Category: 24241-18-7

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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below., 24241-18-7

Magnesium turnings (293.9mg, 12.1mmol, 3.0equiv) and I2 (153.6mg, 605mumol, 0.15equiv) were added to a dry 100-mL 2-necked round-bottom flask under an argon atmosphere. Freshly distilled THF (25mL) was added using a syringe. The mixture was stirred at 0¡ãC until the brown color of the I2 disappeared. Then, benzylbromide (1.44mL, 12.1mmol, 3.0equiv) was slowly added using a syringe. After 10min ZnCl2 was added and the mixture was stirred for 40min. To this mixture, bis(triphenylphosphine)palladium (II) dichloride (141.8mg, 0.20mmol, 0.05equiv) and a solution of 2-amino-3,5-dibromopyrazine (1.02g, 4.03mmol, 1.0equiv) in dry THF (25mL) were added sequentially at room temperature. The resulting orange-colored reaction mixture was stirred for 3 days at room temperature and then quenched with water (50mL) at 0¡ãC. The mixture was diluted with ethyl acetate (300mL) and water (100mL). The organic layer was separated and the aqueous layer was extracted with ethyl acetate (4¡Á200mL). The combined organic layers were dried over anhydrous Na2SO4 and concentrated on a rotary evaporator. The residue was dissolved in CH2Cl2 and purified by silica gel column chromatography (gradient elution: PE?EtOAc, 85:15?65:35) to afford compound 11 (738.2mg, 2.79mmol, 70percent) as viscous yellow oil. Rf=0.46 (silica gel, PE?EtOAc, 7:3); 1H NMR (400MHz, CDCl3): delta=7.93 (s, 1H), 7.26?7.21 (m, 2H), 7.20?7.15 (m, 1H), 7.15?7.10 (m, 2H), 4.40 (br s, 2H), 3.99 (s, 2H); 13C NMR (100MHz, CDCl3): delta=152.3, 142.6, 141.9, 135.8, 129.2, 128.6, 127.4, 126.4, 40.9; IR (neat): numax=3472, 3314, 3200, 3060, 3027, 2919, 2850, 1605, 1555, 1529, 1494, 1424, 1389, 1340, 1261, 1220, 1158, 1117, 1073, 1048, 1028, 1002, 923, 905, 791, 759, 726, 696, 634cm?1; HRMS (ESI): calcd for C11H1179BrN3+ 264.0131; found 264.0133; calcd for C11H1181BrN3+ 266.1414; found 266.0113. The spectroscopic data are in good agreement with those reported in the literature.11d

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; Vece, Vito; Vuocolo, Giuseppina; Tetrahedron; vol. 71; 46; (2015); p. 8781 – 8785;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below. 24241-18-7

To a solution of 3,5-dibromopyrazin-2-amine (40.0 g, 158 mmol), TEA (66.1 mL, 475 mmol), and copper(I) iodide (0.301 g, 1.58 mmol) in THF (1172 ml) was added PdCl2(PPh3)2 (1.11 g, 1.58 mmol). The reaction mixture was cooled at about 0 C. and a solution of (trimethylsilyl)acetylene (20.8 mL, 150 mmol) in THF (146 mL) was added drop-wise. The reaction mixture was stirred at about 0-10 C. for about 7 h and then concentrated under reduced pressure. The dark brown residue was dissolved in DCM (600 mL) and filtered through a Celite pad (3 cm in height¡Á9 cm in diameter) while eluting with DCM (300 mL). The filtrate was washed with water (2¡Á500 mL) and brine (500 mL), dried over anhydrous MgSO4, filtered through a Florisil pad (1 cm in height by 9 cm in diameter) while washing with DCM/MeOH (9:1, 200 mL), and concentrated under reduced pressure to give a brown solid. The solid was triturated and sonicated with warm petroleum ether (b.p. 30-60 C., 250 mL), cooled and collected, washing with petroleum ether (b.p. 30-60 C.; 2¡Á100 mL), and dried in a vacuum oven at about 70 C. to give 5-bromo-3-((trimethylsilyl)ethynyl)pyrazin-2-amine (34.6 g, 70%): LC/MS (Table 2, Method d) Rt=1.59 min; MS m/z: 272 (M+H)+.

