General procedure for the synthesis of 3,5-difluoro-4-(hydroxymethyl)benzonitrile from 4-cyano-2,6-difluorobenzaldehyde: 2,6-difluoro-4-formylbenzonitrile (1.36 g, 8.13 mmol) was dissolved in 25 mL of methanol and cooled in an ice bath. Under stirring conditions, sodium borohydride (0.307 g, 8.42 mmol) was added in batches and the reaction lasted for 65 min. Upon completion of the reaction, the solvent was removed by evaporation and the residue was partitioned between ether and aqueous sodium bicarbonate. The ether layer was subsequently washed with aqueous sodium bicarbonate and brine, dried over anhydrous sodium sulfate, and then the solvent was evaporated. The crude product crystallizes rapidly and can be used directly without further purification. Yield: 1.24 g (90%). 1H NMR (400 MHz, CDCl3) δ 7.24 (m, 2H), 4.81 (s, 2H), 2.10 (wide, 1H).
