Tag: M.W=0-100

2423-65-6, name is Pyrazine 1-oxide, 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. HPLC of Formula: C4H4N2O

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¡ã 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¡ã-305¡ã 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 synthetic route of 2423-65-6 has been constantly updated, and we look forward to future research findings.

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

Application of 5049-61-6, 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 5049-61-6 as follows.

A mixture of 2-aminopyrazin (25 g, 262.9 mmole), chloroacetaldehyde (50% in water, 50 ml, 394 mmole) and NaHCO3 (33.1 g, 394 mmole) was heated for 2 days at 100 C. The reaction mixture was then cooled to RT, satd. K2CO3 solution (100 ml) was added, and the mixture was washed with DCM. The organic phase was dried over Na2SO4 and then concentrated by evaporation to dryness. Purification was carried out by column chromatography on silica gel (DCM/methanol, 95:5+5% NH4OH [35%].

According to the analysis of related databases, 5049-61-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; GRUENENTHAL GmbH; US2009/186899; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 5049-61-6, These common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, 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.

Stage preparation of imidazo[1,2-a]pyrazine A mixture of 34 g (0.2 mol) of bromoacetaldehyde dimethyl acetal, 6,6 ml of concentrated aqueous HBr solution and 28 ml of distilled water is brought to reflux for one hour. After reaction, the mixture is alkalinized and extracted with ether. This organic phase is added to a solution of 19 g (0.2 mol) of aminopyrazine in 50 ml of dimethylformamide (DMF). The ether is removed by distillation and the mixture is maintained with stirring and under a stream of nitrogen for 12 hours. After reaction, the DMF is distilled off; the reaction medium is dissolved in 150 ml of anhydrous ethanol, and then brought to reflux for one hour. The alcohol is then removed by distillation; the residue is dissolved in water, alkalinized with Na2 CO3 and extracted using dichloromethane. After chromatography on a neutral alumina column (eluant =anhydrous ether), 10.7 g (Yld=45%) of imidazo[1,2-a]pyrazine (m.p. 84 C.). are obtained.

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

Reference:
Patent; l’Universite de Montpellier I; US5028605; (1991); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 109-08-0,Some common heterocyclic compound, 109-08-0, name is 2-Methylpyrazine, molecular formula is C5H6N2, 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.

Step a Preparation of n-octyl pyrazine (Compound II in which R=H and n=8) To 15.6 g (0.4 mole) of sodium amide in 400 ml of anhydrous liquid ammonia cooled at -50¡ã C., there were added 37.6 g (0.4 mole) of methyl pyrazine. The mixture was stirred for half an hour at the same temperature. Then, n-heptyl bromide (35.8 g, 0.2 mole), diluted with an equal volume of anhydrous diethyl ether, was added over a 20 minutes period and the mixture was stirred for an additional hour. The reaction was quenched by the addition of 25 g of solid ammonium chloride and the ammonia was replaced by diethyl ether. The mixture was heated until the diethyl ether just started to reflux, and was then poured into ice, rendered strongly acidic by the addition of concentrated HCl and extracted with diethyl ether. The aqueous layer was then rendered basic by the addition of NaOH and extracted with CHCl3. After drying over MgSO4 and filtration, the evaporation of the organic phase led to a residue which was chromatographed on a silica gel column using diethyl ether/petroleum ether (15:85, v:v) as eluent. The title compound II (33.4 g, yield 87percent) was recovered as a pale yellow liquid. IR (film): 3050 (aromatic C-H), 2940, 2860 (C-H), 1580, 1525 (aromatic ring) cm-1. 1 H NMR (60 MHz, CDCl3, HMDS) delta ppm: 8.5 (large s, 3H, aromatic H), 2.75 (t, 2H, CH2 -C=N), 1.7 (m, 2H, CH2 -C-C=N), 1.25 (large s, 10H, (CH2)5), 0.8 (t, 3H, CH3).

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

Reference:
Patent; Societe de Conseils de Recherches et d’Applications Scientifiques (S.C.R.A.S.); US5019576; (1991); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 109-08-0,Some common heterocyclic compound, 109-08-0, name is 2-Methylpyrazine, molecular formula is C5H6N2, 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.

