CAS 13534-97-9 5-Amino-2-bromopyridine products price,suppliers

To a solution of 2-bromo-5-nitropyridine (2.03 g, 10 mmol) in ethanol (48 mL), iron powder (2.8 g, 50 mmol), concentrated hydrochloric acid (1.9 mL) and water (9.1 mL) were sequentially added. 1. 1. Preparation of 6-bromopyridine-3-amine To a solution of 2-bromo-5-nitropyridine (64g, 0.317mol)/ethanol (1L) was successively added Fe powder (88g, 1.571mmol), concentrated hydrochloric acid (61mL) and water (287mL). The reaction mixture was reacted under reflux for 5h. The reaction mixture was cooled and filtered. The filtrate was concentrated and adjusted with a sodium bicarbonate solution to pH≈7-8, and re-filtered. The resulting filtrate was extracted with dichlormethane. The organic phase was dried with anhydrous sodium sulfate, and concentrated in a reduced pressure to produce 40.5g of the title compound as a pale-yellow solid in a yield of 74.4percent.2-Bromo-5-nitro-pyridine (202 g, 1.0 mol) was dissolved in methanol (2.0 L), and a saturated aqueous ammonium chloride solution (2.0 L) was added thereto, followed by stirring at 50° C. Then, iron (224 g, 4.0 mol) was slowly added thereto, followed by stirring at 50° C. for 6 hours. The reaction solution was cooled to room temperature and then filtered, followed by washing with ethyl acetate. The filtrate was diluted with water, followed by extraction with ethyl acetate (1.0 L×6). The extraction liquids were combined, washed with a saturated aqueous sodium hydrogen carbonate solution (2.0 L) and saturated aqueous sodium chloride, and dried over anhydrous sodium sulfate. Then, the solvent was removed under reduced pressure, and the obtained residue was purified by silica gel column chromatography (petroleum ether/ethyl acetate=1:1) to obtain the title compound (126 g, 73percent). [1152] 1H NMR (400 MHz, DMSO-d(Step 1) 6-Bromopyridin-3-amine (0221) (0222) 2-Bromo-5-nitro-pyridine (202 g, 1.0 mol) was dissolved in methanol (2.0 L), a saturated aqueous solution of ammonium chloride (2.0 L) was added thereto, the resulting mixture was stirred at 50° C., then iron (224 g, 4.0 mol) was slowly added thereto, and the resulting mixture was stirred at 50° C. for 6 hours. The reaction solution was cooled to room temperature and then filtered and washed with ethyl acetate. The filtrate was diluted with water and then extracted with ethyl acetate (1.0 L×6). The extracts were combined, washed with a saturated aqueous solution of sodium hydrogen carbonate (2.0 L) and a saturated saline solution, dried over anhydrous sodium sulfate, and then the solvent was removed under reduced pressure. The obtained residue was purified by silica gel column chromatography (petroleum ether:ethyl acetate=1:1) to obtain the title compound (126 g, 73percent). (0223) 1H NMR (400 MHz, DMSO-d0.282 g of 5percent Pd / C and lOmmol of anhydrous sodium sulfate were added to a 100 mL round bottom flask containing 20 mmol of 5-nitro-2-bromopyridine in 40 ml of tetrahydrofuran, then hydrogen was introduced, heated to 37 ° C and stirred 20 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, suction filtered, steamed and subjected to column chromatography (eluent: dichloromethane / acetone, 10: 1 in volume ratio) and dried in vacuo to give 2.476 g of 5-amino- Bromopyridine in 72percent yield.Iron powder (88g, 1.571mmol), concentrated hydrochloric acid (61mL) and water (287mL) were sequentially added to a solution of 2-bromo-5-nitropyridine (64g, 0.317mol) in ethanol (1L). Iron powder (88 g, 1.571 mmol), concentrated hydrochloric acid (61 mL) and water (287 mL) were sequentially added to a solution of 2-bromo-5-nitropyridine (64 g, 0.317 mol) in ethanol (1 L). 1.1a Synthesis of 5-amino-2-bromopyridine