反应详情

A mixture of 69.7 g of product from Example 63, 29.55 g of potassium hydroxide, 45 of water and 800 ml ethyl alcohol is heated at reflux temperature for 89 hours. The cooled solution was made acidic (pH 2) with concentrated hydrogen chloride; followed by heating to distill off the ethyl alcohol. The solution is diluted with diethyl ether and water. The organic layer is dried and concentrated in vacuo. The residue is recrystallized from methylene chloride/hexane to give 40.0 g of the desired product as colorless needles.

1. temperatureis heated
2. temperatureat reflux temperature for 89 hours
3. temperatureby heating
4. distillationto distill off the ethyl alcohol
5. additionThe solution is diluted with diethyl ether and water
6. customThe organic layer is dried
7. concentrationconcentrated in vacuo
8. customThe residue is recrystallized from methylene chloride/hexane