反应详情

A mixture of 1H-benzimidazol-5-amine (0.8 g, 6 mmol), 2,6-dichloropyrazine (0.9 g, 6.0 mmol) and cesium carbonate (2.73 g, 8.4 mmol) in DMF (6 mL) was heated under N2 for 6 h. Upon cooling to RT the mixture was diluted with dichloromethane-methanol (6:1, 30 mL) and filtered and the filtrate concentrated in vacuo. The residue was chromatographed using CH2Cl2-MeOH (98:2-94:6) to give from the less polar fractions 1-(6-chloropyrazin-2-yl)-1H-benzimidazol-6-amine (398 mg):

1. temperaturewas heated under N2 for 6 h
2. filtrationfiltered
3. concentrationthe filtrate concentrated in vacuo
4. customThe residue was chromatographed