反应详情

To a solution of ethyl 5-(4-formyl-3,5-dimethoxyphenoxy)valerate (37 g, 119 mmol) in methanol (200 mL) was added 4 N sodium hydroxide (200 mL) and the mixture was stirred for 2 h. The methanol was removed in vacuo, water (100 mL) was added and the mixture was washed with ethyl acetate (100 mL) and dichloromethane (2×100 mL). The aqueous layer was acidified with 12 N hydrochloric acid until pH˜3 and extracted with ethyl acetate (2×200 mL). The combined organic layers were washed with brine (2×50 mL), dried (magnesium sulfate) and concentrated in vacuo. The obtained product was recrystallized from ethanol to give 26 g of 5-(4-formyl-3,5-dimethoxyphenoxy)valeric acid.

1. customThe methanol was removed in vacuo, water (100 mL)
2. additionwas added
3. washthe mixture was washed with ethyl acetate (100 mL) and dichloromethane (2×100 mL)
4. extractionextracted with ethyl acetate (2×200 mL)
5. washThe combined organic layers were washed with brine (2×50 mL)
6. dry with materialdried (magnesium sulfate)
7. concentrationconcentrated in vacuo
8. customThe obtained product was recrystallized from ethanol