Hydrogen Bromide → 1,1,1-Trifluoro-4-(4-hydroxyphenyl)butan-2-one

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Reaction Conditions

Reaction Steps

A 100 mL round bottom flask, fitted with reflux condenser, magnetic stirrer and argon inlet was charged with 2.05 g (6.7 mmol) of ethyl 2-(4-methoxybenzyl)-3-oxo-4,4,4-trifluorobutanoate (I), 20 mL of 31% (w/v) hydrogen bromide in acetic acid, and 10 mL of water. This mixture was heated overnight at 120° C., cooled, concentrated under reduced pressure and partitioned between dichloromethane and water. The organic layer was extracted sequentially with aqueous bisulfite, and saturated sodium bicarbonate, and then dried over anhydrous magnesium sulfate. Solvent was removed under reduced pressure. The crude reaction mixture was chromatographed on a 50 mm×300 mm silica gel column with ethyl acetate/hexane (50/50). Similar fractions were combined and the solvent was removed under reduced pressure to yield 600 mg (41%) as a clear oil. NMR(CDC13): 2.95(m,4H), 5.40(bs, 1H), 6.93(dd,4H) J=4, 60 Hz.

Provenance & Evidence