[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:15](=[O:23])[CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH:12]=[CH:13][CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(NC(C)C)(C)C.[Li].[Br:32]Br.O>O1CCCC1.ClCCl>[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:15](=[O:23])[CH:16]([Br:32])[C:17]2[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=2)[CH:12]=[CH:13][CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1A stirred solution of 1-(3-benzyloxyphenyl)-2-phenylethanone in tetrahydrofuran (30 mL) is treated with a solution of lithium diisopropylamine in tetrahydrofuran (5.5 mL, 2 M) at −35° C. under nitrogen. The resulting clear yellow solution is cooled to −70° C. and treated with a solution of bromine (1.6 g) in dichloromethane (5 mL). Stirring is continued at −70° C. and treated with a solution of bromine (1.6 g) in dichloromethane (5 mL). Stirring is continued at −70° C. for 5 minutes. Water (30 mL) is added and the reaction mixture allowed to warm to room temperature. The reaction mixture is extracted twice with ether (50 mL), the combined extracts are washed with brine (40 mL), dried over magnesium sulphate and evaporated to give (RS)-1-(3-benzyloxyphenyl)-2-bromo-2-phenylethanone (3.92 g) in the form of a yellow oil.
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