S1:30ml of absolute ethanol,0.2mol / L of 2-methylpyrazine and 1.25mol / L of potassium hydroxide solution into 200mL autoclave,Under 1.5MPa oxygen pressure magnetic stirring 1.5h,Then add 5.0 ¡Á 10-5mol / L of the catalyst was added to the reaction,In the magnetic stirring process,200mL autoclave was heated,And the heating temperature is maintained at 120 ;

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

Reference:
Patent; Henan Engineering College; Zhang Qian; He Li; Li Yue; Chen Lei; Zhao Longtao; (6 pag.)CN106831612; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 2423-65-6, name is Pyrazine 1-oxide, molecular formula is C4H4N2O, 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 2423-65-6

General Procedure 2:; Palladium-Catalyzed Direct Arylation with Aryl Chlorides and Bromides.; To a dried flask was added the diazine N-oxide (1.0 to 3.0 equiv.), K2CO3 (2.0 equiv.), Pd(OAc)2 (5 mol %) and HP(t-Bu)3BF4 (15 mol %). If the arylhalide is a solid, it is added at this point (1.0 equiv.). The flask and its contents were then purged under nitrogen for 10 minutes. If the aryl halide is a liquid, it is added via syringe after purging, followed by the addition of degassed dioxane (to produce a reaction concentration of 0.3 M relative to the halide). The reaction mixture was then heated at 110 C. until the reaction was complete, after which the volatiles were removed under reduced pressure and the residue was purified via silica gel column chromatography.2-Mesitylpyrazine N-oxide (Table 4, Entry 5) Synthesised according to general procedure 2. Purification via silica gel column chromatography using 100% DCM then a mixture of 15% Acetone/DCM gave a beige solid 70% yield with 2 eq. of the N-oxide and 76% yield with 3 eq. of the N-oxide. 1H NMR (300 MHz, CDCl3, 293K, TMS): delta 8.45 (1H, d, J=3.9 Hz) 8.42 (1H, s), 8.26 (1H, d, J=4.2 Hz), 7.00 (2H, s), 2.34 (3H, s), 2.07 (6H, s). 13C NMR (75 MHz, CDCl3, 293K, TMS): 149.4, 146.2, 145.3, 140.0, 137.2, 134.3, 128.5, 125.7, 21.1, 19.4.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2423-65-6, its application will become more common.

Reference:
Patent; University of Ottawa; US2008/132698; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 5049-61-6, These common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, 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.

Sodium nitrite (3.4 g, 50 mmol, 1.3 eq.) was added in small portionsto 98% sulfuric acid (15 mL) ice bath, and the mixture was allowed towarm up and heated to 60. When getting clear, the solution wascooled in an ice bath again. A solution of 2-amino-pyrazine (9) (4 g,39.3 mmol, 1 eq.) in 98% sulfuric acid (15 mL) was added dropwise.The reaction mixture was stirred at 40 for 1 h. After cooling to roomtemperature, it was slowly poured onto crushed ice and stirred until nonitrogen run out. The solution was adjusted to pH 6 with a 40% solutionof sodium hydroxide, resulting in lots of sodium sulfate which wasfiltered off whereafter. The filtrate was extracted with EA (50 mL¡Á3),and the combined organics were dried (Na2SO4), filtered and concentratedin vacuo to give the product as a white precipitate (6.38 g,53%).

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

Reference:
Article; Guo, Shuang; Xu, Mingshuo; Guo, Qi; Zhu, Fuqiang; Jiang, Xiangrui; Xie, Yuanchao; Shen, Jingshan; Bioorganic and Medicinal Chemistry; vol. 27; 5; (2019); p. 748 – 759;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 5049-61-6, The chemical industry reduces the impact on the environment during synthesis 5049-61-6, name is Pyrazin-2-amine, I believe this compound will play a more active role in future production and life.

