Month: April 2021

Some common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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 4774-14-5

EXAMPLE 22 To a solution of diisopropylamine (0.78 g) in tetrahydrofuran (40 ml) is added dropwise a 1.6M solution of n-butyl lithium in hexane (4.82 ml) in a dry ice-acetone bath over a period of 3 minutes. The mixture is stirred in the same bath for 30 minutes. To the mixture is added dropwise a solution of 2,6-dichloropyrazine (0.50 g) in tetrahydrofuran (5 ml) at the same temperature over a period of 15 minutes, and the mixture is stirred for one hour. The reaction mixture is poured into dry ice, and the mixture is stirred at room temperature for one hour. The reaction mixture is diluted with a 10% aqueous hydrochloric acid solution in order to adjust the pH value thereof to about 2, and then extracted with ethyl acetate. The combined organic layers are extracted with a saturated aqueous sodium hydrogen carbonate solution, and the aqueous extract is washed with ethyl acetate, acidified with a 10% aqueous hydrochloric acid, and extracted with ethyl acetate. The combined organic layer is washed with water and a saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue is triturated with a mixture of chloroform and hexane (1:1) to give 2-carboxy-3,5-dichloropyrazine (234 mg) as a slightly brown crystalline powder, m.p. 139-141 C., MS (m/z): 191 (M-H)-.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 4774-14-5, its application will become more common.

Reference:
Patent; Yamada, Koichiro; Matsuki, Kenji; Omori, Kenji; Kikkawa, Kohei; US2003/32647; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 6164-79-0, name is Methyl 2-pyrazinecarboxylate, 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 6164-79-0, Recommanded Product: Methyl 2-pyrazinecarboxylate

To a 2L 3-neck round-bottomed flask under a nitrogen atmosphere was charged NaH (22.11 g, 552.77 mmol) (60% dispersion in oil). Toluene (250 mL) was charged to the flask and the resulting slurry was stirred for 15 minutes at 20 C. The slurry was allowed to settle and the toluene removed by decantation. Additional toluene (250 mL) was added and the slurry was stirred for at 20 C. Methyl propionate (53.23 mL, 552.77 mmol) suspended in anhydrous toluene (250 mL) was added dropwise over 30 minutes. The resulting slurry was then heated to reflux temperature (external oil bath a140 C.). To the refluxing suspension was charged methyl pyrazine-2-carboxylate (54.72 g, 394.83 mmol) in anhydrous toluene (300 mL) (from step 1 of the process) dropwise over a period of 45 minutes. The reaction contents were heated at reflux temperature for 2.5 hours. The resultant dark brown slurry was allowed to cool to 20 C. Saturated ammonium chloride solution (500 mL) was charged to the slurry in one portion and the biphasic solution was vigorously stirred for 120 minutes, then agitation was stopped and the phases were allowed to separate. The dark brown-coloured lower aqueous phase (approx. 500 mL) was removed and the remaining yellow/orange-coloured upper organic phase (approx. 900 mL) was retained and combined with toluene extracts (2*175 mL) of the aqueous phase. The organic phase was filtered to remove solid particulates and concentrated in vacuo a45 C. to a volume of 400 mL to yield the desired methyl-2-methyl-3-(pyrazin-2-yl)-3-oxopropionate, which was used directly in the next reaction step. A small analytical sample was concentrated in vacuo a35 C. to yield a viscous oil. Structure was confirmed by 1H NMR and 13C NMR.

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, Methyl 2-pyrazinecarboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Patrick Prendergast; US2004/53989; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 762240-92-6,Some common heterocyclic compound, 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, molecular formula is C6H8ClF3N4, 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.

Take 2.16g of Compound 2 was added to the reaction flask, dissolved with 30ml of ethyl acetate was added CDI1.94g, stirred at room temperature 30min, 3- (trifluoromethyl) -5,6,7,8-tetrahydro- [1, 2,4] triazolo [4,3-a] pyrazine hydrochloride 2.29g and 1.01 g of triethylamine, kept at room temperature and stirred overnight, respectively 1mol / ml hydrochloric acid, washed with 10ml, 1mol / l sodium hydroxide solution 10g washed, 10ml was washed with saturated brine, the organic phase was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to give a solid 3.34g, yield 85.3%.

The synthetic route of 762240-92-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Hefei Hua Fang Pharmaceutical Co., Ltd.; Gao, Yonghao; He, Yong; Peng, Fuyun; Feng, Baolong; Wu, Zhonghao; (6 pag.)CN105330664; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 912773-24-1, 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. 912773-24-1, name is 6-Bromoimidazo[1,2-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows.

To a solution of 6-bromoimidazo[1,2-a]pyrazine 16 (2.0 g, 10.1 mmol) and (4-((tert-butoxycarbonyl)amino)phenyl) boronic acid (3.5 g, 14.8 mmol) in DME aqueous solution (DME : H2O = 2 : 1, 100 mL), were added Pd(PPh3)4 (578 mg, 0.5 mmol) and K2CO3 (2.8 g, 20.2 mmol). The solution was degassed with argon for 5 min and then stirred at 80 for 12 h. The reaction suspension was cooled to room temperature and filtered through Celite. The solvent was removed by rotary evaporation, the residue was treated with water and extracted with ethyl ether, then washed with brine, dried over by magnesium sulfate. The organic layer was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (MeOH/DCM, v/v = 1:100) to afford tert-butyl (4-(imidazo[1,2-a]pyrazin-6-yl)phenyl)carbamate (2.4 g, 7.7 mmol) as yellow solid, yielded 76.2%. 1H NMR (400 MHz, DMSO-d6) delta 9.46 (s, 1H), 9.09 (s, 1H), 9.06 (s, 1H), 8.03 (s, 1H), 7.90 (d, J = 8.8 Hz, 2H), 7.81 (s, 1H), 7.56 (d, J = 8.8 Hz, 2H), 1.47 (s, 9H). LC-MS (ESI) m/z 311 [M + H] +.

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

Reference:
Article; Cui, Shengyang; Wang, Yongjin; Wang, Yuting; Tang, Xia; Ren, Xiaomei; Zhang, Lei; Xu, Yong; Zhang, Zhang; Zhang, Zhi-Min; Lu, Xiaoyun; Ding, Ke; European Journal of Medicinal Chemistry; vol. 179; (2019); p. 470 – 482;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 78342-42-4, The chemical industry reduces the impact on the environment during synthesis 78342-42-4, name is (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, I believe this compound will play a more active role in future production and life.

A solution of nBuLi (6.78 mL, 10.86 mmol, 1.6 M) in hexanes was added dropwise to a solution of (S)-2-isopropyl-3,6-dimethoxy-2,5-dihydropyrazine (2.0 g, 10.86 mmol) in 20 mL of THF at -78 ¡ãC. After stirring for 30 mm at -78 ¡ãC, a solution of 5-bromo-2-(bromomethyl)-1,3- difluorobenzene (3.10 g, 10.86 mmol) in 10 mL of THF was added and the reaction mixture was stirred at -78 ¡ãC for 3 h. Then 20 mL of saturated NH4C1 solution was added. After the reaction mixture was warmed to room temperature, 150 mL of water was added and the mixture was extracted with EtOAc three times. The combined organic layers were dried over MgSO4, filtered, and concentrated. Purification by silica gel chromatography (eluting with 0 to 15percent EtOAc/Hexanes) afforded (2R, 5 S)-2-(4-bromo-2, 6-difluorobenzyl)-5 -i sopropyl-3 ,6-dimethoxy- 2,5-dihydropyrazine. ?H NIVIR (CDC13, 300 MHz) (ppm): 7.03 (d, J = 7.04 Hz, 2H), 4.14-4.32 (m, 1H), 3.71 (s, 3H), 3.58 (s, 3H), 3.13-3.33 (m, 1H), 2.79-2.93 (m, 1H), 2.13-2.33 (m, 1H), 1.00 (d, J 7.04 Hz, 3H), 0.64 (d, J 7.04 Hz, 3H). MS: (ESI, m/z): 389, 391 [M+H]t

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, (S)-2,5-Dihydro-3,6-dimethoxy-2-isopropylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; FORMA THERAPEUTICS, INC.; ZABLOCKI, Mary-Margaret; GUERIN, David J.; NG, Pui Yee; WANG, Zhongguo; SHELEKHIN, Tatiana; CARAVELLA, Justin; LI, Hongbin; IOANNIDIS, Stephanos; (518 pag.)WO2019/32863; (2019); 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. 56423-63-3, name is 2-Bromopyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C4H3BrN2

The above oily liquid was dissolved in 10 mL of ethylene glycol dimethyl ether and 2 mL of water, and 2-bromopyrazine (88 mg, 0.55 mmol) and Pd(PPh3)4 (16 mg, 0.014 mmol) and Na2CO3 (145 mg, 1.37 mmol) were stirred at 100 C for 2 hours under nitrogen. After cooling to room temperature, the reaction solution was poured into 60 mL of water and extracted three times with 20 mL of ethyl acetate. The combined ethyl acetate was washed with brine and dried over anhydrous sodium sulfate. Filtered, and concentrated by column chromatography (petroleum ether / ethyl acetate 1/1) to give 30mg as a white solid powder that is Compound A-3a.

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; Shenzhen Tajirui Bio-pharmaceutical Co., Ltd.; Wang Yihan; Zhao Jiuyang; (35 pag.)CN109651359; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 22047-25-2, 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. 22047-25-2, name is Acetylpyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a stirred solution of acetylpyrazine (0.041 g, 0.30 mmol) and ground 3 A dried molecular sieves in methanol was added dropwise 4,4’methyledianiline (0.029 g, 0.15 mmol) in methanol and a few drops of glacial acetic acid. The mixture was heated under reflux for 24 h. The molecular sieves were removed by filtration and the filtrate treated with FeCl2 4H2O (0.019 g, 0.10 mmol) and refluxed for 2 hours. The purple solution was treated with methanolic ammoniumhexafluorophosphate solution, the resulting precipitate were filtered off and dried over P4O10. recrystalization from CH3CN/diisopropylether afforded 0.052g, yield 58% of purple crystals of [Fe2L3](PF6) 1HNMR (300MHz, CD3CN, 298K) d = 9.68 (1H, br, H6/5) 8.82 (1H, br, H3), 7.37 (2H, br, H6/5, HPh), 6.77 (1H, d, J = 7.0 Hz, HPh), 6.77 (1H, d, J = 7.0 Hz, HPh), 4.65 (1H, d, J = 6.4 Hz, HPh), 4.04 (1H, s, CH2), 2.47 (3H, s, CH3).

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

Reference:
Patent; UNIVERSITY OF WARWICK; WO2005/33119; (2005); 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 19745-07-4 as follows. Computed Properties of C4H2Cl2N2

To a mixture of 2,5-dichloropyrazine in 2-propanol (0.2 M) was added 4- hydroxypiperidine (2.2 equiv.). The reaction was heated in the microwave at 160 0C for 10 min.The solvent was evaporated under reduced pressure and the title compound was purified by flash chromatography eluting with ethyl acetate

According to the analysis of related databases, 19745-07-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MERCK FROSST CANADA LTD.; WO2008/46226; (2008); A1;,
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. 144692-85-3, name is 2,3-Dichlorofuro[3,4-b]pyrazine-5,7-dione, This compound has unique chemical properties. The synthetic route is as follows., Application In Synthesis of 2,3-Dichlorofuro[3,4-b]pyrazine-5,7-dione

Under air, a test tube was charged with 2,3-dichlorodiazaphthalic anhydride (400mg, 1.826mmol) and 2-bromoethylamine hydrobromide (384mg, 1.872mmol). Acetic anhydride (400muL) was added and the reaction sealed and heated to 120C for 30min. The reaction was cooled to ambient temperature and diluted with H2O (2mL). The crude solid was filtered and washed with H2O (2¡Á5mL) and purified by eluting through a plug (SiO2; CH2Cl2) to obtain the product as a mixed halo compound, which was used without further purification. Yield=417mg. Compound 5b was obtained as an approximately 1:1 mixture of the dichloro- and bromochloro- diazaphthalimide as a result of the ammonium counter anion becoming partially exchanged into the pyrazine ring. Attempts to prevent this halide exchange using excess NH4Cl yielded significant amounts of inseparable 5a as a side-product. Nevertheless, 5b was reacted on as the mixed halide species with no significant impact on the subsequent synthesis of 1b (vide supra). (0024) 1H NMR (500MHz, CDCl3): delta 4.24 (t, 3JHH=6.4, 2H, CH2), 4.23 (t, 3JHH=6.4, 2H, CH2), 3.67 (t, 3JHH=6.4, 2H, CH2), 3.66 (t, 3JHH=6.4, 2H, CH2). 13C{1H} NMR (126MHz, CDCl3): delta 162.0, 161.9, 161.8, 161.8, 156.4, 154.1, 150.3, 147.4, 143.9, 143.7, 143.7, 143.4, 40.2, 40.2, 27.7, 27.7. HR ESI-MS positive ion: 379.9013m/z [C8H4BrCl2N3O2+Na+MeOH]+ (calc. 379.8995), 423.8489m/z [C8H4Br2ClN3O2+Na+MeOH]+ (calc. 423.8492). Anal. Calcd for C8H4Br1.5Cl1.5N3O2 (347.17gmol-1): C, 27.68; H, 1.16; N, 12.10. Found: C, 28.34; H, 0.92; N, 11.26; error <0.9%. 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 144692-85-3. Reference:
Article; Knighton, Richard C.; Chaplin, Adrian B.; Tetrahedron; vol. 73; 31; (2017); p. 4591 – 4596;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 4858-85-9, 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. 4858-85-9, name is 2,3-Dichloropyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Dissolve 2,3-dichloropyrazine (20 g, 0.134 mol) in ethanol, and add hydrazine hydrate (21 g, 0.42 mol) in small portions for multiple times and reflux at 85 C.The reaction was detected by TLC until the reaction was complete. After the reaction solution was cooled, it was added to ice water and stirred.The precipitated solid was suction-filtered and the filter cake was dried to obtain 16.8 g of a yellow-yellow powder with a yield of 84.1%.

The synthetic route of 2,3-Dichloropyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Jiangxi Science and Technology Normal University; Zhu Wufu; Zheng Pengwu; Xu Shan; Liu Xiaobo; Zhang Qian; Zhou Lingjia; Han Haoyun; Yu Li; Zhou Hualan; Qiu Yufeng; (25 pag.)CN110467616; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem