反应详情

A solution of commercially available 1-cyclohex-1-enylpyrrolidine 1(5 g, 99.2 mmol) and propyl bromide (36 mL, 4 eq) in benzene was refluxed at 90° C. for overnight. Another 4 eq of propyl bromide (36 mL) was added and refluxing was continued for overnight. The reaction mixture was cooled to room temperature. 30 mL of water was added, and the resulting solution refluxed for 1 hour. After cooling to room temperature, 30 mL of 1M H2SO4 was added and the solution stirred for 10 minutes. The mixture was extracted with ether, and the combined organic extracts were washed with NaHCO3, H2O, brine, and dried over MgSO4. Purification by column chromatography using EtOAc/hex (1:3) as eluant afforded 2.12 g (15.3%) of 2-propylcyclohexanone. Spectroscopic data: 1H NMR (CDCl3, 300 MHz) δ=0.90 (t, 3H, J=7.035 Hz), 1.14-1.45 (m, 5H), 1.63-1.88 (m, 4H), 1.99-2.14 (m, 2H), 2.23-2.42 (m, 2H).

1. temperaturerefluxing
2. temperaturethe resulting solution refluxed for 1 hour
3. temperatureAfter cooling to room temperature
4. extractionThe mixture was extracted with ether
5. washthe combined organic extracts were washed with NaHCO3, H2O, brine
6. dry with materialdried over MgSO4
7. customPurification by column chromatography