Br[C:2]1[CH:3]=[CH:4][C:5]([O:9][CH3:10])=[C:6]([CH3:8])[CH:7]=1.[Mg].II.[Br:14][C:15]1[CH:16]=[C:17]([C:22](=[O:24])[CH3:23])[CH:18]=[CH:19][C:20]=1[Cl:21]>O1CCCC1>[Br:14][C:15]1[CH:16]=[C:17]([C:22]([C:2]2[CH:3]=[CH:4][C:5]([O:9][CH3:10])=[C:6]([CH3:8])[CH:7]=2)([OH:24])[CH3:23])[CH:18]=[CH:19][C:20]=1[Cl:21]
5-Bromo-2-methoxytoluene (6.4 g, 0.032 mol) was dissolved in tetrahydrofuran (100 mL) and 5 mL of the solution was added to a stirred mixture of magnesium turnings (0.90 g, 0.037 mol) and iodine (a catalytic amount) in tetrahydrofuran (10 mL). The mixture was heated to vigorous reflux until some of the iodine colour was lost. The flask was removed from the heat and the remainder of the bromide was added so as to maintain a gentle reflux. The flask was then returned to the heat and stirred at reflux for 2 hours. The flask was removed from the heat and a solution of 1-(3-bromo-4-chlorophenyl)-ethanone (7.1 g, 0.030 mol) in tetrahydrofuran (100 mL) was added so as to maintain a gentle reflux. The reaction mixture was returned to the heat and stirred at reflux for 3 hours then cooled to room temperature and poured into ice-water (300 mL). The mixture was stirred for 5 minutes then concentrated to remove tetrahydrofuran. The aqueous residue was diluted with aqueous ammonium chloride (100 mL), extracted with ethyl acetate (3 200 mL) and the combined organic extracts were washed with water (100 mL) and brine (100 mL), dried (sodium sulfate) and concentrated to give the crude product as a red oil which was purified by flash chromatography (5 to 10% ethyl acetate/hexane) to give the desired alcohol as a bright yellow oil (6.7 g, 71%). 1H NMR (300 MHz; CDCl3) 7.72 (1H, d, J 2.1, Ar), 7.35 (1H, d, 8.5, Ar), 7.23-7.13 (3H, m, Ar), 6.76 (1H, d, J 8.5, Ar), 3.82 (3H, s, OMe), 2.19 (3H, s, Me), 2.11 (1H, s, OH), 1.88 (3H, s, Me).
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