General procedure for the synthesis of (3-bromothiophen-2-yl)methanol from 3-bromothiophene-2-carboxaldehyde: 3-bromothiophene-2-carboxaldehyde (500 mg, 2.62 mmol) was dissolved in methanol (10 mL) at 0 °C, sodium borohydride (169 mg, 4.47 mmol) was added in batches, and the reaction mixture was stirred and reacted at 0 °C for 2 hours. After completion of the reaction, the solvent was removed by rotary evaporation. The residue was separated by extraction with ethyl acetate (20 mL) and 10% ammonium chloride solution (10 mL). The organic layer was washed with water (10 mL), dried over anhydrous sodium sulfate, filtered and concentrated to give (3-bromothiophen-2-yl)methanol (505 mg, 2.62 mmol, 100% yield) as a yellow oil.
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