反应详情

To a stirring suspension of the triethyl phosphonoacetate (1.695 mL, 8.54 mmol) in 10 mL THF at 0° C. was added 1 M potassium tert-butoxide in THF (8.54 mL, 8.54 mmol). The resulting reddish orange solution was stirred for 30 min and then treated with a solution of the 2-(4-chlorophenyl)-2-methylpropanal (Intermediate I-9A, 0.78 g, 4.27 mmol) in 2.5 mL of THF and slowly warmed to room temperature. The reaction mixture was stirred at room temperature for 3 hrs and quenched with saturated. aq. ammonium chloride. The reaction mixture was partitioned between ethyl acetate and water. The organic layer was then washed with brine, dried over anhyd. magnesium sulfate, concentrated and chromatographed using silica gel flash chromatography to yield ethyl 4-(4-chlorophenyl)-4-methylpent-2-enoate (0.48 g, 1.899 mmol, 44.5% yield) as a clear oil. 1H NMR (400 MHz, CDCl3) δ ppm 7.28 (2H, d, J=8.79 Hz), 7.22 (2H, d, J=8.79 Hz), 7.08 (1H, d, J=16.26 Hz), 5.79 (1H, d, J=15.82 Hz), 4.20 (2H, q, J=7.03 Hz), 1.29 (3H, t, J=7.25 Hz).

1. stirringThe reaction mixture was stirred at room temperature for 3 hrs
2. customquenched with saturated
3. customThe reaction mixture was partitioned between ethyl acetate and water
4. washThe organic layer was then washed with brine
5. customdried over anhyd
6. concentrationmagnesium sulfate, concentrated
7. customchromatographed