反应详情

To a suspension of 4-benzyloxy-1-methyl-2-methylamino-1H-benzimidazole (150 mg) in dichloromethane (2 ml) was added boron tribromide—methyl sulfide complex (211 mg) in dryice-aceton bath, and the mixture was stirred for 1 hour under ice-cooling and then at ambient temperature overnight. To the reaction mixture were added chloroform—methanol (3:1, v/v) and saturated sodium bicarbonate solution, and insoluble material was filtered off. The separated organic layer was concentrated in vacuo. The residue was purified by preparative thin layer chromatography (chloroform:methanol=8:1, v/v) to give 4-hydroxy-1-methyl-2-methylamino-1H-benzimidazole (49 mg).

1. temperaturecooling
2. customat ambient temperature
3. customovernight
4. filtrationv/v) and saturated sodium bicarbonate solution, and insoluble material was filtered off
5. concentrationThe separated organic layer was concentrated in vacuo
6. customThe residue was purified by preparative thin layer chromatography (chloroform