Category: Pyrazines

These common heterocyclic compound, 6164-79-0, name is Methyl 2-pyrazinecarboxylate, 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. COA of Formula: C6H6N2O2

A solution of the product of Example 83A (6.91 g, 50 mmol) in THF (Aldrich, anhydrous, 150 mL) was cooled down to -78¡ã C. and a solution of LiAlH4 (Aldrich, 1.898 g, 50.0 mmol) in THF (50 mL) was added slowly via an additional funnel. The mixture was stirred at -78¡ã C. under N2 for 1 hour, and then it was then carefully and slowly quenched with HOAc (Aldrich, 10 mL) at -70¡ã C. The mixture was slowly warmed up to ambient temperature and stirred for 10 hours. After being concentrated, the residue was stirred with HCl (2N, 15 mL) in CH2Cl2 (300 mL) for 20 minutes and then filtered through diatomaceous earth to remove solid inorganic salt. The organic filtrate solution was concentrated and the residue was dissolved in EtOAc (100 mL) and filtered through diatomaceous earth again. The organic filtrate solution was concentrated to give the titled compound. 1H NMR (300 MHz, DMSO-d6) delta 8.91 (dd, 1H), 8.94 (d, 1H), 9.12 (d, J=1.6 Hz, 1H), 10.08 (s, 1H) ppm; MS (DCI/NH3) m/z 109 (M+H)+.

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

Reference:
Patent; ABBOTT LABORATORIES; US2009/306096; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 13535-07-4, 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. 13535-07-4, name is 2-Amino-5-ethylpyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Pyridine (1.051 mL, 12.99 mmol) was added dropwise to a stirred solution of phenyl carbonochloridate (1.324 mL, 10.56 mmol) in dichloromethane (DCM) (20 ml) at room temperature and stirred for 30 minutes. Then 5-ethylpyrazin-2-amine (1 g, 8.12 mmol) dissolved in dichloromethane (DCM) (10 ml) was added dropwise at room temperature and stirred at 50 C for 16 h. Allowed the reaction mixture to room temperature, diluted with DCM (3X50 mL), washed with water (2X30 mL) and brine (30 mL). Separated the organic layer and dried over sodium sulfate, filtered and concentrated. Residue was purified by column chromatography using silica gel (100-200 mesh) by 10% ethyl acetate in pet ether as eluent to get desired product as off white fluffy solid (1.6 g, 6.58 mmol, 81%), LCMS (m/z) 244.2 (M+H)+.

The chemical industry reduces the impact on the environment during synthesis 2-Amino-5-ethylpyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO.2) LIMITED; ELLIS, James Lamond; EVANS, Karen Anderson; FOX, Ryan Michael; MILLER, William Henry; SEEFELD, Mark Andrew; (766 pag.)WO2016/79709; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 939412-86-9, 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. 939412-86-9 name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, 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.

HATU (15.91 g, 41.8 mmol) was added to a stirred, cooled 0 C mixture of (6R,8aS)-3-oxooctahydroindolizine-6-carboxylic acid (7.3 g, 39.8 mmol), (3- chloropyrazin-2-yl)methanamine hydrochloride (7.89 g, 43.8 mmol) and DIPEA (10.44 ml, 59.8 mmol) in CH2C12 (25 ml) and the mixture was stirred at room temperature for 1 h. and then concentrated. The residue was purified by column chromatography on silica gel (Isco 240 g silica gel), eluting with CH2Cl2/MeOH (50/1) to give (6R,8aS)-N- ((3-chloropyrazin-2-yl)methyl)-3-oxooctahydroindolizine -6-carboxamide (11.15g, 36.1 mmol, 91 % yield) as a white solid. LC-MS: Ret. time 1.09 min; m/z 309.11 (M+H)+; 1HNMR (CDCI3, 500 Hz): 8.38 (1H, d, J = 2 Hz), 8.25 (1H, d, J = 2 Hz), 7.37 (1H, dd, J = 4 and 4.5 Hz), 4.56-4.72 (2H, m,l), 4.29 (1H, dd, J = 13 and 4.5 Hz),3.42-3.47 (m,l), 2.81 (1H, t, J = 13 Hz), 2.35 (2H, t, J = 8 Hz), 2.17-2.23 (1H, m), 2.04 (1H, d, J = 13.5 Hz), 1.94-1.96 (1H, m), 1.74-1.82 (1H, m), 1.55-1.62 (1H, m), 1.16-1.24 (1H, m).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, (3-Chloropyrazin-2-yl)methanamine hydrochloride, and friends who are interested can also refer to it.

