P(Br)(Br)[Br:2].[O:5]([C:12]1[CH:19]=[CH:18][CH:17]=[CH:16][C:13]=1[CH2:14]O)[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.O>O1CCOCC1>[O:5]([C:12]1[CH:19]=[CH:18][CH:17]=[CH:16][C:13]=1[CH2:14][Br:2])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1Phosphorus tribromide (5.5 ml, 57.1 mmol) was added dropwise over a period of 10 min to a solution of 2-phenoxybenzylalcohol (4.08 g, 20.4 mmol) in dioxane (165 ml). The reaction mixture was stirred for 40 min. Another portion of phosphorus tribromide (5.5 ml, 57.1 mmol) was added. The reaction mixture was stirred for 56 hours at room temperature. It was cooled to 0° C. Water (45 ml) was added carefully. The reaction mixture was stirred for 30 min at room temperature. The mixture was extracted with ethyl acetate (100 ml). The ethyl acetate phase was washed with 1 N hydrochloric acid. The combined aqueous layers were extracted with ethyl acetate. The combined organic layers were washed with a saturated aqueous soludtion of sodium hydrogen carbonate (100 ml) and dried over magnesium sulphate. The solvent was removed in vacuo. The crude product was purified by flash chromatography on silica (90 g), using ethyl acetate/heptane (1:3) as eluent, to give 4.80 g of 2-phenoxybenzyl bromide.
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