To a suspension (200 mL) of 60% sodium hydride (1.8 g) in tetrahydrofuran was added dropwise a solution (50 mL) of ethyl 3-oxohexanoate (10.9 g) in tetrahydrofuran at 0° C. The mixture was stirred at the same temperature for 30 min, 4′-(bromomethyl)-2′-fluorobiphenyl-2-carbonitrile (10.0 g) was added, and the mixture was stirred at room temperature for 16 hr. The reaction mixture was poured into 1 N hydrochloric acid, and the mixture was extracted with ethyl acetate. The obtained ethyl acetate layer was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated. The residue was purified by silica gel column chromatography to give the title compound as a pale-yellow oil (12.9 g, 100%).
