反应详情

Lithium hydroxide hydrate (77 mg; 1.85 mmole) in water (5.5 ml) was slowly added to a solution of 3-{4-[2-(4-tert-butoxycarbonylaminophenyl)ethoxy]phenyl}-2-ethoxypropanoic acid ethyl ester (described in Example 38) (0.77 g; 1.68 mmole) in tetrahydrofuran (7.6 ml). After stirring at room temperature for 4 hours the reaction mixture was kept in a freezer for 4 days. Tetrahydrofuran was removed by evaporation in vacuo. More water was added and the mixture was acidified with hydrochloric acid to pH1. The product was extracted with ethyl acetate, washed twice with water, dried (sodium sulfate), filtered and the solvent was evaporated in vacuo to give 0.712 g (98.7% yield) of 3-{4-[2-(4-tert-butoxycarbonylaminophenyl)ethoxy]phenyl}-2-ethoxypropanoic acid.

1. waitwas kept in a freezer for 4 days
2. customTetrahydrofuran was removed by evaporation in vacuo
3. additionMore water was added
4. extractionThe product was extracted with ethyl acetate
5. washwashed twice with water
6. dry with materialdried (sodium sulfate)
7. filtrationfiltered
8. customthe solvent was evaporated in vacuo