Category: 624-28-2

624-28-2, 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. 624-28-2, name is 2,5-Dibromopyridine. A new synthetic method of this compound is introduced below.

A mixture of 2,5-dibromopyridine (28.6 g, 121 mmol) and (S)-3-hydroxypyrrolidine (10.0 g, 115 mmol) in dry toluene (150 mL) was stirred under reflux for 20 h. The mixture was allowed to cool to rt, and the solvents were removed under reduced pressure. The residue was dissolved with EtOAc, and the resulting mixture was washed with aq. 10% K2CO3. The org. layer was dried over MgSO4, filtered, and the solvents were concentrated under reduced pressure. Purification of the residue by FC(CH2Cl2/MeOH 99:1?98:2?97:3?96:4?95:5?94:6?93:7) yielded the title compound (15.39 g, 55%). LC-MS: tR=0.45 min; ES+: 245.11.

At the same time, in my other blogs, there are other synthetic methods of this type of compound,624-28-2, 2,5-Dibromopyridine, and friends who are interested can also refer to it.

Reference:
Patent; Actelion Pharmaceuticals, Ltd.; US2009/88457; (2009); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2, The major producers of chemicals have been the Europe, Japan and China. Due to the growing call for a cleaner, greener environment, people will have to find innovative ways to maintain their relevance. Here is a compound 624-28-2, name is 2,5-Dibromopyridine. This compound has unique chemical properties. The synthetic route is as follows.

Intermediate 16: N-methyl-5-(tributylstannyl)pyridin-2-amine 2,5-Dibromopyridine (6 g, 25 mmol) in 40 ml 33% CH3NH2 in ethanol (13 eq.) was heated at 80 C. for 60 hours. After evaporation the solid residue was suspended in CH2Cl2, extracted 3* with 1 N HCl. The combined aqueous phase was neutralized with 2 N NaOH (pH-10-11), and then back extracted 3* with CH2Cl2. The combined CH2Cl2 phase was washed with water and dried over sodium sulfate. Concentration gave 4.457 g of 5-bromo-N-methylpyridin-2-amine as off-white solid. (yield: 95.3%).

While traditionally a conservative industry, chemical producers will need to modernize their PR strategies to stay relevant.we look forward to future research findings about 624-28-2, 2,5-Dibromopyridine.

Reference:
Patent; MacDonald, James E.; Jeffrey, McKelvy F.; Wong-Staal, Flossie; US2011/117055; (2011); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2 , The common heterocyclic compound, 624-28-2, name is 2,5-Dibromopyridine, molecular formula is C5H3Br2N, 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 1: 5-Bro -2-methoxypyridine A mixture of 2,5-dibromopyridine (5.5 g, 23.2 mmol) and NaOMe (3.76 g, 69.6 mmol) in MeOH (60 mL) was heated at 70C for 1 hour and then allowed to cool to room temperature. The reaction mixture was diluted with water (50 mL) and extracted with EtOAc (2 x 100 mL). The combined organic layers were dried over Na2S04 and concentrated under reduced pressure to give a pale yellow volatile oil (2.5 g, 58% yield). 1H NMR (400 MHz, DMSO-d6): delta 8.26 (s, 1H), 7.87 (dd, 1H), 6.81 (d, 1H), 3.82 (s, 3H).

The synthetic route of 624-28-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ENDO PHARMACEUTICALS INC.; SMITH, Roger, Astbury; KETHIRI, Raghava, Reddy; KRISTAM, Rajendra; LAPING, Nicholas, James; VENKATESHAPPA, Chandregowda; KULKARNI, Bheemashankar; DEVRAJ, Rajesh; DEWANG, Purushottam; WO2013/49559; (2013); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2, 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. 624-28-2, name is 2,5-Dibromopyridine. A new synthetic method of this compound is introduced below.

Step 1 5-Bromo-2-methoxypyridine To a solution of 2,5-dibromopyridine (1.4 g, 5.9 mmol) in DMF (10 mL) was added MeOH (4 mL), and 8N aqueous KOH (1 mL). The solution was heated to 100 C. for 2 h, then cooled and partitioned between Et2 O and H2 O. The organic layer was washed with brine, dried over MgSO4 and concentrated to provide 840 mg of the title compound, which was used in the next step without further purification.

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. 624-28-2, 2,5-Dibromopyridine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Merck Frosst Canada; US5922742; (1999); A;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2, A common compound: 624-28-2, name is 2,5-Dibromopyridine,molecular formula is C5H3Br2N, 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) 5-Bromo-pyridine-2-yl-hydrazine [0213] A mixture of 2,5-dibromopyridine (44.2 g, 0.187 moles), hydrazine hydrate (55% by weight, 105.7 mL, 1.87 mol), poly(ethylene glycol) (187.0 mL), 2-butanol (37.3 mL) and water (187.0 mL) under nitrogen is refluxed gently for 29 hours. The mixture is cooled and stirred for 20 hours. To the resulting slurry, cold water (220.0 mL) is added. The slurry is stirred for an additional 30 minutes and filtered. The cake is washed with cold water (3¡Á) and dried in a vacuum-oven (40-45 C.) for 48 hours. The title compound (30.5 g, 87%) may be obtained as off-white flakes.

With the rapid development of chemical substances, we look forward to future research findings about 624-28-2.

Reference:
Patent; Pfizer Inc; US2004/87615; (2004); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2, 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. 624-28-2, name is 2,5-Dibromopyridine, the common compound, a new synthetic route is introduced below.

A solution of 2,5-dibromopyridine (1.5 g, 6.3 mmol), L-Proline (0.08 g, 1.3 mmol), pyrrolidine (0.9 g, 0.0125 mol), AcOK (3.2 g, 33 mmol) and Cu I (0.3 g, 1.3 mmol) in DMF (40 mL) was stirred under N2 and at 850C for 12 h. The solution was filtered to remove the catalyst. The residue was diluted with H2O and was extracted with EA. The organic layer was washed with brine, dried over Na2SO4 and filtered. The filtrate was evaporated to give the target product (0.9 g, 63%). MS (m/z) (Mf+H): 243, 245.

Statistics shows that 624-28-2 is playing an increasingly important role. we look forward to future research findings about 2,5-Dibromopyridine.

Reference:
Patent; PROGENICS PHARMACEUTICALS, INC.; WO2009/155527; (2009); A2;,
Pyridine – Wikipedia,
Pyridine | C5H5N – 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. 624-28-2, name is 2,5-Dibromopyridine, the common compound, a new synthetic route is introduced below. 624-28-2

To a solution of 2,5-dibromopyridine (10.50 g, 44 mmol) in 210 mL of pyridine was added hydrazine hydrate (80%, 8.85 g, 176.4 mmol), and the mixture was heated to 110 C. and stirred further for 2 hours, then cooled to rt, and concentrated in vacuo. The residue was diluted with DCM (1500 mL). The resulted mixture was washed with aqueous NaOH solution (1 M, 350 mL), dried over anhydrous Na2SO4, and concentrated in vacuo to give the title compound as a gray solid (7.87 g, 94.8%). MS (ESI, pos. ion) m/z: 188.0[M+H]+; 1H NMR (600 MHz, DMSO-d6): delta 8.03 (d, J=2.3 Hz, 1H), 7.67 (s, 1H), 7.59 (dd, J=8.9, 2.5 Hz, 1H), 6.69 (d, J=8.9 Hz, 1H), 4.16 (s, 2H).

Statistics shows that 624-28-2 is playing an increasingly important role. we look forward to future research findings about 2,5-Dibromopyridine.

