反应详情

A solution of sodium hydroxide (2.15 g, 54 mmol) in water (15 ml) was added dropwise to a stirred solution of diethyl 1,1-cyclopropanedicarboxylate (10 g, 54 mmol) in ethanol (30 ml) while the temperature was maintained below 25° C. After the completion of the addition, the resulting mixture was stirred at room temperature for 60 hours. Most of ethanol was removed by evaporation in vacuo and the residue was diluted with brine, acidified with 6N hydrochloric acid and extracted with diethyl ether. The extract was dried over magnesium sulfate, filtered and concentrated. The residue was purified by distillation to give the title compound (bp 66°-9° C./0.15 mm) as a viscous oil.

1. temperaturewas maintained below 25° C
2. additionAfter the completion of the addition
3. customMost of ethanol was removed by evaporation in vacuo
4. additionthe residue was diluted with brine
5. extractionextracted with diethyl ether
6. dry with materialThe extract was dried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. distillationThe residue was purified by distillation