1H-Isoindol-1-one, 2,3-dihydro-6-hydroxy- (9CI)

22246-66-8

659737-57-2

5-Methoxy-2,3-dihydroisoindol-1-one (167 mg, 1.0 mmol) was used as a starting material, which was dissolved in dichloromethane (8 mL) and cooled to -78°C. Subsequently, boron tribromide (1 M in dichloromethane, 3.6 mL, 3.6 mmol) was added. The reaction mixture was slowly warmed to room temperature and stirred for 18 hours. After the reaction was complete, the mixture was cooled again to -78 °C and methanol (20 mL) was slowly added. After continued stirring at -78 °C for 2 h, the solvent was removed by evaporation. The residue was purified by silica gel column chromatography with the eluent being dichloromethane:2N ammonia methanol solution (9:1) to afford the target product 6-hydroxy-isoindolin-1-one (147 mg, 100% yield) as a white solid. Mass spectrometry analysis showed m/e = 148.0 (M-H+).