C(=O)([O-])[O-].[K+].[K+].[Br:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=1B(O)O.Br[C:18]1[C:27]2[C:22](=[CH:23][CH:24]=[CH:25][CH:26]=2)[CH:21]=[CH:20][CH:19]=1.N#N.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>C([O-])(=O)C.[Pd+2].C([O-])(=O)C.C(O)C.COCCOC.O>[Br:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=1[C:26]1[C:27]2[C:22](=[CH:21][CH:20]=[CH:19][CH:18]=2)[CH:23]=[CH:24][CH:25]=1
To a 250-mL round bottom flask equipped with a magnetic stir bar was added water (25 mL) and 1,2-dimethoxyethane (25 mL). The solution was sparged with nitrogen for 20 minutes, then potassium carbonate (6.67 g, 48.3 mmol, 3 equiv), 2-bromophenylboronic acid (3.80 g, 18.9 mmol, 0.98 equiv) and 1-bromonaphthalene (2.70 mL, 19.3 mmol, 1 equiv) were added. The flask was then purged with N2 for 10 minutes before finally adding palladium(II) acetate (87 mg, 0.39 mmol, 0.02 equiv) and triphenylphosphine (405 mg, 1.55 mmol, 0.08 equiv). The reaction mixture was heated to 85° C. under a positive pressure of nitrogen for 16 hours. After cooling to room temperature, the phases were partitioned and the organic layer was collected, and the aqueous layer was washed with ethyl acetate (3×20 mL). The combined organic fractions were washed with brine (50 mL), dried over sodium sulfate, filtered, and concentrated on a rotary evaporator. The crude material was purified by column chromatography on an Isco CombiFlash system (120-g column; gradient: ramp up from heptane to 99:1 heptane:ethyl acetate over 1.5 column volumes, hold at 99:1 for 1.5 column volumes, ramp up to 92:8 heptane:ethyl acetate over 6 column volumes, hold at 92:8 for 6 column volumes) and then recrystallization from 99:1 heptane:ethanol to afford the title compound as a white solid (2.81 g, 93 area % by HPLC, 51% yield). 1H NMR (400 MHz, CDCl3) δ ppm 7.91 (dd, J=8.3, 0.8 Hz, 2H), 7.74 (dd, J=8.0, 1.2 Hz, 1H), 7.57-7.29 (m, 8H)
読み込み中…
