反应详情

To a stirred solution of sodium methoxide (24.3 g, 0.45 mole) in ethanol (700 ml) and ethyl acetoacetate (58.6 g, 0.45 mole) was added [2,3-dichloro-4-(2-methylene-1-oxobutyl)phenoxy]acetic acid (60.6 g, 0.20 mole). The reaction mixture was heated at reflux for 21/2 hours, then the solvent was distilled at reduced pressure. The residue was dissolved in water, acidified with hydrochloric acid, extracted into ether, washed with water, extracted into sodium bicarbonate, acidified, extracted into ether, dried over magnesium sulfate, filtered and evaporated in vacuo to give 68 g of [2,3-dichloro-4-(6-ethyl-3-oxo-1-cyclohexen-1-yl)phenoxy]acetic acid which melts at 170°-172° after recrystallization from nitromethane.

1. temperatureThe reaction mixture was heated
2. temperatureat reflux for 21/2 hours
3. distillationthe solvent was distilled at reduced pressure
4. dissolutionThe residue was dissolved in water
5. extractionextracted into ether
6. washwashed with water
7. extractionextracted into sodium bicarbonate
8. extractionextracted into ether
9. dry with materialdried over magnesium sulfate
10. filtrationfiltered
11. customevaporated in vacuo