[Br:1][C:2]1[CH:3]=[C:4]([CH:12](O)[CH3:13])[CH:5]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:7]=1.C(Br)(Br)(Br)[Br:16].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>O1CCCC1.CCCCC>[Br:1][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[C:4]([CH:12]([Br:16])[CH3:13])[CH:3]=1To a solution of (±)-1-(3-bromo-5-(trifluoromethyl)phenyl)ethanol (390 mg, 1.45 mmol) and carbon tetrabromide (577 mg, 1.74 mmol) in tetrahydrofuran (2 mL) at 0° C. was added triphenylphosphine (456 mg, 1.74 mmol). The resulting solution was stirred at room temperature for 2 h. The reaction was treated with an additional portion of carbon tetrabromide (289 mg, 0.87 mmol)) and triphenylphosphine (228 mg, 0.87 mmol). The reaction was stirred at room temperature for 1 h, diluted with several volumes of pentane, and filtered to remove undissolved solids. The organics were concentrated and purified by column chromatography (1→3% ethyl acetate/hexanes) to give 439 mg (91%) as a colorless oil. 1H NMR (500 MHz, CDCl3) δ ppm 7.76 (s, 1H), 7.68 (s, 1H), 7.60 (s, 1H), 5.12 (q, J=7.0 Hz, 1H), 2.03 (d, J=7.0 Hz, 3H); 13C NMR (126 MHz, CDCl3) δ ppm 146.4, 133.5, 132.9 (q, J=32.6 Hz), 128.4 (q, J=3.8 Hz), 123.0, 123.0 (q, J=273 Hz), 122.6 (q, J=3.8 Hz), 46.1, 26.6.
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