Potassium Carbonate → HCID 66778352, Verbindung

To a solution (25 mL) of 1-(2-fluoro-6-hydroxyphenyl)ethanone (1.3 g) in N,N-dimethylformamide were added potassium carbonate (3.5 g) and 1-bromo-3-methylbutan-2-one (1.7 g) synthesized in Example A75(1) at room temperature, and the mixture was stirred at room temperature for 3 hr. The reaction mixture was allowed to cool to room temperature, and filtered through celite. Water was added to the filtrate, and the mixture was extracted with diethyl ether. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The obtained residue was dissolved in N,N-dimethylformamide (15 mL) again, 1,8-diazabicyclo[5.4.0]undec-7-ene (1.3 mL) was added to the mixture, and the mixture was stirred at 110° C. for 1 hr with heating. After cooling to room temperature, the reaction mixture was quenched with 1N hydrochloric acid, and the mixture was extracted with diethyl ether. The extract was concentrated under reduced pressure, and the precipitated compound was recrystallized from diisopropyl ether-hexane to give the title object compound (1.4 g, 77%) as a colorless solid.