5, 6 , 7 , 8-tetrahydroimidazo [1, 2-a] pyrazine A29Stage 1. was added to a mixture of 2-aminopyrazin (25 g, 262.9 mmole), chloroacetaldehyde (50% in water, 50 ml, 394 mmole) and NaHCO3 (33.1 g, 394 mmole) and heated for 2 days at 1000C. The reaction mixture was then cooled to RT, saturated K2CO3 solution (100 ml) was added, and the mixture was washed with DCM. The organic phase was dried over sodium sulfate and then concentrated by evaporation to dryness . Purification was carried out by column chromatography on silica gel (DCM / methanol, 95:5 + 5% NH4OH [35%] .

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, Pyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GRUeNENTHAL GMBH; WO2009/90055; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 2423-65-6, The chemical industry reduces the impact on the environment during synthesis 2423-65-6, name is Pyrazine 1-oxide, I believe this compound will play a more active role in future production and life.

1) Take 0.25mmol of pyrazine nitrogen oxide,diphenyl disulfide 0.45mmol,Cu(AcO)2 0.125 mmol and potassium hydroxide 0.5 mmol,add 1 mL of toluene to make a mixture,the mixture was placed in a 5 ml Schlenk tube,heated in an oil bath at 130C,after 48 hours of reaction,cool to room temperature to obtain the reaction solution;2) Concentrate the reaction solution to obtain a concentrate, and use a mixed solvent of ethyl acetate and petroleum ether in a volume ratio of 1:3 as a developing agent, and use silica gel as an adsorbent to perform thin layer chromatography to obtain 16 mg of the target product. The target product yield of this example is 32%, and the target product is subjected to nuclear magnetic characterization.

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, Pyrazine 1-oxide, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Henan Agricultural University; Wu Zhiyong; Zhao Mingqin; Lai Miao; (13 pag.)CN108017581; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4949-13-7, A common heterocyclic compound, 4949-13-7, name is 2-Fluoropyrazine, molecular formula is C4H3FN2, 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: (R)-4-N-Boc-2-methylpiperazine (665 mg, 3.32 mmol), 1-adamantoyl chloride (990 mg, 4.98 mmol), and DIEA (1.15 mL, 6.64 mmol) were dissolved in 2.0 mL of dichloromethane, and the reaction was monitored by LCMS. Upon completion, 5.0 mL of MeOH was added, and the mixture was concentrated in vacuo. The residue was purified by flash chromatography. The purified product was immediately dissolved in 1.0 mL of MeOH and excess 4 N HCl in dioxanes (4.0 mL, 16 mmol). Once the protecting group had cleaved as judged by LCMS, an aqueous solution of saturated sodium bicarbonate was added until the pH was basic. The mixture was extracted with dichloromethane, and the organic layers were concentrated in vacuo to afford 814 mg (94% yield) of adamantan-1-yl((R)-2-methylpiperazin-1-yl)methanone as a white solid. Adamantan-1-yl((R)-2-methylpiperazin-1-yl)methanone (355 mg, 1.35 mmol) and 2-cyano-3-fluoropyridine (1.42 mL, 5.41 mmol) were dissolved in 4.0 mL of NMP in a microwave reaction vial and heated in the microwave for 10 min at 250 C. The reaction mixture was purified via reverse phase chromatography (0.1% TFA in H2O/MeCN). The fractions containing the product were combined and neutralized by the addition of aqueous saturated sodium bicarbonate. The mixture was extracted with dichloromethane, and the organic layers were combined and concentrated in vacuo. The residue was dissolved in 1.0 mL of MeOH and 4 N HCl in dioxanes (3.0 mL, 12 mmol) and stirred for 2 h. The mixture was concentrated in vacuo to afford 212 mgs (39% yield) of the HCl salt as a yellow solid.

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; Lovell, Kimberly M.; Felts, Andrew S.; Rodriguez, Alice L.; Venable, Daryl F.; Cho, Hyekyung P.; Morrison, Ryan D.; Byers, Frank W.; Daniels, J. Scott; Niswender, Colleen M.; Conn, P. Jeffrey; Lindsley, Craig W.; Emmitte, Kyle A.; Bioorganic and Medicinal Chemistry Letters; vol. 23; 13; (2013); p. 3713 – 3718;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem