反应详情

Sodium hydride (ca. 60%, 1.0 g, 28.1 mmol) was suspended in tetrahydrofuran (12 ml), and a solution of diethyl cyanoethylphosphonate (4.7 g, 26.8 mmol) in tetrahydrofuran (12 ml) was added thereto under ice cooling condition. The reaction mixture was stirred for 1 hr. A solution of 2-pyridinecarbaldehyde (2.7 g, 25.0 mmol) in tetrahydrofuran (10 ml) was added to the mixture, and the mixture was stirred at 0° C. to room temperature for 6 hrs. The reaction mixture was combined with water under ice cooling condition, concentrated to the half amount and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over magnesium sulfate. The solvent was evaporated, and the residue was subjected to a silica gel (100 g) column chromatography. The fractions eluted with hexane-ethyl acetate (2:1, v/v) were collected and concentrated to give Z-form of the titled compound (0.50 g, 15%). And simultaneously, the fractions eluted with hexane-ethyl acetate (3:2, v/v) were collected and concentrated to give E-form of the titled compound.

1. stirringthe mixture was stirred at 0° C. to room temperature for 6 hrs
2. concentrationconcentrated to the half amount
3. extractionextracted with ethyl acetate
4. washThe organic layer was washed with saturated brine
5. dry with materialdried over magnesium sulfate
6. customThe solvent was evaporated
7. washThe fractions eluted with hexane-ethyl acetate (2:1, v/v)
8. customwere collected
9. concentrationconcentrated