Boron tribromide → 1,1,1-Trifluoro-4-(4-hydroxyphenyl)butan-2-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 1,1,1-trifluoro-4-[4-methoxyphenyl]-2-butanone (43.5 g, 0.187 mol) in dichloromethane (500 ml) at −78° C. (dry ice-acetone) was added dropwise boron tribromide (53 ml, 0.561 mol). The mixture was then stirred at 0° C. (ice bath) for 3 h, and cautiously quenched by dropwise addition of ice-water (200 ml) over a period of 1 h. The aqueous phase was saturated with solid sodium chloride, extracted with dichloromethane (500 ml) followed by diethyl ether (500 ml). The combined organic layers were dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was purified by bulb-to-bulb distilation (96-100° C., 0.2 mmHg) to afford the title compound (34.4 g, 84%) as a yellow liquid which solidified upon standing.

Provenance & Evidence