The synthetic route of 24241-18-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ABBOTT LABORATORIES; US2009/312338; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 24241-18-7 name is 2-Amino-3,5-dibromopyrazine, 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. 24241-18-7

Preparation of compound 36a: 3,5-dibromopyrazin-2-olTo a stirred solution of 3,5-dibromopyrazin-2-amine (30 g, 0.12 mol) in AcOH (300 ml_) was added dropwise cone. H2SO4 (50 ml_) at 15-25 0C. To the resulting solution was then added dropwise a solution of NaNO2 (16.6 g, 0.24 mol) in water (100 ml_) at 10-15 0C during a period of 1.5 h. After the addition, the resulting mixture was stirred at 10-15 0C for 1 h. The reaction mixture was poured into water (3 L) and extracted with EtOAc (1 L x 3). The combined organic layers were washed with saturated NaHCOs (1 L x 3) and brine (1 L) in sequence, dried over Na2SO4 and concentrated in vacuo which gave the title compound 36a as a yellow solid (24 g, 79.4%). 1H NMR (400 MHz, CDCI3): 7.44 (s, 1 H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-3,5-dibromopyrazine, and friends who are interested can also refer to it.

Reference:
Patent; PFIZER INC.; NINKOVIC, Sacha; BRAGANZA, John Frederick; COLLINS, Michael Raymond; KATH, John Charles; LI, Hui; RICHTER, Daniel Tyler; WO2010/16005; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, A common compound: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

To the reaction flask was added tetrahydrofuran (50 ml). trimethylsilylacetylene (580 mg, 5.9 mmol), triethylamine (1.2 g, 11.8 mmol), CuI (0.1 g), Pd(PPh3)4 (0.1 g) and the compound 3,5-dibromo-2-aminopyrazine 1a (1.0 g, 3.95 mmol) were reacted under nitrogen for 3 hours at room temperature.TLC showed the reaction was completed, 50ml of water was added and extracted with ethyl acetate (30mL) twice the aqueous phase, the organic phases are combined,Once, dried over anhydrous sodium sulfate washed with brine, and dried to give the crude product under reduced pressure using a rotary evaporator,Through the column to give the crude title compound 5a (0.5g, 18.5mmol), a yield of 47.1%

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-3,5-dibromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Shanghai Huahuituo Pharmaceutical Technology Co., Ltd.; Zhejiang Huahai Pharmaceutical Co., Ltd.; Xu Xin; Zhang Tian; Li Yunfei; Wang Guan; Zhu Weibo; Li Qiang; Qu Minkai; Zhang Linli; Song Jinqian; Liu Lei; Chen Haiji; Liu Qiang; Wang Yijin; Ge Jian; (67 pag.)CN109535164; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below.

Step 1: Synthesis of 5-Bromo-3-trimethylsilanylethynyl-pyrazm-2-yIamine.[0282] To a solution of 3,5-Dibromo-pyrazin-2-ylamine (3.00 g, 11.86 mmol) in DMF(35 ml) was added triethylamine (16 ml), then tetraldstriphenylphine palladium (0) (685 mg,0.59 mmol) and copper(i) iodide (271 mg, 1.42 mmol) were added sequentially. Finallytrimethylsilylacetylene (2.0 ml, 14.3 mmol) was added dropwise. The reaction mixture wasstirred at 120 C for 30 minutes and then directly adsorbed onto silica gel. Purification byflash chromatography on silica gel with a gradient of ethyl acetate/hexane afforded the titlecompound (2.30g, 71% yield) as yellow oil. MS: m/z 270.0/272.0 [MH+].

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; SGX PHARMACEUTICALS, INC.; WO2006/15124; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, A common compound: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

A mixture of 3,5-dibromopyrazin-2-amine (214 mg, 0.83 mmol) and phenyl boronic acid (100 mg, 0.8 mmol) in toluene (8 mL) was degassed and backfilled with nitrogen 3 times. Pd(PPtLs)4 (46 mg) was added followed by 2M K3PO4 (0.8 mL) and EtOH (1 mL). The mixture was heated at reflux for 18 h. The solution was cooled to room temperature, partitioned between EtOAc (25 mL) and water (5 mL). The layers were separated and the organic layer dried over Na2SO4, filtered and concentrated to an oil which was purified via silica gel chromatography (15% EtOAc/heptane) to afford the product (187 mg, 95% yield)

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-3,5-dibromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; WO2009/155388; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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. 24241-18-7

