3-Hydroxybenzamide

873-62-1

618-49-5

General procedure for the synthesis of 3-hydroxybenzamide from 3-hydroxybenzonitrile: 3-cyanophenol (295 mg, 2.48 mmol, 100 mol%) and sodium perborate tetrahydrate (NaBO3-4H2O, 1146 mg, 7.45 mmol, 300 mol%) were dissolved in water (8 mL) and heated to 50 °C. Methanol (14 mL) was then added slowly until the mixture became clear. The reaction mixture was stirred continuously at 50 °C for 70 hours. After completion of the reaction, excess methanol was removed by evaporation. The pH of the remaining mixture was adjusted with dilute hydrochloric acid (aq) to 5. Extraction was carried out with dichloromethane (12 mL) and ethyl acetate (5 x 15 mL). The organic phases were combined, washed with brine (25 mL) and dried over anhydrous sodium sulfate (Na2SO4). After filtration, the solvent was evaporated to give the target product, 3-hydroxybenzamide (49a), as a spectroscopically pure white solid (183 mg, 54% yield): melting point 165-168 °C; thin-layer chromatography Rf value (50% ethyl acetate/hexane) 0.10.