Bromine → 3-Bromo-2-ethyl-imidazo[1,2-a]pyridine
反応式
[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>CCO.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]参加物
5
実験手順
To a solution of 2-ethyl-imidazo[1,2-a]pyridine (2.17 g, 14.9 mmol) in EtOH (25 mL) was added Br2 (2.0 g, 12.5 mmol) in H2O (5 mL) dropwise at rt. After stirring at rt for 4 h, EtOH was evaporated under reduced pressure. The residue was basified with aqueous NaHCO3 and extracted with CH2Cl2 (3×). The organic phase was washed with brine and dried over anhydrous MgSO4. Concentration followed by flash chromatography chromatography eluting with 20% EtOAc in hexanes, followed by 50% EtOAc in hexanes afforded the title compound (1.88 g) as a viscous oil. 1H NMR (500 MHz, CDCl3): δ 1.36 (t, J=7.5 Hz, 3H), 2.83 (q, J=7.6 Hz, 2H), 6.88 (t, J=6.8 Hz, 1H), 7.20 (m, 1H), 7.55 (dd, J=8.9, 0.9 Hz, 1H), 8.05 (dd, J=6.9, 1.2 Hz, 1H).