3,5-DIFLUORO-4-HYDROXY-BENZONITRILE

960287-97-2

2967-54-6

The general procedure for the synthesis of 3,5-difluoro-4-hydroxybenzonitrile from 3,5-difluoro-4-hydroxybenzaldehyde oxime is as follows: to a solution of tetrahydrofuran (THF, 10 mL) containing the aldoxime (0.01 mol) was added T3P (15 mol%, 50% solution in ethyl acetate (EtOAc)). The reaction mixture was stirred at room temperature for 1-2 h under nitrogen protection. The progress of the reaction was monitored by thin layer chromatography (TLC) and after confirming the completion of the reaction, the solvent was removed under reduced pressure. The residue was diluted with distilled water (20 mL) and subsequently extracted with ethyl acetate (2 x 20 mL). The organic phases were combined and washed sequentially with saturated sodium bicarbonate (NaHCO3) solution (10 mL) and brine. The organic phase was dried over anhydrous sodium sulfate (Na2SO4) and concentrated under reduced pressure to afford the target product 3,5-difluoro-4-hydroxybenzonitrile of high purity.