反应详情

85.3 g of 2-ethoxycarbonyl-2,5-dimethyl-4-hexenoic acid ethyl ester was dissolved in 645 ml of dimethyl sulfoxide and combined in succession with 29.7 g of lithium chloride and 6.3 ml of distilled water. The reaction mixture was thereafter heated a total of 13 hours to 200° C. and subsequently--after cooling--poured on 1 liter of ice water. The aqueous phase was extracted three times with respectively 500 ml of methylene chloride. The combined organic extracts then were washed twice with water, dried over magnesium sulfate, concentrated on a forced circulation evaporator, and distilled under vacuum, thus isolating 53.1 g, bp13 75°-78° C.

1. temperatureThe reaction mixture was thereafter heated a total of 13 hours to 200° C.
2. temperaturesubsequently--after cooling
3. extractionThe aqueous phase was extracted three times with respectively 500 ml of methylene chloride
4. washThe combined organic extracts then were washed twice with water
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated on a forced circulation evaporator
7. distillationdistilled under vacuum
8. customthus isolating 53.1 g, bp13 75°-78° C.