反应详情

6-t-Butoxycarbonylamino-1-(2-chlorobenzyl)-2-n-propylbenzimidazole (700 mg) (example 1) is dissolved in a mixture solvent of methylene chloride (10 ml) and trifluoroacetic acid (1 ml), and the solution is stirred for five hours at room temperature. A small amount of methylene chloride is added into the reaction solution, and the solution is washed with sodium carbonate aqueous solution. After it is dried, the solvent is removed through evaporation. The residue is crystallized using a mixture solvent of normal hexane and ether, and 6-amino-1-(2-chlorobenzyl)-2-n-propylbenzimidazole (455 mg) is obtained. 1H-NMR (CDCl3, δ): 1.01 (3H, t, J=7.5 Hz), 1.86 (2H, m), 2.73 (2H, t, J=7.5 Hz), 5.30 (2H, s), 6.41 (1H, d, J=1.5 Hz), 6.48 (1H, d, J=7.5 Hz), 6.66 (1H, dd, J=7.5 and 1.5 Hz), 7.10 (1H, t, J=7.5 Hz), 7.25 (1H, t, J=7.5 Hz), 7.46 (1H, d, J=7.5 Hz), 7.57 (1H, d, J=7.5 Hz).

1. washthe solution is washed with sodium carbonate aqueous solution
2. customAfter it is dried
3. customthe solvent is removed through evaporation
4. customThe residue is crystallized