2,4-Difluorobenzyl bromide

• novel 1,2,4-triazolium derivatives
• 1,5-biaryl pyrrole EP₁ receptor antagonists

56456-47-4

23915-07-3

The general procedure for the synthesis of 2,4-difluorobenzyl bromide from 2,4-difluorobenzyl alcohol was as follows: to a solution of diethyl ether (10 mL) of 2,4-difluorobenzyl alcohol (450 mg, 3.12 mmol) was slowly added phosphorus tribromide (0.2 mL, 2.18 mmol) at 0 °C. The reaction mixture was stirred at room temperature for 2 hours. Upon completion of the reaction (monitored by thin layer chromatography), the reaction was quenched with ice water (20 mL) and extracted with ethyl acetate (2 x 20 mL). The organic layers were combined, washed sequentially with water (40 mL) and saturated saline (40 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give the crude product. Purification by silica gel column chromatography with 5% ethyl acetate/hexane as eluent gave 2,4-difluorobenzyl bromide (420 mg, 2.02 mmol, 65% yield) as a colorless liquid.1H NMR (200 MHz, CDCl3): δ 7.43-7.31 (m, 1H), 6.92-6.77 (m, 2H), 4.48 (s, 2H).