Month: February 2021

Related Products of 4858-85-9, A common heterocyclic compound, 4858-85-9, name is 2,3-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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, 5.06 g of 2,3-dichloropyrazine, 5.23 g of 4-fluorophenyl boronic acid, 22.16 g of cesium carbonate, and 200 mL of dioxane were put in a three-neck flask equipped with a reflux pipe, and 0.467 g of tris(dibenzylideneacetone)dipalladium(0) (abbreviation: Pd2(dba)3) and 2.5 mL of tricyclohexylphosphine (abbreviation: Cy3P) were added thereto while the mixture was stirred under a nitrogen atmosphere, and they were reacted at 85 C. for 11 hours. After the reaction, the reaction solution was cooled down to room temperature and filtrated. A solvent of the obtained filtrate was distilled off, and the obtained residue was refined with a column chromatography using dichloromethane as a development solvent, so that 2-chloro-3-(4-fluorophenyl)pyrazine was obtained (light yellow powder, yield: 55%).

The synthetic route of 4858-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Semiconductor Energy Labratory Co., Ltd.; US2008/312437; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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. Application In Synthesis of Pyrazine-2-carboxylic acid

The title compound (1, Scheme 1) was prepared following the previously described procedure [23] via the reaction of pyrazine-2-carboxylic acid (A) (5 mmol) with thionyl chloride (7.5 mmol) in dry toluene to yield the corresponding acyl chloride (B), which was subsequently reacted with 3-iodo-4-methylaniline (5 mmol) in dry acetone with pyridine (5 mmol). The reaction was stirred at room temperature for1 hour, then poured into cold water. The crude product was collected, adsorbed on silica and purified by flash chromatography(silica, gradient elution ethyl-acetate in hexane0 e30%). The yield of chromatographically pure product was 84% oftheoretical yield related to acid (A). Elementary composition(CHON) of 1 was in the range of ¡À0.4% of calculated values and themelting point was consistent with literature (141e142 C) measured, 142e143 C from literature [23]. The FT-IR spectrum(Fig. 1) was recorded using KBr pellets on a DR/JASCO FT-IR 6300 spectrometer. The FT-Raman spectrum (Fig. 2) was obtained on a Bruker RFS 100/s, Germany. For excitation of the spectrum, the emission of Nd:YAG laser was used with an excitation wavelengthof 1064 nm, a maximal power 150 mW; measurement of solid sample.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 98-97-5, its application will become more common.

Reference:
Article; Ranjith; Al-Abdullah, Ebtehal S.; Al-Omary, Fatmah A.M.; El-Emam, Ali A.; Anto; Sheena, Mary Y.; Armakovi?, Stevan; Armakovi?, Sanja J.; Zitko, Jan; Dolezal, Martin; Van Alsenoy; Journal of Molecular Structure; vol. 1136; (2017); p. 14 – 24;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 23688-89-3, 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. 23688-89-3 name is 6-Chloropyrazine-2-carboxylic acid, 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.

Intermediate 136-Ch[oro-N,N-dimethy[pyrazine-2-carboxamide A mixture of 6-ch[oropyrazine-2-carboxy[ic acid [CAS-RN: 23688-89-3] (510 mg,3.22 mmo[, 1.0 eq), dimethy[amine [CAS-RN: 124-40-3] (1.61 mL, 2M so[ution inTHF, 3.22 mmo[, 1.0 eq), HATU (1.47 g, 3.86 mmo[, 1 .2 eq) and DIPEA (1 .78 mL, 9.65 mmo[, 3.0 eq) was disso[ved in 15 mL DMF and stirred at rt overnight. The reaction mixture was partitioned between ethy[ acetate and water. The organic phase was washed with brine and separated by the use of a Whatman fi[ter. Thevo[ati[e components were removed in vacuo and the crude materia[ obtained was purified via preparative MPLC (Biotage Iso[era; 25 g SNAP cartridge: hexane/ethy[ acetate 8/2 -> hexane/ethy[ acetate 4/6) to give 330 mg (50% yie[d of theory) of the tit[e compound.UPLC-MS (Method 1): R = 0.67 mm; MS (EI0): m/z = 186 [M]¡Â.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 6-Chloropyrazine-2-carboxylic acid, and friends who are interested can also refer to it.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; BAeRFACKER, Lars; PRECHTL, Stefan; SIEMEISTER, Gerhard; WENGNER, Antje Margret; ACKERSTAFF, Jens; NOWAK-REPPEL, Katrin; BADER, Benjamin; LIENAU, Philip; STOeCKIGT, Detlef; WO2014/118186; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 109-08-0, 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 109-08-0 as follows.

[00401] Intermediate 26: Synthesis of l-phenyl-2-(pyrazin-2-yl)ethanone[00402] To a mixture of diisopropyl-amine (1.29 g, 12.7 mmol) in anhydrous THF (10 mL) was added w-BuLi (2.5 M/L in hexane, 4.7 mL, 11.7 mmol) at -78C, after being stirred for 30 minutes, a solution of 2-methylpyrazine (1 g, 10.6 mmol) in THF (5 mL) was added, and the mixture was stirred at -78C for 30 minutes, a solution of methyl benzoate (1.4 g, 10.6 mmol) in THF (5 mL) was added, and the mixture was stirred at this temperature for 3 hours. When TLC indicated that the starting material was consumed, the reaction mixture was diluted with EtOAc, and the mixture was washed with water and brine, and concentrated. The residue was purified by column chromatography (PE:EtOAc=30: l) to give Intermediate 26 (700 mg, yield 33.3%).

According to the analysis of related databases, 109-08-0, the application of this compound in the production field has become more and more popular.

Reference:
Patent; N30 PHARMACEUTICALS, LLC; SUN, Xicheng; QIU, Jian; WO2011/38204; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, 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 5521-55-1, Safety of 5-Methylpyrazine-2-carboxylic acid

1) 5-Methylpyrazine-2-carboxylic acid N-methoxy-N-methylamide Triethylamine (28.9 mL) was added to a solution of 5-methylpyrazine-2-carboxylic acid (13.0 g), 3-(3-dimethylaminopropyl)-1-ethylcarbodiimide hydrochloride (19.8 g), 1-hydroxybenzotriazole (14.0 g), and N, O-dimethylhydroxyamine hydrochloride (10.1 g) in N, N-dimethylformamide (130 mL) at room temperature, and the resultant mixture was stirred for 63 hours. Water and ethyl acetate were added to the reaction solution, and the mixture was partitioned. The organic layer was dried over anhydrous sodium sulfate. After separation by filtration, a residue obtained by evaporating the solvent under reduced pressure was purified by silica gel column chromatography (hexane-ethyl acetate), to obtain 5-methylpyrazine-2-carboxylic acid N-methoxy-N-methylamide (12.3 g, 72%) as an oily product. 1H-NMR(400MHz, CDCl3)delta: 2.63(3H, s), 3.41(3H, s), 3.74(3H, s), 8.46(1H, s), 8.82(1H, s). FAB-MSm/z: 182(M+H)+.

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

Reference:
Patent; DAIICHI PHARMACEUTICAL CO., LTD.; EP1785418; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 33332-28-4, The chemical industry reduces the impact on the environment during synthesis 33332-28-4, name is 2-Amino-6-chloropyrazine, I believe this compound will play a more active role in future production and life.

Pre Step A 6-(Methyloxy)-2-pyrazinamine A mixture of 6-chloro-2-pyrazinamine (200 mg, 1.544 mmol) and sodium methoxide (250 mg, 4.63 mmol) in methanol (3.9 ml) was heated to 130 C. via a microwave reactor for 60 min. The crude product mixture was purified by RP-HPLC to give 6-(methyloxy)-2-pyrazinamine (154 mg, 1.231 mmol, 80% yield). MS (ES+) m/z 125.8 (MH+).

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-6-chloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Glaxosmithkline LLC; Aubart, Kelly M.; Benowitz, Andrew B.; Fang, Yuhong; Hoffman, James; Karpinski, Joseph M.; Knox, Andrew Nicholson; Liao, Xiangmin; Qin, Donghui; Shi, Dongchuan; Spletstoser, Jared T.; US2013/345120; (2013); A1;; ; Patent; GlaxoSmithKline Intellectual Property (No. 2) Limited; Aubart, Kelly M.; Benowitz, Andrew B.; Fang, Yuhong; Hoffman, James; Karpinski, Joseph M.; Knox, Andrew Nicholson; Liao, Xiangmin; Qin, Donghui; Shi, Dongchuan; Spletstoser, Jared T.; US8901119; (2014); B2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 109-08-0, A common heterocyclic compound, 109-08-0, name is 2-Methylpyrazine, molecular formula is C5H6N2, 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.

Step C – Synthesis of mt 7-3 To a solution of 2-methylpyrazine (272 mg, 2.9 mmol) and HIVIPA (520 mg, 2.9 mmol) in THF (2.5 mL) was added LDA (1.6 mL, 3 mmol) at -78¡ãC dropwise. The mixture was allowed to stir at -78¡ãC for 30 minutes before a solution of mt 7-2 (600 mg, 2.45 mmol) in 2 mL of THF was added. The mixture was allowed to warm to room temperature for 3 hours before itwas quenched with 10 mL of saturated NH4C1 solution. The resulting mixture was extractedwith EtOAc (3 x 10 mL) and the combined organic washings were dried over sodlum sulfate,filtered and in vacuo. The resulting residue was purified using column chromatography (25percentEtOAc/ petroleum ether) to provide mt 7-3 (100 mg, 12percent). MS (ES): m/z (M+H) 339.

The synthetic route of 109-08-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; COBURN, Craig A.; MALETIC, Milana; SOLL, Richard; LI, Chunsing; LUO, Yunfu; QI, Zhiqi; WO2014/178; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

117103-53-4, name is 2-Bromo-5-nitropyrazine, 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. Computed Properties of C4H2BrN3O2

Step D: fert-butyl ethyl (5-nitropyrazin-2-yl)propanedioate: A suspension of NaH (60 %, 3.0 g, 75 mmol) in 100 mL of DMF was added tert-butyl ethyl propanedioate (14.1 g, 75 mmol) dropwise at 25 C. The mixture was stirred at 40 C for 30 minutes and 2-bromo-5-nitropyrazine (10.2 g, 50 mmol) in 50 mL of DMF was added dropwise. The resulting suspension was stirred at 50 C for 2 hours and diluted with 500 mL of EtOAc. The mixture was washed with water (100 mLx3), brine, dried over anhydrous Na2S04 and concentrated. The residue was purified by column chromatography (petrol ether : EtOAc = 5 : 1) to afford tert-butyl ethyl (5-nitropyrazin- 2-yl)propanedioate.

The synthetic route of 117103-53-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DONG, Shuzhi; PASTERNAK, Alex; SUZUKI, Takao; GU, Xin; FU, Qinghong; JIANG, Jinlong; DING, Fa-Xiang; TANG, Haifeng; DEJESUS, Reynalda K.; WO2015/96035; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 873-42-7, name is 2-Amino-3,5-dichloropyrazine, 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 873-42-7, Product Details of 873-42-7

General procedure: To the mixture of o-aminohalopyrazine (0.8 mmol) 1 in solvent was added NaOH (2.8 mmol, 3.5 eq), and stirred at T’ for 20 min. Isothiocyanate (0.92 mmol, 1.15 eq) 2 was added to the solution dropwise and heated at T”. The progress of the reaction was monitored by TLC. When all the starting material had been consumed, the mixture was allowed to room temperature. The product was isolated by the method described in Table 1.

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; Kwak, Se Hun; Lee, Gee-Hyung; Gong, Young-Dae; Bulletin of the Korean Chemical Society; vol. 33; 12; (2012); p. 4271 – 4274;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 762240-92-6, A 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, 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.

Into a 50 mL round-bottom flask was added 20 mL acetonitrile, followed by the addition of phenyl-butyric acid derivative (3.87 g, 0.01 mol) and triazolopyrazine hydrochloride (228 g, 0.01 mol). The temperature of the reaction mixture was cooled down to 0 C. in an ice-salt bath. 1-Hydroxylbenzotriazole (1.62 g, 0.012 mol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (2.29 g, 0.012 mol) were further added. 3 g Triethylamine was then added dropwise and the mixture was stirred at room temperature for 24 h. The reaction solution was washed with 3 X 20 mL distilled water. The obtained organic layers were collected and dried over anhydrous magnesium sulfate for 1 h. Then, the desiccant was filtered off and the resulting reactant was concentrated to 5.1 g. The yield was 91%.

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

Reference:
Patent; ZHEJIANG HISOAR PHARMACEUTICAL CO., LTD.; Pan, Xianhua; Li, Weijin; Zhang, Qunhui; Ruan, Libo; Yu, Wansheng; Deng, Fei; Ma, Tianhua; Huang, Mingwang; He, Minhuan; US2013/281695; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem