C([O:5][C:6](=[O:17])[CH2:7][O:8][C:9]1[CH:14]=[CH:13][C:12]([F:15])=[CH:11][C:10]=1Br)(C)(C)C.C([O-])([O-])=O.[Na+].[Na+].[F:24][C:25]([F:37])([F:36])[O:26][C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][C:28]=1B(O)O>COCCOC>[F:15][C:12]1[CH:13]=[CH:14][C:9]([O:8][CH2:7][C:6]([OH:5])=[O:17])=[C:10]([C:28]2[CH:29]=[CH:30][CH:31]=[CH:32][C:27]=2[O:26][C:25]([F:24])([F:37])[F:36])[CH:11]=1A solution of (2-bromo-4-fluoro-phenoxy)-acetic acid-t-butyl ester (5.1 g, 16.71 mmol) in DME (60 ml)/2M Na2CO3 (29.25 ml, 58.50 mmol) was treated with 2-trifluoromethoxyphenylboronic acid (5.16 g, 25.08 mmol), and Pd[PPh3]4 (3.87 g, 3.33 mmol) in a microwave oven at 150° C. for 15 min. The reaction mixture was partitioned between 1N HCl and ethyl acetate. The organic layer was successively washed with 1N NaOH and brine, then dried over sodium sulfate, filtered, and concentrated. The crude was absorbed on silica and purified on a silica gel column with a 8-10% ethyl acetate/hexanes gradient to afford 4.65 g of colorless oil (t-butyl ester). This material was dissolved in 4N HCl/dioxane (40 ml) and stirred at 60° C. for 2 h and then at rt overnight. Concentration under reduced pressure afforded the product as colorless oil (4.17 g, 24%).
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