Month: September 2021

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. 33332-28-4, name is 2-Amino-6-chloropyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2-Amino-6-chloropyrazine

EXAMPLE 3 N-(6-Chloro-pyrazin-2-yl)-2,6-dimethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide 2.0 g (7 mmols) of methyl 2,6-dimethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide and 1.1 g (8.4 mmols) of 2-amino-6-chloro-pyrazine were reacted in 150 ml of xylene analogous to Example 2, and the reaction product was isolated and recrystallized from ethylene chloride. 2.1 g (79percent of theory) of N-(6-chloro-pyrazin-2-yl)-2,6-dimethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide were obtained. Melting point: 296°-298° C. 1H-NMR (CDCl3 +d-TFA): delta=9.55 (s, 1,3′-H); 8.55 (s, 1,5′-H); 8.05-7.55 (m, 3,5-H, 7-H, 8-H); 3.00 (s,3,N-CH3); 2.60 (s,3,CH3).

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; Dr. Karl Thomae Gesellschaft mit beschrankter Haftung; US4533664; (1985); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 33332-25-1,Some common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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.

Example 35-Chloropyrazine-2-carboxylic acidFehler. Es ist nicht moglich, durch die Bearbeitung von Feldfunktionen Objekte zu erstellen. Methyl 5-chloropyrazine-2-carboxylate (CAS [33332-25-1], 1 g, 5.79 mmol) was dissolved in a mixture of THF (50 ml) and water (50 ml). Lithium hydroxide monohydrate (243 mg, 5.79 mmol) was added and the reaction mixture was stirred at RT overnight. The pH was adjusted to 1 with 1M HC1 and the product was extracted with three portions of EtOAc. The combined organic layers were dried over Na2S04 and concentrated under vacuum. The crude material was purified by flash chromatography (Si02, 50 g, 0 to 20% MeOH in DCM) to yield the title compound as white solid (741 mg, 81%). MS (ISP): m/z = 159.0 [M+H]+.

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; BORRONI, Edilio; GOBBI, Luca; HILPERT, Hans; HONER, Michael; MURI, Dieter; NARQUIZIAN, Robert; POLARA, Alessandra; WO2012/168175; (2012); 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. 41110-28-5, name is 3-Methylpyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows., COA of Formula: C6H6N2O2

In a 2-E flask, 3-methylpyrazine-2-carboxylic acid (Matrix, 19.95 g, 144 mmol) was suspended in MeOH (500 mE). The suspension was cooled in an ice-water bath, and concentrated sulfuric acid (Fluka, 27.3 mE, 506 mmol) was added over a time period of 5 mm. The reaction mixture was heated to 80 C. for 5 h. The reaction mixture was concentrated under reduced pressure and the residue was taken up in DCM (750 mE). The excess acid was neutralized careffilly with aqueous NaOH (SM, 200 mE). The aqueous layer was separated and extracted with DCM (250 mE). The combined organic layers were combined, dried over Mg504 and concentrated to afford the title compound (16.15 g, 106 mmol, 73%). MS mlz=153 (M+H).

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 41110-28-5.

Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); 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. 173253-42-4, name is 2-Amino-5-bromo-6-chloropyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2-Amino-5-bromo-6-chloropyrazine

Step 1: 4-(5-amino-3-chloropyrazin-2-yl)benzonitrile A mixture of 5-bromo-6-chloropyrazin-2-amine (1.04 g, 5.00 mmol), (4-cyanophenyl)boronic acid (0.882 g, 6.00 mmol), dichloro(bis{di-tert-butyl[4-(dimethylamino)phenyl]phosphoranyl})palladium (110 mg, 0.15 mmol), sodium carbonate (1.06 g, 10.0 mmol) in 1,4-dioxane (12.0 mL) and water (2.0 mL) was evacuated then filled with nitrogen. The resulting mixture was stirred at 90 C. for 4 h then cooled to room temperature. The mixture was diluted with methylene chloride (15 mL) and water (5 mL). The precipitates were collected by filtration and washed with methyl t-butyl ether then dried to afford the desired product (1.05 g, 91%). LC-MS calculated for C11H8ClN4 (M+H)+: m/z=231.0; found 231.1.

