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ChemicalBook CAS DataBase List 3-Bromo-2-hydroxypyridine
13466-43-8

3-Bromo-2-hydroxypyridine synthesis

4synthesis methods
3-Bromo-2-pyridinamine

13534-99-1

3-Bromo-2-hydroxypyridine

13466-43-8

The general procedure for the synthesis of 3-bromo-2-hydroxypyridine from 2-amino-3-bromopyridine was as follows: sodium nitrite (24.2 g, 0.35 mol, 4.84 eq.) was dissolved in water (175 mL) at 0 °C and slowly added dropwise to a solution containing 2-amino-3-bromopyridine (12.5 g, 72.4 mmol) and sulfuric acid (35 mL, 0.66 mol , 9.10 eq.) in a solution of water (175 mL). The reaction mixture was stirred at 0 °C for 1 hour. Subsequently, the reaction mixture was neutralized with sodium hydroxide solution to pH=7. The neutralized solution was extracted with chloroform (3 x 200 mL), the organic phases were combined and washed with brine (200 mL), dried over magnesium sulfate, filtered and concentrated in vacuum to afford the milky white solid product 3-bromo-2-hydroxypyridine (11.3 g, 90% yield). The product was characterized as follows: melting point 183 °C; IR (pure) νmax 3339, 3105, 2991, 2942, 1776, 1650, 1610, 1464 cm-1; 1H NMR (500 MHz, CDCl3) δ 7.87 (dd, J = 7.3, 1.9 Hz, 1H), 7.49 (dd, J = 6.4, 1.9 Hz, 1H), 6.24 (dd, J = 7.3, 6.4 Hz, 1H) ppm; 13C NMR (125 MHz, CDCl3) δ 161.9, 143.9, 134.4, 115.7, 107.7 ppm; HRMS (ESI) m/z [M + Na]+ Calculated value: 195.9369, measured value: 195.9373 (deviation +2.07 ppm).

-

Yield:13466-43-8 78%

Reaction Conditions:

with bromine;potassium bromide in water at 20; for 24.25 h;

Steps:

1.V.T77-1 Step T77-1.
3-l3romo-pyridin-2-ol. A stirred suspension of 2-pyridone (77-0, 19 g, 200 mmol) in 200 mE of 1 M aqueous K13r at room temperature was treated over 15 mm with bromine (32 g, 200 mmol; CAUTION: Large quantities of 13r2 should be handled careffilly) in 200 mE of 1 M aqueous K13r, then stirred vigorously at room temperature 0/N. After 24 h, this solution deposited crystals which were filtered off and then recrystallized from acetonitrile to give 27.2 g (78%) of 3-bromo- pyridin-2-ol. (77-1) [J. Am. Chem. Soc. 1982, 104, 4142- 4146; Bioorg. Med. Chem. Lett. 2002, 12, 197-200; JMed Chem. 1979, 22, 1284-1290.] Molecular weight calcd. for C5H4I3rNO: 173; (M+H) found: 174

References:

Ocera Therapeutics, Inc.;Hoveyda, Hamid R.;Fraser, Graeme L.;Peterson, Mark US2018/110824, 2018, A1 Location in patent:Paragraph 0497; 0498; 0499

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