反应详情

Nitromethane (2.54 ml, 46 mmol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (5.4 ml, 36 mmol) were added to a solution of methyl (E)-2-hexenoate (4.62 g, 36 mmol) in acetonitrile (20 ml) and the reaction mixture was stirred at room temperature for 14 hours. The reaction mixture was acidified by addition of a 1N HCl aqueous solution and then extracted with ethyl acetate. After washing the organic layer with brine and drying over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (solvent: n-hexane-ethyl acetate) to yield the title compound (3.64 g) as a light yellow oil. 1H-NMR (CDCl3) δ(ppm) 0.92 (3H, t, J=0.8 Hz), 1.29-1.48 (4H, m), 2.45 (2H, d, J=6.4 Hz), 2.57-2.68 (1H, m), 3.69 (3H, s), 4.43 (1H, dd, J=14.0 Hz, 6.0 Hz), 4.50 (1H, dd, J=14.0, 6.8 Hz)

1. extractionextracted with ethyl acetate
2. washAfter washing the organic layer with brine
3. dry with materialdrying over anhydrous magnesium sulfate
4. distillationthe solvent was distilled off under reduced pressure
5. customThe residue was purified by silica gel column chromatography (solvent: n-hexane-ethyl acetate)