Br[C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[C:4]([O:10][CH2:11][CH:12]2[CH2:14][CH2:13]2)[CH:3]=1.C([Li])(CC)C.C(O[B:24]1[O:28][C:27]([CH3:30])([CH3:29])[C:26]([CH3:32])([CH3:31])[O:25]1)(C)C.[Cl-].[NH4+]>O1CCCC1>[CH:12]1([CH2:11][O:10][C:4]2[CH:3]=[C:2]([B:24]3[O:28][C:27]([CH3:30])([CH3:29])[C:26]([CH3:32])([CH3:31])[O:25]3)[CH:7]=[CH:6][C:5]=2[O:8][CH3:9])[CH2:14][CH2:13]1
To 60 ml of dehydrated tetrahydrofuran solution containing 3.64 g (14.2 mmol) of 4-bromo-2-cyclopropylmethoxy-1-methoxybenzene was added dropwise 18.0 ml of tetrahydrofuran solution containing 0.97M sec-butyl lithium at −70° C. under argon atmosphere, and the mixture was stirred at the same temperature for 50 minutes. Then, 3.70 ml (19.2 mmol) of 2-isopropoxy-4,4,5,5-tetramethyl-[1,3,2]-dioxaborolane was added to the mixture, and the resulting mixture was raised to room temperature. After completion of the reaction, a saturated aqueous solution of ammonium chloride was added to the reaction mixture, and after adjusting a pH thereof to 2 with 1N hydrochloric acid, the mixture was extracted with ethyl acetate. The organic layer after separation was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, and then, concentrated under reduced pressure to obtain 4.78 g (purity: 84.7%) of the title compound as a slightly yellowish oil. (Yield: 94%)
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