反应详情

500 mg of 1-(3-amino-1H-indazol-5-yl)-3-(3-methoxybenzyl)urea are suspended in 10 ml of DCM, and 916 μl of BBr3 are added. After two days at RT, the mixture is carefully quenched using 1 ml of methanol and evaporated to dryness. Purification by silica-gel chromatography (eluent: DCM/MeOH 4:1) gives 400 mg of 1-(3-amino-1H-indazol-5-yl)-3-(3-hydroxybenzyl)urea (“A2) as a virtually colourless solid (84%); MS-FAB (M+H+)=298.

1. customthe mixture is carefully quenched
2. customevaporated to dryness
3. customPurification by silica-gel chromatography (eluent: DCM/MeOH 4:1)