[F:1][C:2]1[CH:21]=[CH:20][C:5]([CH2:6][CH2:7][C:8]2[CH:17]=[CH:16][C:15]([CH2:18]O)=[CH:14][C:9]=2[C:10]([O:12][CH3:13])=[O:11])=[CH:4][CH:3]=1.C(Br)(Br)(Br)[Br:23].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>ClCCl>[F:1][C:2]1[CH:21]=[CH:20][C:5]([CH2:6][CH2:7][C:8]2[CH:17]=[CH:16][C:15]([CH2:18][Br:23])=[CH:14][C:9]=2[C:10]([O:12][CH3:13])=[O:11])=[CH:4][CH:3]=1A mixture of methyl 2-(4-fluorophenethyl)-5-hydroxymethylbenzoate (13.10 g., 45.43 mmol), carbon tetrabromide (18.08 g, 54.52 mmol) and triphenylphosphine (14.30 g, 54.52 mmol) in dichloromethane (400 ml) was stirred at ambient temperature for 4 hours. More carbon tetrabromide (7.54 g, 23.00 mmol) and triphenylphosphine (5.96 g, 23.00 mmol) in dichloromethane (50 ml) were added and then stirred for a further 2 hours. The reaction was applied directly to a silica flash column and eluted with iso-hexane/ethyl acetate (92.5:7.5) to give as a clear gum methyl 2-(4-fluorophenethyl)-5-bromomethylbenzoate (9.30 g).
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