Bromide ion → 3-Hexyl-2-cyclohexenone

참여 물질

반응 단계

To a solution of 3-ethoxy-2-cyclohexenone (8.62 g, 61.50 mmol) in dry THF (tetrahydrofuran), hexylmagnesuim bromide (15.38 mL, 2.0 M, 30.75 mmol) was added dropwise with stirring. The mixture was kept at 0° C. (in an ice-water bath) during the whole process and then was allowed to warm (the ice-water bath was removed) to ambient temperature (approximately 22° C.). Hydrochloric acid (10 mL, 3.0 M) was added to the above mixture. The mixture was extracted with diethylether 3 times. The combined organic layerswere washed with water and then dried over magnesium sulfate. The product was further purified by flash chromatography on silica gel using 10:100 (dicholomethane:hexane (volume:volume)) to yield 6.17 g (xx %) of 3-hexyl-2-cyclohexenone. 1H NMR (300 MHz, CDCl3): δ 5.78 (s, 1 H), 2.40-2.20 (m,4 H), 2.20-2.10 (t, J=7.37 Hz, 2H), 1.90 (p, J=6.50 Hz, 2 H), 1.42 (t, J=7.30 Hz, 2 H), 1.22 (br, 6 H), 0.81 (t, J=6.70 Hz, 3 H). 13C NMR (75 MHz, CDCl3): 200.06, 167.00, 126.04, 38.49, 37.80, 32.02, 30.11, 29.35, 27.35, 23.21, 22.95, 14.42, GC/MS calculated for C12H20O 180.15, found 180.15. The foregoing gas chromatography/mass spectrometry measurements confirmed the structure. Preparing the Compound of Formula II

출처 및 근거