Reaktion #708019

Reaktionsgleichung

sodium hydroxide

2-(2,4-dimethoxyphenyl)-4-methyl-5-(3-pyridyl)imidazole

hydrogen bromide

→

2-(5-bromo-2,4-dimethoxyphenyl)-4-methyl-5-(3-pyridyl)imidazole

Lösungsmittel

acetic acid

acetic acid

pyridinium hydrobromide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted with chloroform
2. 2
   WaschenThe organic layer was washed by aqueous sodium bicarbonate
3. 3
   Sonstigeevaporated
4. 4
   Sonstigethe residue was triturated in diisopropyl ether

Vorschrift

To a solution of 2-(2,4-dimethoxyphenyl)-4-methyl-5-(3-pyridyl)imidazole (1.0 g) in acetic acid (10 ml) were added a solution of hydrogen bromide in acetic acid (28%, 0.2 ml) and pyridinium hydrobromide perbromide (1.49 g), and was stirred at ambient temperature for 19 hours. Then the mixture was poured into ice-water (100 ml), adjusted to pH 4.8 with 8N sodium hydroxide, and extracted with chloroform. The organic layer was washed by aqueous sodium bicarbonate and evaporated, and the residue was triturated in diisopropyl ether to give 2-(5-bromo-2,4-dimethoxyphenyl)-4-methyl-5-(3-pyridyl)imidazole (0.92 g).

Quelle