[O:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[CH:3]=[C:2]1[Si](C)(C)C.[Br:14][C:15]1[CH:20]=[CH:19][C:18]([CH2:21][C:22](Cl)=[O:23])=[CH:17][CH:16]=1>C(Cl)Cl.Cl[Ti](Cl)(Cl)Cl>[O:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[CH:3]=[C:2]1[C:22](=[O:23])[CH2:21][C:18]1[CH:19]=[CH:20][C:15]([Br:14])=[CH:16][CH:17]=1Benzofuran-2-yl-trimethyl-silane (3.4 g, 17.86 mmol) was dissolved in methylene chloride (40 mL) and cool to −78° C. 4-Bromophenyl-acetyl chloride (19.65 mmol, 1.1 equiv.) was added at this temperature. Under vigorous stirring, a solution of TiCl4 (23 mL, 1M, 23.2 mmol, 1.3 equiv.) in CH2Cl2 was added dropwise and stirring continued for 20 min. Then the reaction was quenched with H2O (100 mL), cooling bath was removed and the mixture was allowed to warm up to room temperature. It was then diluted with H2O (100 mL) and extracted with CH2Cl2 (3×). Organic layers were combined, washed with brine, dried over MgSO4, solvent evaporated. Crude product thus obtained was subject to column purification. (silica gel, 10% EtOAC/Hexane). 980 mg of 1-Benzofuran-2-yl-2-(4-bromo-phenyl)-ethanone was obtained in 17% yield.
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