反应详情

A mixture of 25.6 g (0.0705 mol) of product of Example 5, 20 g of KOH and 250 ml of methanol was held at reflux for 16 hours. The reaction mixture was concentrated under reduced pressure to give a solid. This solid was dissolved in water (250 ml) and extracted with ether. Three layers were separated. The top layer (ether) was discarded. The bottom two layers were acidified with 100 ml of concentrated HCl. The organic layer was separated and extracted into ether. The ether extracts were dried and concentrated to give 21.2 g (89%) of solid which was crystallized from hexane at low temperature to give 5.1 g of pure product: mp 90°-93.5° C. and 5.1 g of second crop, mp 89°-92.5° C.

1. temperatureat reflux for 16 hours
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. customto give a solid
4. extractionextracted with ether
5. customThree layers were separated
6. customThe organic layer was separated
7. extractionextracted into ether
8. dry with materialThe ether extracts were dried
9. concentrationconcentrated