acetate and the catalyst was separated by centrifugation. The centrifugate was dried over anhydrous sodium sulphate and evaporated. Then the product was analyzed by GC-MS or LC-MS.The solution was concentrated and chromatographed on a silicagel column with n-hexane-ethyl acetate (4:1) as the eluting solvent to give the coupled product. The product was confirmed by 1H and 13C NMR spectral analysis. The used catalyst was washed with water, ethanol and dichloromethane, and dried under vacuum before reuse.

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, 5-Bromo-3-methoxypyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Ganesamoorthy; Muthu Tamizh; Shanmugasundaram; Karvembu; Journal of Organometallic Chemistry; vol. 862; (2018); p. 76 – 85;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

33332-28-4, name is 2-Amino-6-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. Quality Control of 2-Amino-6-chloropyrazine

4. 2-Chloro-3-bromo-6-aminopyrazine and 2-amino-3-bromo-6-chloropyrazine A solution of 2-chloro-6-aminopyrazine (20 g, 0.15 mole) in chloroform (1940 ml) was stirred at -5¡ã C. to 0¡ã C. N-Bromosuccinimide (27.58 g, 0.15 mole) was added in portions maintaining the temperature between -5 and 0¡ã C. The mixture was warmed to room temperature and stirred for 3.50 hrs. The mixture was then washed with aqueous saturated sodium bicarbonate (1*300 ml), then water (1*500 ml), dried over anhydrous magnesium sulphate, filtered and the filtrate evaporated down in vacuo. The residue was purified by ‘flash chromatography’ using chloroform as the eluent. Yield of 2-chloro-3-bromo-6-aminopyrazine 13.89 g (43percent), M.p. 146-147¡ã C. Yield of 2-amino-3-bromo-6-chloropyrazine 4.90 g (15percent), M.p. 124-125¡ã C.

The synthetic route of 33332-28-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Glaxo Wellcome, Inc.; US6255307; (2001); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 91476-80-1, 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. 91476-80-1, name is 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows.

A mixture of 150 mg (0.28 mmol) of 2-[(3R)-3-methylmorpholin-4-yl]-8-[1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-5-yl]-1,7-naphthyridin-4-yl trifluoromethanesulfonate and 119 mg (0.97 mmol) 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine in 0.42 ml of MeCN was stirred at 70C for 48 h under argon. After cooling the reaction mixture was diluted with ethyl acetate and THE and washed with saturated aqueous sodium chloride solution. The organic phase was filtered using a Whatmanfilter and then concentrated to give the crude product that was used without further purification in the next step.

The chemical industry reduces the impact on the environment during synthesis 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; WORTMANN, Lars; LUeCKING, Ulrich; LEFRANC, Julien; BRIEM, Hans; KOPPITZ, Marcus; EIS, Knut; VON NUSSBAUM, Franz; BADER, Benjamin; WENGNER, Antje Margret; SIEMEISTER, Gerhard; BONE, Wilhelm; LIENAU, Philip; GRUDZINSKA-GOEBEL, Joanna; MOOSMAYER, Dieter; EBERSPAeCHER, Uwe; SCHICK, Hans; (509 pag.)WO2016/20320; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 5424-01-1, 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. 5424-01-1, name is 3-Aminopyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows.

Compound 1 (5 g, leq) was added to methanol (50 ml)Ice water bath by adding concentrated sulfuric acid (4eq),The reaction was stirred at room temperature,TLC showed complete reaction,concentrate,Saturated sodium carbonate adjusted to pH = 8,Filter, 50 dry 2h,A brown solid 2 (4.18 g,76%).

The chemical industry reduces the impact on the environment during synthesis 3-Aminopyrazine-2-carboxylic acid. I believe this compound will play a more active role in future production and life.

Reference:
Patent; Central South University; Liu Fengliang; Li Cuiqin; (19 pag.)CN106866553; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 33332-25-1, 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. 33332-25-1 name is Methyl 5-chloropyrazine-2-carboxylate, 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.

