[CH3:1][O:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][C:4]=1[Mg]Br.[CH3:11][C:12]([CH3:20])=[CH:13][C:14](=[O:19])[C:15]([F:18])([F:17])[F:16]>C(OCC)C.[Cu]I>[F:16][C:15]([F:18])([F:17])[C:14](=[O:19])[CH2:13][C:12]([C:4]1[CH:5]=[CH:6][CH:7]=[CH:8][C:3]=1[O:2][CH3:1])([CH3:20])[CH3:11]To a solution of 2-methoxyphenylmagnesium bromide (131 mL, 65.7 mmol, 0.5M solution in THF) at 0° C. was added CuI (12.5 g, 65.7 mmol). The reaction mixture was warmed to room temperature and stirred for 1 hour. A solution of 4-methyl-1,1,1-trifluoropent-3-en-2-one (10.0 g, 65.74 mmol) (made via procedure in PCT international application WO03/082280, Example 10), in diethyl ether (200 mL) was added and the reaction mixture was stirred overnight. The reaction was quenched with saturated aqueous ammonium chloride (50 mL) and extracted with three 300 mL portions of ethyl acetate. The combined organic layers were washed with water and brine, dried over magnesium sulfate, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography using 0%-5% ethyl acetate in hexanes as the eluent. Concentration in vacuo of the product-rich fractions gave 14 g (82%) of 1,1,1-trifluoro-4-(2-methoxyphenyl)-4-methylpentan-2-one.
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