2-Cyclopenten-1-one → (R)-3-(4-Bromophenyl)cyclopentan-1-one

Participants

Reaction Steps

Under nitrogen stream, 4-bromophenylboric acid (15.7 g, 78 mmol), (R)-BINAP 1.17 g (1.9 mmol), and acetylacetonato bis(ethylene)rhodium(I) (486 mg, 1.9 mmol) were dissolved in a solvent mixture of 1,4-dioxane (150 mL) and water (15 mL), followed by degassing with ultrasonic waves. Subsequently, cyclopentenone (2.6 mL, 31 mmol) was added and the mixture was stirred under reflux with heating for 3 hours. The reaction solution was cooled to room temperature, followed by addition of saturated aqueous sodium bicarbonate solution, and then the solvent was distilled off under reduced pressure. The aqueous phase was extracted with ethyl acetate. The extracted solution was dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue obtained was purified by column chromatography (ethyl acetate/hexane:20/80-30/70) to give the title compound (6.94 g, 91%).

Provenance & Evidence