反应详情

Potassium methoxide (0.15 g, 2.04 mmol) in methanol (3 mL) was added dropwise to a stirring solution of 2 (0.49 g, 2.04 mmol) in methanol (5 mL) at 0° C. After 10 minutes, the mixture was partitioned between ether (100 mL) and water (50 mL). The ether layer was washed with brine, dried (MgSO4) and the solvent was evaporated under reduced pressure. The residue was chromatographed (SiO2, pentane/ether, 98:2) to give the nitro-alkene 3 (0.21 g, 57%) as a pale yellow oil; Rf (heptane/ethyl acetate, 8:2) 0.54; vmax(film)/cm−1 1643 (C═C), 1509 (NO2), 1342 (NO2); δH (400 MHz; CDCl3): 7.12 (1H, quint, J=2.0, CHNO2), 3.01 (1H, ddt, J=20.5, 8.0, 2.1), 2.90 (1H, ddt, J=20.5, 7.3, 2.1), 2.54 (1H, ddt, J=17.8, 7.1, 2.0), 2.43 (1H, ddt, J17.7, 5.6, 1.9), 2.21 (1H, m), 2.12 (1H, m), 1.60–1:24 (8H, m).

1. customthe mixture was partitioned between ether (100 mL) and water (50 mL)
2. washThe ether layer was washed with brine
3. dry with materialdried (MgSO4)
4. customthe solvent was evaporated under reduced pressure
5. customThe residue was chromatographed (SiO2, pentane/ether, 98:2)