N-bromobutanimide → 3-Bromo-8-chloro-1-(4-phenoxy-phenyl)-imidazo[1,5-a]pyrazine

Participants

Reaction Steps

To a solution of 8-chloro-1-(4-phenoxy-phenyl)-imidazo[1,5-a]pyrazine (2.10 g, 6.5 mmol) in DMF (12 mL) at 0° C. was added NBS (1.40 g, 7.84 mmol) and stirred for 2 h. DMF was removed under pressure and added water (75 mL). Solid formed was extracted with EtOAc (3×50 mL), washed with water (40 mL) and dried (Na2SO4). Evaporation of solvent gave crude material, which was purified by column chromatography on silica gel using CH2Cl2/MeOH (98:2). Yield: 2.05 g (77%); 1H NMR (CDCl3, 300 MHz) δ 7.11-7.21 (m, 5H), 7.28-7.32 (m, 3H), 7.61-7.64 (m, 2H), 7.70 (d, J=2.4 Hz, 1H).

Provenance & Evidence