The general procedure for the synthesis of 4-(4-bromo-3-(hydroxymethyl)phenoxy)benzonitrile from 4-(4-bromo-3-formylphenoxy)benzonitrile was as follows: 100 g of 4-(4-bromo-3-formylphenoxy)benzonitrile (VI) was dissolved in 500 mL of methanol at 25-30 °C, and subsequently cooled to 10-15 °C. While maintaining 10-15 °C, 6.2 g of sodium borohydride was slowly added for 60-90 min. After the addition was completed, the temperature of the reaction system was slowly increased to 15-20°C. Upon completion of the reaction, 1000 mL of water was added to the reaction mixture and stirred at 25-30 °C for 1 hour. The resulting solid product was collected by vacuum filtration, washed with water and dried under vacuum at not more than 55 °C to obtain 4-(4-bromo-3-(hydroxymethyl)phenoxy)benzonitrile (V). Yield: 99.0%; purity: 99.02%.
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