Pyrazines

Synthetic Route of 1174321-06-2, These common heterocyclic compound, 1174321-06-2, name is 5-(Difluoromethyl)pyrazine-2-carboxylic acid, 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 tert-butyl 4-aminopiperazine-l-carboxylate (578 mg, 2.8 mmol, 1.0 equiv) in DMF (05 mL) was added HATU (2128 mg, 5.6 mmol, 2.0 equiv) at RT and stirred for 10 minutes. Then 5-(difluoromethyl)pyrazine-2-carboxylic acid (500 mg, 2.8 mmol, 1.0 equiv) was added followed by the addition of DIPEA (1.5 mL, 8.4 mmol, 3.0 equiv). The resulting reaction mixture was allowed to stir at RT for ovemigiit. Product formation was confirmed by LCMS. the reaction mixture was diluted with water (50 mL) and extracted with EtOAc (50 mL c 2). The combined organic layer was washed with water (30mL), brine solution (30 mL x 2), dried over anhydrous sodium sulfate and concentrated under reduced pressure, to obtain tert-butyl 4-(5-(difluoromethyl)pyrazine-2-carboxamido)piperazine-l -carboxylate (400 mg, 39 % Yield) as a brown solid. LCMS 358.2 [ M i l : NMR (400 MHz, DMSCWe) d 10.13 (s, 1 H), 9.24 (s, 1 H), 8.99 is. 1 H), 3.34 – 3.49 (m, 4 H), 2.84 (t, .7=5.04 Hz, 4 H), 1.41 (s, 9H).

The synthetic route of 1174321-06-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; PRAXIS BIOTECH LLC; DELGADO OYARZO, Luz Marina; URETA DIAZ, Gonzalo Andres; PUJALA, Brahmam; PANPATIL, Dayanand; BERNALES, Sebastian; CHAKRAVARTY, Sarvajit; (0 pag.)WO2019/236710; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 1379338-74-5, 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. 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

5,7-dichloropyrido[4,3-b]pyrazine (3.6 g, 18 mmol) and DIPEA (2.8 g, 21.6 mmol) was added to a solution of tert-butyl tert-butyl 3-(aminomethyl)-4-(tert-butyldimethylsilyloxy)piperidine-1-carboxylate (6.2 g, 18 mmol) in THF (20 mL) and the mixture was refluxed overnight. The volatile components were evaporated and the residue was extracted with ethyl acetate. Ethyl acetate was washed with brine and dried. The solvent was removed and the residue was re-dissolved in THF (16 mL) and TBAF was added in. The reaction mixture was stirred at room temperature for 2 hours. The mixture was diluted with ethyl acetate, washed with brine, then dried, filtered, and concentrated in vacuo. The crude residue was purified by flash chromatography to give the title compound (3.35 g, 47% yield). MS (m/z): 394 (M+H)+.

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, 5,7-Dichloropyrido[3,4-b]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; HUTCHISON MEDIPHARMA LIMITED; Su, Wei-Guo; Deng, Wei; Ji, Jianguo; US2014/121200; (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 21948-70-9 as follows. Product Details of 21948-70-9

General procedure: 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) wasadded. Just after addition a white precipitate was formed and thereaction 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).

According to the analysis of related databases, 21948-70-9, the application of this compound in the production field has become more and more popular.

