反应详情

Fluoroacetyl chloride (7.1 g, 73 mmoles) was added dropwise to a stirred solution of 2,2-dimethyl-1,3-dioxane-4,6-dione (10.65 g, 74 mmoles) and pyridine (16.85 ml, 210 mmoles) in methylene chloride (75 ml) keeping the temperature below 10°. After stirring for 16 hours at room temperature the solution was diluted with methylene chloride (100 ml and then washed with 1N hydrochloric acid (200 ml) and water (100 ml). The organic extract was dried (Na2SO4) and the solvent removed in vacuo. The residue was dissolved in methanol (150 ml) and the solution heated at reflux for 2.5 hours. Removal of the solvent followed by distillation at 60°-80° (bath temp)/14 mm Hg gave methyl 4-fluoro-3-oxobutanoate (6.4 g).

1. customthe temperature below 10°
2. washwashed with 1N hydrochloric acid (200 ml) and water (100 ml)
3. extractionThe organic extract
4. dry with materialwas dried (Na2SO4)
5. customthe solvent removed in vacuo
6. dissolutionThe residue was dissolved in methanol (150 ml)
7. temperaturethe solution heated
8. temperatureat reflux for 2.5 hours
9. customRemoval of the solvent
10. distillationfollowed by distillation at 60°-80° (bath temp)/14 mm Hg