2-chloroacetaldehyde (0.79 g, 4 mmol) was slowly added to a freshly prepared solution of 3,5-dibromopyrazin-2-amine (1) (0.51 g, 2 mmol) in 2-propanol (20 mL). The mixture was stirred at reflux under a nitrogen atmosphere for 24 h. After cooling, CH2Cl2 (25 mL) and Et3N (1 mL) were added to the reaction solution. Thereafter, the solvent was evaporated under reduced pressure, and then the residue was washed with 11 mL mixed solution (water: 2-propanol = 10:1) for 2 times, filtered and dried under vacuum to give 6,8-dibromoimidazo[1,2-a]pyrazine (2) as a brown solid, which was pure enough to be used in the next step without further purification.

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 24241-18-7.

Reference:
Article; Huang, Boshi; Liang, Xin; Li, Cuicui; Chen, Wenmin; Liu, Tao; Li, Xiao; Sun, Yueyue; Fu, Lu; Liu, Huiqing; De Clercq, Erik; Pannecouque, Christophe; Zhan, Peng; Liu, Xinyong; European Journal of Medicinal Chemistry; vol. 93; (2015); p. 330 – 337;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, 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 24241-18-7 as follows.

Step 1 A 500 ml three necked round bottom flask was charged with 3,5-dibromopyrazine-2- amine (25.0 g, 0.0988 mole) which was dissolved in acetonitrile (250 ml). The reaction mixture was cooled to 0 C and triethylamine (50.0 g, 0.4941 mole), copper (1) iodide (2.26 g, 0.0119 mole), and Pd (PPh3)4 (5.7 g, 0.0049 mole) were added under nitrogen atmosphere. The reaction mixture was stirred for 10 min at 0 C followed by slow addition of trimethylsilylacetylene (10.7g, 0.1089 mole) over 15 min at the same temperature. After completion of the addition, the reaction mixture was warmed up to RT and stirred for 90 min. The reaction mixture was diluted by ethyl acetate and filtered. The filtrate was collected and washed with water. Layers were separated and aqueous layer was re-extracted by ethyl acetate. Combined organic layer was dried over Na2S04, filtered and concentrated to afford crude product which was purified using column purification to afford 20.0 g of 5-bromo-3-((trimethylsilyl)ethynyl)pyrazine-2-amine.

According to the analysis of related databases, 2-Amino-3,5-dibromopyrazine, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PRINCIPIA BIOPHARMA INC.; GOLDSTEIN, David, Michael; BRAMELD, Kenneth, Albert; OWENS, Tim; WO2014/81732; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a stirred solution of amine 1 (1.0 mmol) in dry DMF (3 mL) was added sodium hydride (60% dispersion in mineral oil, 2.2 mmol) and alkyl iodide (4.0 mmol). The resulting mixture was stirred under nitrogen at room temperature for 25 minutes. The reaction mixture was then quenched with water (6 mL), extracted with diethyl ether (2¡Á12 mL) and the combined organics were washed with brine, dried over sodium sulfate and concentrated. Biorg. Med. Chem. 2001, 9, 1149-1154.; Prepared from 2-amino-3,5-dibromopyrazine and iodomethane (568 mg, 4.00 mmol) according to general procedure 1. Purification by column chromatography (12 g ISCO column eluding with hexanes and ethyl acetate; gradient 100% hexanes to 70% hexanes) provided the substituted aminopyrazine (171 mg, 61%) as a yellow oil; 1H NMR (300 MHz, CDCl3) delta 8.11 (s, 1H), 3.07 (s, 6H).

The synthetic route of 2-Amino-3,5-dibromopyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Alcon, Inc.; US2006/142307; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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 24241-18-7, 24241-18-7

A mixture of 2-amino-3,5-dibromopyrazine (Aldrich, 6.0 g, 24.0 mmol) and 50% aqueous solution of chloroacetaldehyde (Aldrich, 4.8 mL) in 2-propanol (30 mL) was stirred and refluxed under N2 for 24 hr. CH2Cl2 (300 mL) and triethylamine (12 mL) were added and the solvent was evaporated. The residue was suspended in 10:1 H2O:2-propanol (200 mL), filtered, and the solid was washed on filter with 10:1 H2O:2-propanol (2¡Á100 mL). It was dried in a vacuum to yield pale beige solid (4.81 g, 74%).

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-3,5-dibromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; SCHERING CORPORATION; US2004/63715; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem