反应详情

温度

70 °C

To a suspension obtained by adding a solution of 4-acetylbenzoic acid tert-butyl ester (7.82 g) in benzene-ether-tetrahydrofuran (3:3:2, 80 ml) to 4.64 g (71 mmol) of zinc, were added gradually under heating and stirring 4-bromocrotonic acid methyl ester (6.36 g) and iodine (20 mg). After reflux under heating in an oil bath at 70° C. for 1 hour, methyl 4-bromocrotonate (2.13 g) and zinc (1.55 g) were added, followed by reflux under heating for 30 minutes. The temperature was cooled down to room temperature, and the reaction mixture was poured into water (300 ml) and adjusted to pH 5 with acetic acid. The organic layer obtained by extraction with ether was washed with 5% aqueous ammonia and then dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the resulting residue was purified by column chromatography (support; silica gel, 200 g, developing agent; ethyl acetate:hexane=1:4), to obtain the object compound (9.2 g).

1. customTo a suspension obtained
2. additionwere added gradually
3. temperatureunder heating
4. temperatureAfter reflux
5. temperatureby reflux
6. temperatureunder heating for 30 minutes
7. temperatureThe temperature was cooled down to room temperature
8. washwas washed with 5% aqueous ammonia
9. dry with materialdried over anhydrous magnesium sulfate
10. customThe solvent was evaporated under reduced pressure
11. customthe resulting residue was purified by column chromatography (support; silica gel, 200 g, developing agent; ethyl acetate:hexane=1:4)