Reference:
Article; Singh, Suryabhan; Raghuvanshi, Abhinav; Mathur, Pradeep; Singh, Amrendra K.; Polyhedron; vol. 169; (2019); p. 8 – 13;,
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Application of 38557-72-1, 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. 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Example 2Synthesis Example 2Example 2 gives a specific example of the synthesis of the organometallic complex represented by the structural formula (130) in Embodiment 1 which is one embodiment of the present invention, tris[3,5-dimethyl-2-(4-phenoxyphenyl)pyrazinato]iridium(III) (abbreviation: [Ir(dmpoppr)3]). A structure of [Ir(dmpoppr)3] is illustrated below. Synthesis of Tris[3,5-dimethyl-2-(4-phenoxyphenyl)pyrazinato]iridium(III) (abbreviation: [Ir(dmpoppr)3])First, 1.42 g of the ligand prepared in Step 1 in Synthesis Example 1 above, Hdmpoppr, and 0.50 g of tris(acetylacetonato)iridium(III) were placed into a reaction container provided with a three-way cock, and the air in the reaction container was replaced with argon. After that, the mixture was heated at 250 C. for 43 hours to be reacted. The reactant was dissolved in dichloromethane, and this solution was filtered. After the solvent of the filtrate was distilled and the obtained residue was washed with ethyl acetate and then with methanol, recrystallization from dichloromethane gave the organometallic complex which is one embodiment of the present invention, [Ir(dmpoppr)3] (an orange powder in a yield of 22%). The synthesis scheme is illustrated in the following formulae (f). The results of the nuclear magnetic resonance (1H NMR) spectroscopy, by which the orange powder obtained above was analyzed, are shown below. In addition, a 1H-NMR chart is shown in FIG. 12. These results revealed that the organometallic complex represented by the above-described structural formula (130) which is one embodiment of the present invention, [Ir(dmpoppr)3], was obtained in Synthesis Example 2.1H NMR. delta (CDCl3): 2.38 (s, 9H), 2.97 (s, 9H), 6.31 (d, 3H), 6.47 (dd, 3H), 6.82 (d, 6H), 7.02 (t, 3H), 7.15 (s, 3H), 7.21 (t, 6H), 7.81 (d, 3H).Next, an ultraviolet-visible absorption spectrum (hereinafter, simply referred to as an ?absorption spectrum?) of a dichloromethane solution of [Ir(dmpoppr)3] and an emission spectrum thereof were measured. The measurement of the absorption spectrum was conducted at room temperature, for which an ultraviolet-visible light spectrophotometer (V550 type manufactured by Japan Spectroscopy Corporation) was used and the dichloromethane solution (0.083 mmol/L) was put in a quartz cell. In addition, the measurement of the emission spectrum was conducted at room temperature, for which a fluorescence spectrophotometer (FS920 manufactured by Hamamatsu Photonics Corporation) was used and the degassed dichloromethane solution (0.50 mmol/L) was put in a quartz cell. Measurement results of the obtained absorption and emission spectra are shown in FIG. 13, in which the horizontal axis represents wavelength and the vertical axis represents absorption intensity and emission intensity. In FIG. 13 where there are two solid lines, the thin line represents the absorption spectrum and the thick line represents the emission spectrum. Note that the absorption spectrum in FIG. 13 is the results obtained in such a way that the absorption spectrum measured by putting only dichloromethane in a quartz cell was subtracted from the absorption spectrum measured by putting the dichloromethane solution (0.083 mmol/L) in a quartz cell.As shown in FIG. 13, the organometallic complex of one embodiment of the present invention, [Ir(dmpoppr)3], has an emission peak at 561 nm, and yellow light emission was observed from the dichloromethane solution.

The chemical industry reduces the impact on the environment during synthesis 2-Chloro-3,5-dimethylpyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; Semiconductor Energy Laboratory Co., Ltd.; US2012/95226; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 6966-01-4, 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. 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, This compound has unique chemical properties. The synthetic route is as follows.

. Step 2: 3-Amino-6-bromopyrazine-2-carboxylic acid[00140] A mixture of methyl 3-amino-6-bromo-pyrazine-2-carboxylate (5.1 1 g, 22.02 mmol) and lithium hydroxide (2.637 g, 110.1 mmol) in MeOH (20 mL) and Iota¾0 (20 mL) was heated to 90 C for 2 hours. The reaction mixture was allowed to cool and neutralized with HCl and the resultant precipitate collected by filtration. The sub-title product was taken on to the next step without further purification (4.80g, 99% Yield).

The chemical industry reduces the impact on the environment during synthesis Methyl 3-amino-6-bromopyrazine-2-carboxylate. I believe this compound will play a more active role in future production and life.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-Damien; DURRANT, Steven, John; KNEGTEL, Ronald, Marcellus, Alphonsus; O’DONNELL, Michael; REAPER, Philip, Michael; WO2011/143419; (2011); A1;,
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Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 75907-74-3, name is (3,5,6-Trimethylpyrazin-2-yl)methanol, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 75907-74-3, Product Details of 75907-74-3

To a stirred, cooled (0C) solution of (3,5,6-trimethylpyrazin-2-yl)methanol (0.3 g, 1.97 mmol) in dichloromethane (5 ml) under an argon atmosphere was added dropwise a solution of thionyl chloride (469 mg, 286 mu, 3.94 mmol) in 2 ml CH2CI2. When the addition was complete, the ice bath was removed and stirring at r.t. was continued for 2 hrs. The mixture was concentrated to dryness to leave the crude product as a light red solid (417 mg) which was used in the next step without further purification. MS: M = 171.1 (M+H)+

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, (3,5,6-Trimethylpyrazin-2-yl)methanol, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; HOFFMANN-LA ROCHE INC.; FLOHR, Alexander; GROEBKE ZBINDEN, Katrin; KOERNER, Matthias; LERNER, Christian; WO2013/178569; (2013); 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. 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., HPLC of Formula: C5H3ClN2O2

A solution of 5-chloro-pyrazine-2-carboxylic acid (1.5 g, 9.46 mmol) in dry dimethylsulphoxide (5 ml) was treated with cyclopropyl-methanol (1.15 ml, 14.1 mmol) and powdered potassium hydroxide (2.12 g, 37.8 mmol). The mixture was irradiated in a microwave vessel at 80 C for 45 minutes. In order to complete the transformation the irradiation was continued for another 45 minutes at 80 C. For the workup, the reaction mixture was quenched with a solution of citric acid (10%), then extracted with ethyl acetate (5×30 ml) followed by a 20:80-mixture of methanol and dichloromethane (200 ml). The combined organic layers were dried over sodium sulphate, evaporated at reduced pressure and, finally, lyophilized to remove residual dimethylsulphoxide. Further purification by flash chromatography on silica gel yielded the 5-cyclopropylmethoxy-pyrazine-2-carboxylic acid as an off-white solid (1.83 g, 27% of theory). MS (ISP): m z = 195 [M+H]+

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; F. HOFFMANN-LA ROCHE AG; SIENA BIOTECH S.P.A.; BANNER, David; GUBA, Wolfgang; HILPERT, Hans; MAUSER, Harald; MAYWEG, Alexander, V.; NARQUIZIAN, Robert; PINARD, Emmanuel; POWER, Eoin; ROGERS-EVANS, Mark; WOLTERING, Thomas; WOSTL, Wolfgang; WO2011/69934; (2011); 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 87597-21-5 as follows. Safety of Ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylate

To a stirred solution of ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylate (13.95 g, 40 mmol) 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, 1H), 8.05 (s, 1H), 5.46 (bs, 1H), 4.63 (s, 2H) ppm. UPLC-MS: RT=0.73 min; m/z 308.0 [MH+]; required MW=307.0.

According to the analysis of related databases, 87597-21-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; BAYER INTELLECTUAL PROPERTY GMBH; Koppitz, Marcus; Klar, Ulrich; Jautelat, Rolf; Kosemund, Dirk; Bohlmann, Rolf; Bader, Benjamin; Lienau, Philip; Siemeister, Gerhard; US2013/281460; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 24241-18-7, The chemical industry reduces the impact on the environment during synthesis 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, I believe this compound will play a more active role in future production and life.

(a) Add 2-amino-3,5-dibromopyrazine (10 g, 39.54 mmol, 1 eq) to a 100 mL autoclaveAnd ammonia (50 mL, commercially available),Raise the temperature to 130 C under nitrogen protection conditions and carry out the reaction overnight (10 to 12 hours);Cooling, suction filtration,The obtained solid was vacuum dried to give 5.0 g of Compound II.

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-Amino-3,5-dibromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Suzhou Derivative Biological Technology Co., Ltd.; Liu Ke; (6 pag.)CN108395436; (2018); 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.

To a solution of 2-aminopyrazine (2.0 g, 21.03 mmol) in ethanol (40 mL) was added 2-bromo-1,1-dimethoxyethane (2.5 mL, 21.03 mmol) followed by 5 drops of concentrated hydrochloric acid. After refluxing for 14 hours, the solvent was evaporated. The residue was partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution. The aqueous layer was extracted with ethyl acetate (3×). The combined organic phase was washed with brine, dried over magnesium sulfate, and concentrated. The residue was purified by flash chromatography (100% ethyl acetate, 10% methanol in ethyl acetate, then 10% methanol in dichloromethane) to give 536 mg of the title compound as a solid. 1H NMR (500 MHz, CDCl3) delta 7.70 (bs, 1H), 7.82 (bs, 1H), 7.89 (d, 1H, J=4.4 Hz), 8.10 (d, 1H, J=4.6 Hz), 9.12 (s, 1H)

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; Merck Sharp & Dohme Corp.; Edmondson, Scott D.; Fisher, Michael H.; Kim, Dooseop; Maccoss, Malcolm; Parmee, Emma R.; Weber, Ann E.; Xu, Jinyou; US2015/359793; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem