反应详情

To 2-isopropyl-4-methoxycarbonyl-6-aminobenzimidazole in methanol/acetic acid (300 mL, 2:1, v/v) was added N-tert-butoxycarbonyl-4-piperidone (80 g), followed by NaCNBH4 (9 g) at ambient temperature. After stirring at ambient temperature for 1 hour the solvents were removed and the resulting residue was worked up between ethyl acetate and H2O. The organic layer was dried, concentrated, and purified by silica gel chromatography (hexane/ethyl acetate/CH2Cl2 /methanol, gradient) to afford 2-isopropyl-4-methoxycarbonyl-6-(N-(tert-butoxycarbonyl)piperidin-4-ylamino)benzimidazole as a foam.

1. customfollowed by NaCNBH4 (9 g) at ambient temperature
2. customwere removed
3. customThe organic layer was dried
4. concentrationconcentrated
5. custompurified by silica gel chromatography (hexane/ethyl acetate/CH2Cl2 /methanol, gradient)