C[Mg]Br.C([O:6][CH2:7][CH3:8])C.C(N(CC)CC)C.C(OC(=O)[C:20]1[C:21](=[CH:23][CH:24]=[CH:25][C:26]=1[CH3:27])[OH:22])C.[Cl-].[NH4+]>C1(C)C=CC=CC=1>[OH:22][C:21]1[CH:23]=[CH:24][CH:25]=[C:26]([CH3:27])[C:20]=1[C:7](=[O:6])[CH3:8]A solution of methyl magnesium bromide 3M in diethyl ether (18.5 mL, 55.5 mmol) and triethylamine (6.0 mL, 44.4 mmol) in anhydrous toluene (14 mL) was cooled to 0° C. 6-methylsalicylic acid ethyl ester (2.0 g, 11.1 mmol) in anhydrous toluene (14 mL) was added dropwise and the reaction mixture was stirred at room temperature for 16 hours. A saturated solution of ammonium chloride (10 mL) was added and the mixture was filtered over Celite®. The filtrate was diluted with ethyl acetate (20 mL) and water (10 mL) and layers were separated. The organic layer was washed with brine (10 mL), dried over sodium sulfate and evaporated to dryness. The residue was purified by flash chromatography on silica gel (cyclohexane/ethyl acetate: 9/1) to provide the desired ketone (26a) (1.21 g, 8.0 mmol, 72%).
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