Bromine → 3-Bromo-2-ethyl-imidazo[1,2-a]pyridine

Reaktionsgleichung

[CH2:1]([C:3]1[N:4]=[C:5]2[CH:10]=[CH:9][CH:8]=[CH:7][N:6]2[CH:11]=1)[CH3:2].[Br:12]Br>C(O)C.O>[Br:12][C:11]1[N:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]2=[N:4][C:3]=1[CH2:1][CH3:2]

Komponenten

Versuchsvorschrift

To a solution of 2-ethyl-imidazo[1,2-a]pyridine (2.17 g, 14.9 mmol) in ethanol (25 mL) was added bromine (2.0 g, 12.5 mmol) in water (5 mL) dropwise at rt. After stirring at rt for 4 h, ethanol was evaporated under reduced pressure. The residue was basified with aqueous sodium bicarbonate and extracted with methylene chloride (3×). The organic phase was washed with brine and dried over anhydrous magnesium sulfate. Concentration followed by flash chromatography eluting with 20% ethyl acetate in hexanes, followed by 50% ethyl acetate in hexanes afforded the title compound (1.88 g) as a viscous oil.