Br[C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]([O:11][CH2:12][CH3:13])=[O:10])=[C:4]([O:14][CH:15]2[CH2:20][CH2:19][CH2:18][CH2:17][CH2:16]2)[CH:3]=1.CC1(C)C(C)(C)[O:25][B:24](B2OC(C)(C)C(C)(C)O2)[O:23]1.C([O-])(=O)C.[K+].Cl>O1CCOCC1.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[CH:15]1([O:14][C:4]2[CH:3]=[C:2]([B:24]([OH:25])[OH:23])[CH:7]=[CH:6][C:5]=2[CH2:8][C:9]([O:11][CH2:12][CH3:13])=[O:10])[CH2:20][CH2:19][CH2:18][CH2:17][CH2:16]1To a solution of ethyl (4-bromo-2-cyclohexyloxyphenyl)acetate (1.23 g) in 1,4-dioxane (14.6 ml) were added 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane (1.01 g), dichlorobis(triphenyphosphine)palladium(II) (126 mg) and potassium acetate (1.06 g) at room temperature under nitrogen, and the mixture was stirred at 95° C. for 2 hours. The resulting mixture was poured into 1N hydrochloric acid and the aqueous layer was extracted with a mixture of hexane and ethyl acetate (1:1). The organic layer was washed successively with water and brine, dried over anhydrous magnesium sulfate, evaporated and dried in vacuo. To a suspension of the above obtained residue in a mixture of ethyl acetate (14.6 ml) and water (24.6 ml) were added ammonium acetate (1.75 g) and sodium periodate (4.86 g) at room temperature, and the mixture was stirred at the same temperature for 24 hours. The resulting mixture was poured into dilute hydrochloric acid and the aqueous layer was extracted with ethyl acetate. The organic layer was washed successively with water and brine, dried over anhydrous magnesium sulfate and evaporated under reduced pressure. The residue was purified by column chromatography on silica gel (hexane/ethyl acetate=2:1 to 1:1) to give [3-cyclohexyloxy-4-(ethoxycarbonylmethyl)phenyl]boronic acid (719 mg).
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