Hydrochloric Acid → 3-Allyl-2-norbornanone

Temperature

-20 °C

To 3.4 ml (6.8 mmol) of a 2M solution of lithium diisopropyl amide in tetrahydrofuran-hexane, 1 ml of a solution of 500 mg (4.54 mmol) of (-)-2-norbornanone in tetrahydrofuran was added dropwise at -40° C., and the mixture was stirred at -20° C. for 10 minutes. Then, 1 ml of a solution of 540 mg (4.46 mmol) of allyl bromide in tetrahydrofuran was added dropwise, the mixture was stirred at -20° C. for 30 minutes, the temperature of the mixture was raised to room temperature, and the mixture was stirred for one hour. On ice cooling, the reaction mixture was poured into 20 ml of 1N hydrochloric acid, and the mixture was extracted with toluene (50 ml×4). The extract was washed with successive, saturated sodium bicarbonate solution, water, saturated sodium chloride (each 50 ml), and dried over anhydrous magnesium sulfate. The solution was filtered, and the solvent was distilled off to obtain 980 mg of crude 3-allyl-2-norbornanone. The product was purified by distillation, and 550 mg (3.66 mmol) of (-)-exo-3-allyl-2-norbornanone was obtained. Yield: 81%.

1. stirringthe mixture was stirred at -20° C. for 30 minutes
2. temperaturethe temperature of the mixture was raised to room temperature
3. stirringthe mixture was stirred for one hour
4. extractionthe mixture was extracted with toluene (50 ml×4)
5. washThe extract was washed with successive, saturated sodium bicarbonate solution, water, saturated sodium chloride (each 50 ml), and
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationThe solution was filtered
8. distillationthe solvent was distilled off

ORD record

ord-35e6151db3f24a4a9691d0b55166a66a

Source dataset

uspto-grants-1993_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05266728