反应详情

A stirred solution of 2-butyl-1-[(2'-carboxybiphenyl-4-yl)methyl]benzimidazole (1.50 g) in benzene (30 ml) was added dropwise to sodium dihydro-bis(2-methoxyethoxy)aluminate (70% toluene solution). The mixture was stirred for one hour at room temperature, and then heated for 10 minutes under reflux. The reaction mixture was cooled and poured into 2N-HCl, followed by extraction with dichloromethane. The extract was washed with water and dried (MgSO4), and the solvent was evaporated in vacuo. The residue was purified by silica gel (80 g) column chromatography to give the title compound (0.67 g, 46%) as an oil, which was crystallized from ethyl acetate-ether to afford pale yellow prisms, m.p.162°-163° C.

1. temperatureheated for 10 minutes
2. temperatureunder reflux
3. temperatureThe reaction mixture was cooled
4. extractionfollowed by extraction with dichloromethane
5. washThe extract was washed with water
6. dry with materialdried (MgSO4)
7. customthe solvent was evaporated in vacuo
8. customThe residue was purified by silica gel (80 g) column chromatography