Acetone → 5-(5-Bromo-2-ethylphenyl)-4-hydroxycyclopent-2-enone

Participants

Reaction Conditions

Reaction Steps

A solution of (5-bromo-2-ethylphenyl)furan-2-ylmethanol (40.73 g, 145 mmol) in acetone (1150 ml) and water (170 ml) is heated to 55° C. and 30 drops of polyphosphoric acid are added. The mixture is stirred at 55° C. for 44 hours, then cooled to room temperature. The reaction mixture is concentrated under reduced pressure to remove most of the acetone then ethyl acetate (500 ml) is added, and the reaction mixture is partitioned. The aqueous phase is extracted into ethyl acetate and the organic solutions are combined, washed with saturated aqueous sodium bicarbonate solution and brine, dried over anhydrous magnesium sulfate, filtered and the filtrate is concentrated under reduced pressure. The residue is purified by column chromatography on silica gel to give 5-(5-bromo-2-ethylphenyl)-4-hydroxycyclopent-2-enone (33.67 g).

Provenance & Evidence