反应详情

0.30 g (7.5 mmol) of sodium hydride is added portionwise to a solution at 0° C. of 1.80 g (7.5 mmol) of methyl (diethoxyphosphanyloxy)methoxyacetate (prepared according to Example 24b) in 20 mL of tetrahydrofuran. The reaction mixture is stirred for 45 minutes at room temperature and then 2 g (6.25 mmol) of 3-(2-ethoxyethoxy)-4-iodobenzaldehyde (prepared according to Example 38c) in 10 mL of tetrahydrofuran. The reaction is slightly exothermic, and the reaction mixture is maintained at a temperature of 25-30° C. with an ice-water bath. When the temperature has stabilized, the reaction mixture is stirred for 24 hours at room temperature. After addition of 50 mL of water and extraction with ethyl acetate, the organic phases are combined, washed with saturated sodium chloride solution, dried over sodium sulfate and evaporated. The crude product obtained is purified by chromatography on a column of silica eluted with a 95/5 heptane/ethyl acetate mixture to give 411 mg of methyl (Z)-3-[3-(2-ethoxyethoxy)-4-iodophenyl]-2-methoxyacrylate and 526 mg of methyl (E)-3-[3-(2-ethoxyethoxy)-4-iodophenyl]-2-methoxyacrylate in the form of colorless oils.

1. temperaturethe reaction mixture is maintained at a temperature of 25-30° C. with an ice-water bath
2. stirringthe reaction mixture is stirred for 24 hours at room temperature
3. washwashed with saturated sodium chloride solution
4. dry with materialdried over sodium sulfate
5. customevaporated
6. customThe crude product obtained
7. customis purified by chromatography on a column of silica
8. washeluted with a 95/5 heptane/ethyl acetate mixture