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[CH:27]=[CH:26][C:25]2[C:20](=[CH:21][CH:22]=[CH:23][CH:24]=2)[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.COCCOC.O>[Br:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=1[C:18]1[CH:27]=[CH:26][C:25]2[C:20](=[CH:21][CH:22]=[CH:23][CH:24]=2)[CH:19]=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, and then potassium carbonate (6.67 g, 48.3 mmol, 3 equiv), 2-bromophenylboronic acid (3.80 g, 18.9 mmol, 0.98 equiv) and 2-bromonaphthalene (4.00 g, 19.3 mmol, 1 equiv) were added. The flask was 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 7 hours. After cooling to room temperature, the phases were partitioned and the organic layer was collected. The aqueous layer was washed with ethyl acetate (3×30 mL), and the combined organic fractions were washed with brine (60 mL), dried over sodium sulfate, filtered, and concentrated on a rotary evaporator. The crude orange oil was purified by column chromatography on an Isco CombiFlash system (120-g column; gradient: 0.5 column volumes heptane, ramp up to 99:1 heptane:dichloromethane over 0.5 column volumes, hold at 99:1 for 1 column volumes, ramp up to 92:8 heptane:dichloromethane over 7 column volumes, hold at 92:8 for 6 column volumes) to afford the title compound as a colorless oil (4.26 g, 97 area % by HPLC, 78% yield). 1H NMR (400 MHz, CDCl3) δ ppm 7.93-7.85 (m, 4H), 7.72 (dd, J=8.0, 1.0 Hz, 1H), 7.57 (dd, J=8.5, 1.7 Hz, 1H), 7.55-7.49 (m, 2H), 7.46-7.38 (m, 2H), 7.28-7.21 (m, 1H).
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