Combine 5-CHLOROPYRAZINE-2-CARBOXYLIC acid methyl ester (626 mg, 3.64 mmol), phenylboronic acid (666 mg, 5.45 mmol), cesium fluoride (55 mg, 0.36 mmol) and NA2CO3 (964 mg, 9.09 mmol) in DMF (5 mL) and water (5 mL) with stirring. Place the hetereogeneous reaction mixture, open to the air, in an oil bath maintained at 80C. After 5 minutes of heating, add Pd (OAC) 2 (81 mg 0.36 mmol) in one portion and stir until reaction turns black. Cool the reaction to room temperature, dilute with ethyl acetate, and filter through a short plug of celite with additional ethyl acetate. Wash the organics with water, dry over MGS04, filter and evaporate. Purification by flash column chromatography yields 2-phenylpyrimidine-5-carboxylic acid methyl ester as a yellow solid. Dissolve the purified ester in THF (0.25M) and add an equal volume of 1M NAOH. Stir vigorously at room temperature for 15 hours. Upon completion, acidify the reaction with conc. HCI and extract with ethyl acetate. Evaporation of the solvent yields 63 mg (8%) of the title COMPOUND. H NMR (DMSO): 9.37 (s, 1H), 9.21 (s, 1H), 8.23-8. 21 (m, 2H), 7.57-7. 77 (m, 3H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Methyl 5-chloropyrazine-2-carboxylate, and friends who are interested can also refer to it.

Reference:
Patent; ELI LILLY AND COMPANY; WO2004/94382; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 13515-06-5,Some common heterocyclic compound, 13515-06-5, name is 5,6-Dimethylpyrazine-2-carboxylic acid, molecular formula is C7H8N2O2, 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.

5,6-dimethylpyrazine acid (248 mg, about 2 mmol, prepared as Example 2), 4-chloro-1-butanol (2.4mmol), EDCI (2.4mmol) and DMAP (0.2mmol) were added to dry methylene chloride (20mL), stir at room temperature for 12 hours, then dilute with dichloromethane (20mL), The saturated aqueous NaCl solution was washed, dried over anhydrous sodium sulfate, and purified by column chromatography to obtain an oily liquid. The hederagenin(236mg, 0.5mmol), K2CO3 (207mg, 1.5mmol) and oily liquid were added to DMF (20mL), The mixture was stirred at 85 C for 4 hours. It was then diluted with ethyl acetate (20 mL), washed with saturated aqueous NaCl solution, dried over anhydrous sodium sulfate, concentrated and purified by column chromatography to obtain a white powder, H-17. Yield: 27% (after chromatograph with DCM / MeOH, 1% -2%) as a white powder, m.p .: 134.7 C.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5,6-Dimethylpyrazine-2-carboxylic acid, its application will become more common.

Reference:
Patent; Xinhuo Zhiyao (Beijing) Technology Co., Ltd.; Fang Kang; Guo Wenbo; Wang Penglong; Cheng Gang; (26 pag.)CN110964078; (2020); A;,
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. 91476-80-1, name is 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows., Safety of 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine

Example 32 (5,6-Dihydro-8H-imidazo[1,2-a]pyrazin-7-yl)-(4-{4-[4-(3-methanesulfonyl-propoxy)-indol-1-yl]-pyrimidin-2-ylamino}-cyclohexyl)-methanone A mixture of sodium 4-{4-[4-(3-methanesulfonyl-propoxy)-indol-1-yl]-pyrimidin-2-ylamino}-cyclohexanecarboxylate (0.3 g) and 5,6,7,8-tetrahydro-imidazo[1,2-a]pyrazine (0.24 g). HBTu (0.4 g), DIEA (1 mL), THF (3 mL) and DMA (3 mL) was stirred at room temperature for three hours. The reaction mixture was then partitioned between EtOAc and water, the organic layer washed with saturated NaHCO3 and water, dried over Na2SO4 and concentrated in vacuo. The residue was purified via prep. TLC (10% MeOH/DCM) to give 56 mg of (5,6-dihydro-8H-imidazo[1,2-a]pyrazin-7-yl)-(4-{4-[4-(3-methanesulfonyl-propoxy)-indol-1-yl]-pyrimidin-2-ylamino}-cyclohexyl)-methanone. MS (M+H)=578.

According to the analysis of related databases, 91476-80-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Gong, Leyi; Tan, Yun-Chou; US2011/301170; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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