Reference:
Patent; MERCK SHARP & DOHME CORP.; WU, Hao; KIM, Ronald M.; LIU, Jian; GAO, Xiaolei; BOGA, Sobhana Babu; GUIADEEN, Deodialsingh; KOZLOWSKI, Joseph; YU, Wensheng; ANAND, Rajan; YU, Younong; SELYUTIN, Oleg B.; GAO, Ying-Duo; LIU, Shilan; YANG, Chundao; WANG, Hongjian; WO2014/114185; (2014); A1;,
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 21279-62-9 as follows. Product Details of 21279-62-9

General procedure: The starting compound (1.27 mmol) was treated with 18 aliphatic amines, alicyclic amines or saturated heterocycles containing at least one nitrogen atom (2.54 mmol). Four reactions were completed by conventional heating methods. The conditions were 110 C, toluene as a solvent and pyridine (1.27 mmol) as a base. The reaction time was set to one hour. Then the reactions were completed using the microwave reactor with focused field and conditions used for syntheses were 140 C, 30 min,120 W, methanol used as a solvent and pyridine (1.27 mmol) as a base. They were set experimentally with respect to prior experience. The progress of reaction was monitored with TLC in system hexane/ethyl acetate (1:1). Then the mixture was separated by flash column chromatograph using gradient elution. Mobile phases were hexane and ethyl acetate again.

According to the analysis of related databases, 21279-62-9, the application of this compound in the production field has become more and more popular.

Reference:
Article; Jandourek, Ondrej; Dolezal, Martin; Kunes, Jiri; Kubicek, Vladimir; Paterova, Pavla; Pesko, Matus; Buchta, Vladimir; Kralova, Katarina; Zitko, Jan; Molecules; vol. 19; 7; (2014); p. 9318 – 9338;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 38557-72-1, These common heterocyclic compound, 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, 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.

First, into a recovery flask equipped with a reflux pipe were put 2.05 g of 2-chloro-3,5-dimethylpyrazine, 2.48 g of 1-naphthylboronic acid, 1.53 g of sodium carbonate, 0.066 g of bis(triphenylphosphine)palladium(II)dichloride (abbreviation: Pd(PPh3)2Cl2), 15 mL of water, and 15 mL of acetonitrile, and the air in the flask was replaced with argon. This reaction container was subjected to irradiation with microwaves (2.45 GHz, 100 W) for 10 minutes, whereby heating was performed. After that, water was added to this solution, and an organic layer was extracted with dichloromethane. The obtained organic layer was washed with water and dried with magnesium sulfate. After the drying, the solution was filtered. The solvent of this solution was distilled off, and then the obtained residue was purified by silica gel column chromatography using dichloromethane as a developing solvent. Accordingly, Hdm1npr (a light orange powder, 59% yield), which was the substance to be produced, was obtained. Note that the irradiation with microwaves was performed using a microwaves synthesis system (Discover, produced by CEM Corporation). The synthesis scheme of Step 1 is shown in (a-1) below.

The synthetic route of 38557-72-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Semiconductor Energy Laboratory Co., Ltd.; US2011/82296; (2011); A1;,
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

Electric Literature of 21948-70-9, A common heterocyclic compound, 21948-70-9, name is 2-Methylthiopyrazine, molecular formula is C5H6N2S, 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.