Reference:
Patent; Calitor Sciences, LLC; Xi, Ning; US2014/134133; (2014); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The major producers of chemicals have been the Europe, Japan and China. Due to the growing call for a cleaner, greener environment, people will have to find innovative ways to maintain their relevance. Here is a compound 624-28-2, name is 2,5-Dibromopyridine. This compound has unique chemical properties. The synthetic route is as follows. 624-28-2

A mixture of 2,5-dibromopyridine (12.2 g, 51.5 mmol) and (S)-hydroxypyrrolidine (2.80 g, 32.1 mmol) in toluene (50 mL) was heated to reflux overnight. The mixture was allowed to cool to rt, and the solvents were removed under reduced pressure. The residue was dissolved with EtOAc (150 mL), and the mixture was washed with aq. 10% K2CO3. The org. layer was dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (heptane?heptane/EtOAc 1:2) yielded the title compound (3.62 g, 46%). LC-MS: tR=0.48 min; ES+: 243.15.

Statistics shows that 624-28-2 is playing an increasingly important role. we look forward to future research findings about 2,5-Dibromopyridine.

Reference:
Patent; Actelion Pharmaceuticals Ltd.; US2009/62342; (2009); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2, 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. 624-28-2, name is 2,5-Dibromopyridine, molecular formula is C5H3Br2N, The 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.

Preparation 1 5-BROMO-PYRIDIN-2-YL-HYDRAZINE A 12 L three-necked round-bottomed flask equipped with a mechanical stirrer and a condenser, connected on top with a nitrogen bubbler and a thermometer, was charged with 2,5-dibromopyridine (442 g, 1.87 moles), hydrazine hydrate (55% wt., 1057 ml, 18.7 moles), poly(ethylene glycol) (average Mn about 300, 1.87 L), 2-butanol (373 ml) and water (1.87 L). The mixture was heated at reflux for 29 hours. The heating source was removed and the mixture was stirred for an additional 20 hours. To the resulting slurry, cold water (2.2 L) was added. The slurry was stirred for an additional 30 minutes and filtered. The cake was washed with cold water (3¡Á200 ml) and dried in a vacuum-oven (40 C.) for 48 hours. The title compound was obtained as off-white flakes (305 g, yield 87%). [0186] GCMS(m/z): 187 (M+). H1 NMR (400 MHz, CDCl3): delta 8.14 (d, J=2.0 Hz, 1H), 7.55 (dd, J=8.7/2.0 Hz, 1H), 6.66 (d, J=8.7 Hz, 1H), 5.89 (brs, 1H), 3.65 (brs, 2H).

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. 624-28-2, 2,5-Dibromopyridine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Pfizer Inc; US2004/87615; (2004); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

624-28-2, 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. 624-28-2, name is 2,5-Dibromopyridine. A new synthetic method of this compound is introduced below.

2,5-Dibromopyridine (10 g, 35.2 mmol) is dissolved in dry toluene (200 mL) under a nitrogen atmosphere and cooled to -78 C. n-Butyllithium (2.5M in hexanes, 2.5 mL, 38.7 mmol) is added at -78 C. over 20 minutes. The reaction mixture is stirred at -78 C. for 20 minutes. Oxetane-3-one (2.79 g, 38.7 mmol) in toluene (100 mL) is added then stirred at -78 C. for 30 minutes. Saturated aqueous ammonium chloride solution (50 mL) is added. The mixture extracted with ethyl acetate (2¡Á200 mL), separated, washed with brine solution (50 mL) and the solvent evaporated under reduced pressure. The crude material is purified using flash chromatography (35% ethyl acetate in hexane) to give the title compound (4.2 g): 1H NMR (400 MHz, DMSO-d6): delta 4.64 (2H, d), 4.87 (2H, d), 6.68 (1H, s), 7.55 (1H, d), 8.06 (1H, dd), 8.76 (1H, d).

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. 624-28-2, 2,5-Dibromopyridine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ZOETIS LLC; Billen, Denis; Curtis, Michael; Ewin, Richard Andrew; Goodwin, Richard M.; Johnson, Paul D.; Johnson, Timothy Allan; Kyne, Graham M.; Maddux, Todd M.; Sheehan, Susan Mary Kult; Vairagoundar, Rajendran; US2014/88046; (2014); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem