[C:1]1([Mg]Br)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[CH2:9]([CH:11]1[O:13][CH2:12]1)[Br:10].O.CC(C)=O.OS(O)(=O)=O.O=[Cr](=O)=O>CCOCC.CC(C)=O>[Br:10][CH2:9][C:11]([CH2:12][C:1]1[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1)=[O:13]To a suspension of CuBr (0.143 g, 0.997 mmol) in 25 mL dry ether was slowly added 1M phenylmagnesium bromide (10 mL, 10 mmol). Epibromohydrin (0.87 mL, 10.5 mmol) was then added dropwise. The reaction mixture was allowed to stir at −78° C. to room temperature overnight, poured into H2O and extracted with ether. The extracts were washed with H2O and brine, dried over Na2SO4, filtered and evaporated in vacuo. The crude alcohol thus obtained was dissolved in acetone (400 mL) and chilled in ice, and to this solution was added dropwise 6 mL of Jones reagent (prepared by dissolution of 2.67 g CrO3 in 2.5 mL H2SO4, followed by dilution with H2O to 10 mL). The reaction mixture was stirred at 0° C. for 15 min and was then evaporated in vacuo. The residue was taken up in ethyl acetate, washed repeatedly with water and once with brine, dried over Na2SO4, filtered and evaporated to afford the ketone product as a brown oil (1.6 g, 75%). 1H NMR (DMSO-d6) δ 7.17-7.35 (m, 5H), 4.45 (s, 2H), 3.94 (s, 2H); MS (DCI+) m/z 230 (M+NH4+).
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