To a stirred solution of 2-(Methylthio)Pyrazine (0.013 g,0.10 mmol) in 5 mL of methanol, AgPF6 (0.051 g, 0.20 mmol) was added. Just after addition a white precipitate was formed and the reaction mixture was stirred for 30 min. The precipitate collectedand dried under vacuum. The white powder was dissolved in acetonitrileand kept for crystallization in dark. After few days colourlessrod shape crystals suitable for single crystal X-ray diffractionwere obtained. Yield: 0.059 g (79%). Anal. Calc. for C5H6N2F6PSAg:C, 15.85; H, 1.60; N, 7.39, Found: C, 15.52; H, 1.54; N, 8.03%. IR(KBr, cm1): 3067 (w), 2996 (w), 2924 (w), 1635 (w), 1507 (m),1468 (m), 1383 (m), 1299 (w), 1137 (s), 1046 (m), 1002 (m), 827(s), 561 (s). 1H NMR (DMSO, dppm): 2.53 (Me), 8.29, 8.47, 8.57(pyrazine ring). 13C NMR (DMSO, dppm): 12.68 (Me), 140.14,143.32, 144.83, 157.37 (pyrazine ring).

The synthetic route of 21948-70-9 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Singh, Suryabhan; Raghuvanshi, Abhinav; Mathur, Pradeep; Singh, Amrendra K.; Polyhedron; vol. 169; (2019); p. 8 – 13;,
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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., Recommanded Product: 16298-03-6

1.5 equivalents of N-iodosuccinimide are added at room temperature to 5 g (32.7 mmol) of a methyl 3-aminopyrazine-2-carboxylate solution in 25 ml of dimethylformamide. The reaction medium is heated at 65C for 1 hour, added together with 0.5 equivalents of N-iodosuccinimide and maintained at 65C for 24 hours. After returning to room temperature, the solvent is evaporated and then the product is extracted several times with dichloromethane. The organic phases are combined, washed with 10% sodium bisulfite solution, dried on magnesium sulfate and concentrated to yield 8 g (88%) of methyl 3-amino-6-iodopyrazine-2-carboxylate in the form of a yellow solid. LCMS (EI, m/z): (M+1) 280 1H NMR: deltaH ppm (400 MHz, DMSO): 8.50 (1H, s, CHarom), 7.50 (2H, bs, NH2), 3.20 (3H, s, CH3)

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 16298-03-6.

Reference:
Patent; PIERRE FABRE MEDICAMENT; Kruczynski, Anna; Creancier, Laurent; Kaloun, El Bachir; Bedjeguelal, Karim; Rabot, Remi; EP2689779; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4858-85-9, These common heterocyclic compound, 4858-85-9, name is 2,3-Dichloropyrazine, 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.

To a solution of 2,3-dichloropyrazine (5) (2000mg, 13.42mmol) LHMDS (6.0ml, 30.87mmol) (1M in THF) under nitrogen condition was added dropwise a soution of ethyl acetate (1.44ml, 14.76mmol) in toluene (20ml) .The reaction mixture was stirred at room temperature for 24 h. Then, the reaction mixture was diluted with Et2O and was quenched with saturated aq. NH4Cl. The two layers were separated and the aq. one was further extracted with Et2O. The combined organic layers were washed with brine, dried over MgSO4 and concentrated in vacuo. The crude was then purified by flash column chromatography (EtOAc/Heptane, 15:85). The desired fractions were concentrated to dryness in vacuo to afford 3 (1850mg, 8.76mmol, 65%) as a pale yellow oil.

Statistics shows that 2,3-Dichloropyrazine is playing an increasingly important role. we look forward to future research findings about 4858-85-9.

Reference:
Article; Luise, Nicola; Wyatt, Paul G.; Bioorganic and Medicinal Chemistry Letters; vol. 29; 2; (2019); p. 248 – 251;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 6705-33-5, 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. 6705-33-5, name is Pyrazin-2-ylmethanol belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Pyrazin-2-ylmethanol (103 mg, 0.094 mmol) and thionyl chloride (546 mg, 4.59 mmol) were dissolved inDichloromethane (15 mL) and reacted for 3 h. The reaction mixture was poured into water (30 mL), extracted with ethyl acetate (30 mL ¡Á 3), and saturated saltWashed with water (15 mL) and dried over anhydrous sodium sulfate. The solvent was removed and the residue was subjected to column chromatography (eluent: PE / EtOAc (v / v)= 10/1) to obtain 87 mg of a pale yellow oil, yield: 72.34%.

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

Reference:
Patent; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Liu Bing; Bai Shun; Zhou Youbo; Yang Tiping; He Wei; Zhang Yingjun; Zheng Changchun; (103 pag.)CN106749268; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem