反应详情

0.7 g (16.5 mmol) of sodium hydride are added portionwise to a solution at 0° C. of 3.9 g (16.5 mmol) of methyl (diethoxyphosphoryl)methoxyacetate in 45 mL of tetrahydrofuran. The reaction mixture is stirred for 45 minutes at room temperature, followed by dropwise addition of 3.4 g (11.8 mmol) of 3-butoxy-4-iodobenzaldehyde (prepared as described in Example 19g) in 30 mL of tetrahydrofuran. The reaction is slightly exothermic and the reaction mixture is maintained at a temperature of 25-27° C. with an ice bath. When the temperature has stabilized, the reaction mixture is stirred for 20 hours at room temperature. The reaction is worked up by addition of 60 mL of water and extraction with ethyl acetate. The organic phases are combined, washed with saturated sodium chloride solution and then dried over magnesium sulfate. The solvents are evaporated off. The crude product obtained is purified by chromatography on a column of silica eluted with a 98/2 heptane/ethyl acetate mixture. 1.5 g (33%) of the isomer methyl (Z)-3-(3-butoxy-4-iodophenyl)-2-methoxyacrylate are obtained in the form of a yellow solid and 1.0 g of the isomer (E)-3-(3-butoxy-4-iodophenyl)-2-methoxyacrylate are obtained in the form of a pale yellow oil.

1. temperaturethe reaction mixture is maintained at a temperature of 25-27° C. with an ice bath
2. stirringthe reaction mixture is stirred for 20 hours at room temperature
3. washwashed with saturated sodium chloride solution
4. dry with materialdried over magnesium sulfate
5. customThe solvents are evaporated off
6. customThe crude product obtained
7. customis purified by chromatography on a column of silica
8. washeluted with a 98/2 heptane/ethyl acetate mixture