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; Incyte Corporation; Wu, Liangxing; Wang, Xiaozhao; Yao, Wenqing; Zhang, Colin; (38 pag.)US2016/9711; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 14667-55-1, A common heterocyclic compound, 14667-55-1, name is 2,3,5-Trimethylpyrazine, molecular formula is C7H10N2, 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.

A reaction mixture of AgNO3 (33.4 mg, 0.2 mmol), 2,3,5-trimethylpyrazine(tpyz) (24.2 mg, 0.2 mmol) and 2-nitroterephthalic acid (H2ntph) (42.2 mg, 0.2 mmol) and H2O (10 mL) was stirred for 30 min in air, then transferred and sealed in a 25 mL Teflon-linedstainless steel autoclave, which was heated to 100 C for 72 h. Aftercooling to room temperature, the resulting colorless prism crystals were washed with distilled water and dried in air. Yield based on silver is 68.72%. Elemental analysis: Anal. calc. (found) for AgC15H13N3O6:C, 39.95(41.00); H, 2.99 (2.96); N, 9.52 (9.57) %. IR (KBr, cm-1) data: 3275 (m), 3093 (w), 2922 (w), 2867 (w), 1707 (s), 1600 (vs), 1527 (vs),1396 (s), 1350 (s), 1292 (s), 1154 (m), 766 (m), 703 (m).

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:
Article; Yang, Yuan-Yuan; Zhou, Lin-Xia; Zheng, Yue-Qing; Zhu, Hong-Lin; Li, Wen-Ying; Journal of Solid State Chemistry; vol. 253; (2017); p. 211 – 218;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 4774-14-5, name is 2,6-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 4774-14-5, Formula: C4H2Cl2N2

2,6-dichloropyrazine dissolved in 200 mL dry toluene in an oven dried flask, were added under stirring: 0.42 g (0.46 mmol) Pd(0)2 dba3, 0.83 g (1.34 mmol) 2,2′-bis(diphenylphosphino)-1,1′-binaphtyl (BINAP), 7.36 g (40.2 mmol) 3,4,5-trimethoxyanilin and 4.41 g (46.9 mmol) Na-tert-butoxide. The reaction mixture was heated at 90 C. (bath temperature) for 4 hours under N2. After cooling, the toluene solution was filtered. The solid was retaken in 100 mL Me2CO, filtered through a 5 cm column of Kieselgel 60, and the resulting solution evaporated under vacuum. A portion of 2.53 g of title compound was obtained. The toluene filtrate was evaporated to dryness and then retaken in 70-80 mL boiling AcOEt. The solution was kept in a refrigerator over night and 2.57 g of solid title compoundcompound were collected by filtration. The filtrate was reduced to 18-20 mL and submitted to HPLC (Kieselgel 60, 0.015-0.043; eluent: AcOEt:cycloxane 2:1). A third fraction of 0.94 g of title compoundcompound was collected. The total yield was 6.04 g (61.1%). 1H-NMR (DMSO), delta (ppm), J (Hz): 3.63 (s, 3H, CH3O(4′)), 3.77 (s, 6H, CH3O(3’+5′)), 7.02 (s, 2H, Harom(2’+6′)), 7.96 (s, 1H, HP5), 8.14 (s, 1H, HP3), 9.79 (s, 1H, NH); MS, (C13H14ClN3O3), m/z: 296 [M++1, 100].

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, 2,6-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; THE WELLCOME TRUST LIMITED; US2008/15191; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 622392-04-5, A common heterocyclic compound, 622392-04-5, name is 2-Bromo-5-iodopyrazine, molecular formula is C4H2BrIN2, 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.

EXAMPLE 25 Step 1. 2-iodo-5-methoxy-pyrazine. Sodium methoxide (25% wt. in MeOH,0.321 mL, 1.4 mmol) was combined with N-methyi pyrrolidine (NMP) (1.28 mL) and warmed to 60 C. 2-bromo-5-iodo-pyrazine (0.40 g, 1.4 mmol) was added. The suspension was stirred at 60 0C for 1 hour. Combined with an additional 100 mg previously run reaction prior to work-up. Reaction mixture was partitioned between H2O and ethyl acetate and the aqueous layer was extracted (3x) with ethyl acetate. The combined extracts were dried over MgSO4, filtered and concentrated to give a brown oil which solidified to obtain 406 mgs of crude material. 1H NMR (400 MHz, CHLOROFORM-d) d ppm 3.90 (s, 3 H), 8.03 (d, J=1.4 Hz, 1 H), 8.29 (d, J=1.4 Hz, 1 H); MS (APCI+, m/z) 237.

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; PFIZER PRODUCTS INC.; WO2007/72151; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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. Formula: C5H2ClN3

(a). (3-Chloropyrazin-2-yl)methanamine hydrochloride was prepared as follows. To a solution of 3-chloropyrazine-2-carbonitrile (160 g, 1 .147 mol) in acetic acid (1.5 L) was added Raney Nickel (50% slurry in water, 70 g, 409 mmol). The resulting mixture was stirred under 4 bar hydrogen at room temperature overnight. Raney Nickel was removed by filtration over decalite and the filtrate was concentrated under reduced pressure and co-evaporated with toluene. The remaining brown solid was dissolved in ethyl acetate at 50C and cooled on an ice-bath. 2M hydrogen chloride solution in diethyl ether (1 .14 L) was added in 30 min. The mixture was allowed to stir at room temperature over weekend. The crystals were collected by filtration, washed with diethyl ether and dried under reduced pressure at 40C. The product brown solid obtained was dissolved in methanol at 60C. The mixture was filtered and partially concentrated, cooled to room temperature and diethyl ether (1000 ml) was added. The mixture was allowed to stir at room temperature overnight. The solids formed were collected by filtration, washed with diethyl ether and dried under reduced pressure at 40C to give 153.5 g of (3-chloropyrazin-2- yl)methanamine.hydrochloride as a brown solid (74.4 %, content 77 %).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 55557-52-3, its application will become more common.

Reference:
Patent; ACERTA PHARMA B.V.; HAMDY, Ahmed; ROTHBAUM, Wayne; IZUMI, Raquel; LANNUTTI, Brian; COVEY, Todd; ULRICH, Roger; JOHNSON, Dave; BARF, Tjeerd; KAPTEIN, Allard; (268 pag.)WO2016/24227; (2016); 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. 221136-66-9, name is Ethyl 2-(3-bromo-6-methyl-2-oxopyrazin-1(2H)-yl)acetate, This compound has unique chemical properties. The synthetic route is as follows., Recommanded Product: Ethyl 2-(3-bromo-6-methyl-2-oxopyrazin-1(2H)-yl)acetate

EXAMPLE 5 r3-(2.2-Difluoro-2-phenyl-ethylamino)-6-methyl-2-oxo-2H-pyrazin-1-vn- acetic acidThe title compound was prepared according to the procedure shown below and described in details thereinafter.n-Butanol (2919.6 g, 3.6 I), 3-bromo-6-methyl-2-oxo-2(2H-pyrazine acetic acid) ethyl ester (Reagent (A) 600 g, 2.14 mol 1 equiv.)), and 2,2- difluoro-2-phenylethylamine (Reagent (B) 675 g, 4.29 mol, 2.00 equiv.) were charged to the reaction vessel and the reaction mixture heated to reflux. The reaction mixture was maintained at reflux. The reaction was then cooled to 750C and a 25% solution of sodium hydroxide (759 g, 600 ml 2.68 equiv.) was added. The reaction mixture was stirred at 750C. A 22% hydrochloric acid solution (1010 g, 900 ml, 3.13 equiv.) was then added slowly to the reaction mixture. The reaction mixture was allowed to cool to room temperature and then stirred overnight. The next morning the reaction mixture was cooled to 1 O0C, filtered, the filtrate washed with n-butanol (2.1 I), and then dried at 550C to yield the title compound as a residue.

According to the analysis of related databases, 221136-66-9, the application of this compound in the production field has become more and more popular.

Reference:
Patent; JANSSEN PHARMACEUTICA, N.V.; WO2007/146553; (2007); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem