Tag: M.W=100-200

Adding a certain compound to certain chemical reactions, such as: 69214-33-1, name is 8-Chloroimidazo[1,2-a]pyrazine, 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 69214-33-1, Quality Control of 8-Chloroimidazo[1,2-a]pyrazine

To the solution of compound 9 (6.47 g, 42.13 mmol) indichloromethane (140 ml) N-bromosuccinimide (7.50 g,42.13 mmol) was added and the mixture was stirred at roomtemperature for 3 h. The reaction mixture was diluted withdichloromethane and stirred with 10% aqueous sodium carbonatesolution for 1 h before the layers were separated. The organic layerwas washed with water (2), dried over sodium sulphate, filteredand concentrated under reduced pressure. The crude product was triturated with diisopropyl ether and filtered to give the titlecompound (14.40 g)

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Article; Garamvoelgyi, Rita; Dobos, Judit; Sipos, Anna; Boros, Sandor; Illyes, Eszter; Baska, Ferenc; Kekesi, Laszlo; Szabadkai, Istvan; Szantai-Kis, Csaba; Keri, Gyoergy; Oerfi, Laszlo; European Journal of Medicinal Chemistry; vol. 108; (2016); p. 623 – 643;,
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. 123-32-0, name is 2,5-Dimethylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C6H8N2

1), in 125 ml in the reaction bottle, by adding 1.08g (10mmol) 2, 5-dimethyl-pyrazine, 1.13g (4mol) FeSO4¡¤ 7H2O, by adding 30 ml of water (i.e., 3 ml/1mmol), stirring in the ice bath, then measure 0.1mol (6 ml) 98% concentrated sulfuric acid to constant pressure dropping funnel slowly dropping, the temperature change in the process of dropping the attention, to maintain the temperature of the reaction bottle too high (i.e., to control the temperature to 60 C the following can be). After concentrated sulfuric acid instillment , on a rectifier 22mmol (7.5 ml) hydrogen peroxide, PV drop instillment , and to continue the reaction in the ice bath, dripping at any time in the process of observing reaction bottle temperature change (i.e., to control the temperature to 60 C the following can be). After dripping adding 240uL (3mmol) is propionaldehyde, slowly elevated temperature so as to control the temperature to 50-60C, in the reaction 1h, 2h, 3h, 4h are respectively adding 240uL is propionaldehyde. In the reaction process and reaction conditions for TLC, reaction conditions estimated raw material, when the raw material after the reaction is complete can stop the reaction (about 6h).2), stop heating after the reaction, cooling to room temperature, with 30 ml ethyl acetate extraction, the aqueous phase (the lower) the quality of the diluted for the fraction of 20% NaOH to adjust the pH to 8, in the process the alkali adjusting full stirring, not to allow the temperature of the solution is too high (i.e., not to exceed 60 C). Then extracting with ethyl acetate three times, combined with the phase (the upper), pressure-reducing (pressure -0.08–0.10 MPa) concentrated to dry, yellow oily substance is about 1.532 g. Finally through the column chromatography the 2-ethyl -3, 6-dimethyl-pyrazine separated.As follows:The silica gel chromatography (built-in 200-300 purpose silica gel 30g), the resulting 1.532g for column chromatography yellow oily substance; for the mobile phase ethyl acetate: petroleum ether = 1:20 of the mixed solution, the total consumption of mobile phase about 500 ml; final 1.245g product—2-ethyl -3, 6-dimethyl-pyrazine (the purity is 95.6%). Yield 90.88%.

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 123-32-0.

Reference:
Patent; Zhejiang University; Cheng, Jingli; Wang, Likun; Zhao, Yang; Zhao, Jinhao; (9 pag.)CN105237486; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 14508-49-7, name is 2-Chloropyrazine, 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. Safety of 2-Chloropyrazine

Step 1: tert-Butyl 4-(pyrazin-2-yl)piperazine-1-carboxylate Into a 1 L flask equipped with a condenser and a magnetic stir bar was added 2-chloropyrazine (20.6 g, 180 mmol), tert-butyl piperazine-1-carboxylate (33.5 g, 180 mmol), potassium carbonate (29.8 g, 216 mmol), dioxane (225 mL) and DMF (225 mL). The mixture was heated to 120 C. for 3 days. The mixture was cooled and poured into a 1 L separatory funnel containing brine (600 mL) and extracted with Et2O (3*200 mL). The combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated under reduced pressure. Purification by column chromatography through silica gel, eluting with 50:50 hexanes:EtOAc to 20:80 hexanes:EtOAc as a gradient, afforded the title compound as a yellow solid.

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

Reference:
Patent; Isabel, Elise; Lachance, Nicolas; Leclerc, Jean-Philippe; Leger, Serge; Oballa, Renata M.; Powell, David; Ramtohul, Yeeman K.; Roy, Patrick; Tranmer, Geoffrey K.; Aspiotis, Renee; Li, Lianhai; Martins, Evelyn; US2011/301143; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 22047-25-2, The chemical industry reduces the impact on the environment during synthesis 22047-25-2, name is Acetylpyrazine, I believe this compound will play a more active role in future production and life.

Preparation 4 1-Pyrazin-2-yl-ethyl amine The synthetic procedure used in this preparation is outlined below in Scheme F. To a solution of 1-pyrazin-2-yl-ethanone (2.0 g, 15.85 mmol) and ammonium acetate (19.337 g, 158.5 mmol) in methanol (50 mL) was added sodium cyanoborohydride (0.7 g, 11.1 mmol) in one portion. The reaction mixture was stirred overnight at room temperature. After removal of methanol, water (20 mL) was added to the residue and the resulting solution was basified by addition of sodium hydroxide to pH=13. The aqueous solution was extracted with dicholromethane and the combined organic phase was dried over sodium sulfate. Removal of the solvent under reduced pressure afforded 14.62 g of 1-pyrazin-2-yl-ethylamine, yield: 75%. MS (M+H)=124.

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, Acetylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Roche Palo Alto LLC; US2009/170874; (2009); 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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, A new synthetic method of this compound is introduced below., name: Methyl 2-aminopyrazine-3-carboxylate

Example 3a: methyl 3-amino-6-iodopyrazine-2-carboxylate 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 65 ¡ãC for 1 hour, added together with 0.5 equivalents of N-iodosuccinimide and maintained at 65¡ãC 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 10percent sodium bisulfite solution, dried on magnesium sulfate and concentrated to yield 8 g (88percent) of methyl 3-amino-6-iodopyrazine-2-carboxylate in the form of a yellow solid. LCMS (EI, m/z): (M+l) 280 1H NMR: deltaEta ppm (400 MHz, DMSO): 8.50 (1H, s, CHarom), 7.50 (2H, bs, NH2), 3.20 (3H, s, CH3).

The synthetic route of 16298-03-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; PIERRE FABRE MEDICAMENT; SOKOLOFF, Pierre; CACHOUX, Frederic; WO2014/16433; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

98-97-5, name is Pyrazine-2-carboxylic acid, 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: C5H4N2O2

General procedure: The N-hydroxysuccinimideesters of pyrazinecarboxylic acid and (5)-(+)-ibuprofen were prepared by dissolving the starting acid (0.200 g, 1.0 equiv) in dry tetrahydrofuran. With stirring at 0 C, NHydroxysuccinimide (1.0 equiv) was added followed by N,N-dicyclohexylcarbodiimideequiv). The mixture was warmed to ambient temperature and stirred for 24 h. The N,Ndicyclohexylurea was removed by filtration and the filtrate was concentrated to afford a solid that was purified by column chromatography.[001481 2, 5-Dioxopyrrolidin-1-yl pyrazine-2-carboxylate 14. The cmde white solid was purified by column chromatography (Si02, acetone/dichloromethane, 1:4) to give a white solid (0.2757 g, 77%). Mp: 161 – 164 C. ?H NMR (300 MHz, CDC13): oe 9.40 (d, J= 1.41H), 8.90 (d, J= 2.3 Hz, 1H), 8.83 (dd, J= 2.4, 1.5 Hz, 1H), 2.95 (s, 4H). ?3C NMRMHz, CDC13): oe 168.9, 159.6, 149.3, 147.1, 145.2, 140.2, 25.8. JR (neat): 3501, 3324, 3276, 3078, 2929, 2851, 1875, 1806, 1785, 1703, 1653, 1626, 1571, 1533, 1468, 1449, 1420, 1399, 1360, 1306, 1260, 1243, 1203, 1183, 1153, 1075, 1060, 1048, 1025, 1011, 995,892, 876, 853, 811, 782, 764, 713 cmi. HRMS calcd. for C9H8N304 [M+Hj 222.0509, found 222.0502.

The synthetic route of 98-97-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; THE REGENTS OF THE UNIVERSITY OF CALIFORNIA; BOARD OF TRUSTEES OF MICHIGAN STATE UNIVERSITY; PIRRUNG, Michael, C.; BAKAS, Nicole, A.; BACHMANN, Andre; (89 pag.)WO2017/156471; (2017); 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. 88625-24-5, name is 5-Chloropyrazine-2-carbaldehyde, A new synthetic method of this compound is introduced below., category: Pyrazines

4,4-Difluoropiperidine hydrochloride [CAS RN: 144230-52-4] (495 mg, 3.14 mmol,1.6 eq), 5-chloropyrazine-2-carbaldehyde [CAS RN: 88625-24-5] (280 mg,3.14 mmol, 1.0 eq) and sodium triacetoxyborohydride (1.32 g, 6.29 mmol,3.2 eq) were suspended in 17 mL 1,2-dichloroethane. Then, triethylamine (0.55mL, 3.93 mmol, 2.0 eq) was added and the reaction mixture was stirred at rtovernight. Then, water was added and the resulting phases were separated bythe use of a Whatman filter. The volatile components of the organic phase wereremoved in vacuo and the crude material was purified via preparative MPLC (Biotage Isolera; 25 g SNAP cartridge: hexane/ethyl acetate 9/1 -> hexane/ethyl acetate 1/1) to give 320mg (63% yield of theory) of the title compound.UPLC-MS (Method 1): R = 0.56 mm; MS (EI0): m/z = 248 [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; BAYER PHARMA AKTIENGESELLSCHAFT; BAeRFACKER, Lars; SIEMEISTER, Gerhard; HEINRICH, Tobias; PRECHTL, Stefan; STOeCKIGT, Detlef; ROTTMANN, Antje; WO2015/113927; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 122-05-4,Some common heterocyclic compound, 122-05-4, name is Pyrazine-2,5-dicarboxylic acid, molecular formula is C6H4N2O4, 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.

After dissolving 76.8 mmol of I2 in 70 ml of pyridine, was added to a 250 ml three-necked flask and heated to 100 C under a nitrogen atmosphere, A solution of 120 ml of pyridine (completed in 4 hours) containing 27.41 mmol of 2,5-dicarboxylic acid pyrazine was slowly added dropwise, After completion of the dropwise addition, heating was continued for 2 hours, cooled, filtered and washed with 50 ml of ether to give a brown powder solid. The powder solids were then placed in a round bottom flask and 150 ml of methanol was added, heated to reflux for 1 h, cooled, filtered, Followed by washing with 40 ml of methanol and 40 ml of diethyl ether to give a brown powder as an intermediate 2,5-dicarboxylic acid pyrazine pyridinium iodide.

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

Reference:
Patent; Zhengzhou University of Light Industry; LI, XILI; ZHOU, LIMING; LI, CAIFENG; GAO, LIJUN; FANG, SHAOMING; (15 pag.)CN103896972; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 939412-86-9, 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. 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a mixture of (l^S^-S-^ethoxycarbony^^^^-trimethylcyclopentanecarboxylic acid (4.93 g, 23.01 mmol) and TEA (9.62 mL, 69.0 mmol) and HATU (13.12 g, 34.5 mmol) in DCM (100 mL) was stirred at 12 C for 30 min. (3-chloropyrazin-2-yl) methanamine hydrochloride (4.97 g, 27.6 mmol) was added and the mixture was stirred at 12 C for overnight. The reaction was complete detected by LC-MS. The mixture was added DCM (100 mL) and washed and brine. The organic layer was dried over Na2S04, purified with silica gel to give the title compound. XH NMR (400MHz, CDC13): delta 8.46 (d, J=2.3 Hz, 1H), 8.34 (s, 1H), 6.70 (br. s., 1H), 4.81 – 4.66 (m, 2H), 3.69 (s, 3H), 2.74 (t, J=9.2 Hz, 1H), 2.65 (dt, J=6.8, 12.6 Hz, 1H), 2.34 – 2.22 (m, 1H), 1.91 – 1.80 (m, 1H), 1.54 (ddd, 3=4.1, 9.6, 13.7 Hz, 1H), 1.32 (s, 3H), 1.25 (s, 3H), 0.81 (s, 3H).

The synthetic route of (3-Chloropyrazin-2-yl)methanamine hydrochloride has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; LIU, Jian; KOZLOWSKI, Joseph, A.; BOGA, Sobhana Babu; GAO, Xiaolei; GUIADEEN, Deodialsingh; WANG, Jyhshing; LIU, Shilan; (85 pag.)WO2016/109219; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 123-32-0, name is 2,5-Dimethylpyrazine, 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 123-32-0, Quality Control of 2,5-Dimethylpyrazine

Preparation of 3,6-dimethyl-2- (4-chloro) benzoyl pyrazine, comprising the steps of:(1) 2,5-dimethyl pyrazine take 0.2mmol, 4- chloro-benzoyl formate 0.4mmol, 0.02 mmol silver phosphate, potassium persulfate 5mL reaction tube was placed 0.4mmol, 1.4mL was added dichloro methane, 0.6 mL of distilled water was added, and the mixture was placed in an oil bath at 40 heated, reaction 24h, cooled to room temperature to obtain a reaction solution;(2) The step (1) the resulting reaction mixture was directly concentrated to give a concentrate, the concentrate with ethyl acetate / petroleum ether = 1/2 (v / v) as the developing solvent, separation by thin layer chromatography to give 46 mg desired product in 94% yield.

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

Reference:
Patent; Henan Agricultural University; Wu Zhiyong; Zhao Mingqin; Li Yuan; (10 pag.)CN108101856; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem