Month: June 2021

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. HPLC of Formula: C4H2Cl2N2

2,3-Dichloropyrazine A-1 (15 g; 100.68 mmol) and hydrazine hydrate 65% (15.509 ml; 201.37 mmol) are dissolved in 45 ml ethanol and stirred for 1 h at 80 C. While cooling down, a precipitate is formed. It is slurred up with a small amount of water and filtered off. It is washed with water and then dried to afford the product. Yield: 93% (13.6 g; 94.07 mmol); HPLC-MS: (M+H)+=145/147; tRet=0.34 min; method FECB5.

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

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; ENGELHARDT, Harald; GIANNI, Davide; SMETHURST, Christian; US2014/142098; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 243472-70-0,Some common heterocyclic compound, 243472-70-0, name is 5-Bromo-2,3-diphenylpyrazine, molecular formula is C16H11BrN2, 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.

General procedure: Trimethylamine(33% ethanol solution, 358 g, 2.0 mol) was added5-chloro-2,3-diphenylpiperazine (266 g, 1.0 mol) in ethyl acetate (1.3 L)And stirred at room temperature for 48 hours.A large number of solids are present.filter,The solid was washed with ethyl acetate (2 x 50 mL)Dried in high vacuum to give 283.5 g of a white solid,The yield was 87%.:_In the same manner as in Example 1, except that 5-bromo-2,3-diphenylpiperazine was used in place of 5-chloro-2,3-diphenylpiperazine,Preparation of 2,3-diphenylpiperazine trimethylammonium bromide with 2,3-diphenylpiperazine trimethylammonium chloride.The yield was 75%.

The synthetic route of 243472-70-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Suzhou Guohang Pharmaceutical Technology Co., Ltd.; Mei, Desheng; (11 pag.)CN106467496; (2017); A;,
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. 6270-63-9, name is Pyrazin-2(1H)-one, This compound has unique chemical properties. The synthetic route is as follows., category: Pyrazines

Example 181; (1SR,2RS)-1-methyl-cyclopropane-1,2-dicarboxylic acid 2-[(5-chloro-pyridin-2-yl)-amide]1-{[2-fluoro-4-(2-oxo-pyrazin-1-yl)-phenyl]-amide}; In analogy to example 178, step 3, (1SR,2RS)-2-(5-chloro-pyridin-2-ylcarbamoyl)-1-methyl-cyclopropanecarboxylic acid methyl ester (example 178, step 2) was reacted with 1-(4-amino-3-fluoro-phenyl)-1H-pyrazin-2-one (prepared from 2-fluoro-4-iodoaniline by reaction with 1H-pyrazin-2-one, Cu(I)I, N,N’-dimethylethylenediamine and cesium carbonate in dioxane at 120 C.) to give (I SR,2RS)-1-methyl-cyclopropane-1,2-dicarboxylic acid 2-[(5-chloro-pyridin-2-yl)-amide]1-{[2-fluoro-4-(2-oxo-pyrazin-1-yl)-phenyl]-amide} as off-white solid. MS 440.3 ([M-H]-).

According to the analysis of related databases, 6270-63-9, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Boehringer, Markus; Zbinden, Katrin Groebke; Haap, Wolfgang; Hilpert, Hans; Himber, Jacques; Humm, Roland; Iding, Hans; Knopp, Dietmar; Panday, Narendra; Ricklin, Fabienne; Stahl, Christoph Martin; US2006/106016; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 957344-74-0, These common heterocyclic compound, 957344-74-0, name is 5,8-Dibromoimidazo[1,2-a]pyrazine, 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.

5,8-dibromoimidazo[1,2-a]pyrazine (2.75 g, 9.90 mmol) prepared in step 1, cyclopropylamine (3.4mL, 49.50 mmol),N, N- diisopropylethylamine to (3.5 mL, 19.80 mmol) was dissolved in 1,4-dioxane (33 mL), the mixture at 100C stirred for 16 hours.Neutralized by addition of a saturated aqueous solution of sodium bicarbonate to the reaction solution and ethyl acetateExtracted with Tate.The extracted organic layer was washed with water. The organic layer was dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The resulting residue was purified by column chromatography (ethyl acetate: n- hexane = 1: 1) to give the title compound (530 mg, 92%)

The synthetic route of 957344-74-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; HANMI PHARM. CO., LTD.; HAM, YOUNG JIN; SON, JUNG BEOM; PARK, CHANG HEE; KANG, SEOK JONG; CHOI, JAE YUL; KIM, SEO HEE; (36 pag.)KR2015/113801; (2015); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 16298-03-6, The chemical industry reduces the impact on the environment during synthesis 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, I believe this compound will play a more active role in future production and life.

Methyl 3-AMINO-2-PYRAZINE-CARBOXYLATE (10 g, 65.3 mmol) was dissolved in glacial acetic acid (50 mL) by warming to approximately 45oC. To the warm solution was added bromine (3-7 MOL) in acetic acid (5 mL) dropwise and the resulting mixture was stirred at room temperature for 20 minutes. The solution was diluted with water (300 ML) and then stirred at room temperature for 30 minutes, which resulted in a precipitate. The precipitate was then filtered, washed with water and dried to afford methyl 3-AMINO-6-BROMO-2-PYRAZINE-CARBOXYLATE as a yellow solid (14. 2 g, 94 %). IH NMR (300 MHz, CDC13) 63. 99 (s, 3 H), 8.30 (s, 1 H) ; 13C NMR (100 MHZ, CDC13) A 53.02, 123.49, 124.85, 150.24, 154.70, 166.04.

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-aminopyrazine-3-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; BIOGEN IDEC MA INC.; WO2004/92177; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route 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.

The mixture of 2-methylthiopyrazine (120 mg, 0.95 mmol) andMeI (203 mg 1.43 mmol) was stirred in a closed vial at 80 C for 2 h.The precipitated orange powder of [MMTP]I was washed withdiethyl ether (2 Chi 8 mL) and dried under vacuum. Yield: 230 mg(90%). 1H NMR (500.13 MHz, CD3CN): delta = 9.03 (dd, JHH = 5.1, 2.8 Hz,1H, C2-H), 8.73 (s, 1H, C5-H), 8.27 (s, 1H, C6-H), 4.25 (s, 3H,Me-N), 2.69 (s, 3H, Me-S). FT-IR (KBr, cm-1): 380 (vs), 420 (w), 449(s), 528 (m), 710 (s), 746 (s), 831 (s), 874 (s), 887 (s), 955 (s), 982 (s),1003 (m), 1124 (s), 1144 (w), 1173 (m), 1221 (vw), 1240 (s), 1260 (s),1281 (s), 1317 (vs), 1439 (m), 1454 (m), 1472 (m), 1528 (s), 1611 (s),2851 (vs), 2916 (vs), 2988 (s), 3028 (s), 3051 (s), 3100 (s). Anal. Calcdfor C6H9IN2S: , 26.88; , 3.38; N, 10.45. Found: , 26.9; , 3.3; N,10.3.

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

Reference:
Article; Artem’ev, Alexander V.; Bagryanskaya, Irina Yu; Journal of Molecular Structure; vol. 1173; (2018); p. 743 – 749;,
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. 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, A new synthetic method of this compound is introduced below., category: Pyrazines

(2) To a 100 mL eggplant flask were added the yellow oil (1.65 g) prepared in the above step, 2-chloro-3-hydrazinylpyrazine (1.26 g), and diisopropylethylamine (4.56 mL) under argon gas flow, and the resulting mixture was stirred at 80 C. for 4 hours. (1716) After the reaction was completed, the mixture was concentrated under reduced pressure, water was added thereto, and the resulting mixture was extracted with ethyl acetate. The resulting organic layer was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The resulting residues were subjected to silica gel chromatography (hexane:ethyl acetate=70:30 to 50:50) using YAMAZEN medium pressure preparative (Silica L (40 g)), the fractions comprising the target compound (Rf value=0.25 (hexane:ethyl acetate=1:1)) were collected, concentrated under reduced pressure, to the resulting residues was added diisopropyl ether, the precipitated solid was filtered, and dried under reduced pressure to give the title compound (1.53 g) (yield 62%) as a white solid. (1717) MS(CI) m/z: 284/286 [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; MITSUBISHI TANABE PHARMA CORPORATION; UBE INDUSTRIES, LTD.; NAKAJIMA, Tatsuo; HAYASHI, Norimitsu; ISHIZAWA, Kouhei; TSUZAKI, Yasunori; IWAMURA, Ryo; TSUBOIKE, Kazunari; US2019/185479; (2019); 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 59489-71-3 as follows. Product Details of 59489-71-3

EXAMPLE 1B 5-amino-2-pyrazinecarbonitrile A mixture of Example 1A (19.29 g, 105 mmol), freshly powdered KCN (16.9 g, 260 mmol), CuI (49.5 g, 260 mmol), 18-crown-6 (2.08 g, 7.8 mmol), and (PPh3)4Pd (1.8 g, 1.57 mmol) in N,N-dimethylformamide (600 mL) was stirred at room temperature for 30 minutes and heated to reflux in an oil bath preheated to about 200 C. The solution was stirred at reflux for 3 hours, cooled to room temperature, poured into ethyl acetate (1 L), filtered through diatomaceous earth (Celite), treated with silica gel (100 g), and concentrated. The concentrate was purified by flash column chromatography on silica gel with 60% ethyl acetate/hexanes to provide 11.9 g (94.4%) of the desired product. MS (APCI(+)) m/z 121 (M+H)+; 1H NMR (300 MHz, DMSO-d6) delta 8.40 (d, J=0.7 Hz, 1H), 7.90 (d, J=0.7 Hz, 1H), 7.47-7.69 (br s, 2H).

According to the analysis of related databases, 59489-71-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Li, Gaoquan; Li, Qun; Li, Tongmei; Lin, Nan-Horng; Mantei, Robert A.; Sham, Hing L.; Wang, Gary T.; US2004/259885; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 4949-13-7, 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 4949-13-7 as follows.

STEP 1. 2-FLUORO-3-IODOPYRAZINE Butyl lithium solution (2.5 M in hexane, 881 mL, 2.01 mol) and 1.5 L of dry THF were charged into a flame-dried 5.0 L round-bottomed flask. The flask was cooled to -50 C. and 2,2,6,6-tetramethylpiperidine (312.0 mL, 2.20 mol) was added dropwise. The reaction mixture was warmed to 0 C. without taking the cold bath away and kept at that temperature for 20 min. The reaction was then cooled to -78 C., and 2-fluoropyrazine (180 g, 1.84 mol) in 150 mL of THF was added dropwise. The mixture was kept at -78 C. for 5 min. Iodine (464 g, 1.84 mol) in 500 mL of THF was added dropwise and the reaction mixture was kept at -78 C. for 1 h. The reaction was quenched with the addition of 250 mL of concentrated HCl, 250 mL MeOH and 250 mL THF at -78 C. The cold bath was then removed, and aqueous sodium bisulfite was added to get rid of traces of unreacted iodine. The solvent was then evaporated and the residue was diluted with water and adjusted to pH 8. The mixture was extracted with ethyl acetate (3*1.5 L). Combined ethyl acetate layer was dried over sodium sulfate and concentrated. The crude product was purified by column chromatography (Silica:100-200 mess, solvent: 10% EtOAc/hexanes) to give the title compound as a white solid.

According to the analysis of related databases, 4949-13-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; AMGEN INC.; US2010/160280; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 486424-37-7, name is 3-Amino-6-bromopyrazine-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 486424-37-7, name: 3-Amino-6-bromopyrazine-2-carboxylic acid

Dichlorobis(triphenylphosphine)palladium (H) (0.04 g) was added to a solution of 1 – { 2-[2-methoxy-4-(4,4,5,5-tetramethyl- 1 ,3 ,2-dioxaborolan-2-yl)phenoxy]ethyl Jpyrrolidine (1.26 g), 3-amino-6-bromopyrazine-2-carboxylic acid (0.844 g) and 2M aqueous sodium carbonate solution (2.4 ml) in a 2:7:3:2 mixture of DMF:dimethoxyethane:water:ethanol (30 ml). The reaction mixture was heated to 1600C for 20 minutes in a IOOW microwave oven. The mixture was cooled to ambient temperature and diluted with methanol. The resultant mixture was added to an SCX ion exchange column which was eluted with methanol, followed by 2M methanolic ammonia solution. There was thus obtained 3-amino- 6-[3-methoxy-4-(2-pyrrolidin-l-ylethoxy)phenyl]pyrazine-2-carboxylic acid (1.2 g); Mass Spectrum: M+H* 359; RT 0.79 min.

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:
Patent; ASTRAZENECA AB; WO2009/7390; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem