反应详情

To a solution of (S)-2-[4-(2,6-difluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-pentanoic acid methyl ester (0.108 g, 0.33 mol) in tetrahydrofuran:water (1:1, 8 mL) was added lithium hydroxide monohydrate (0.042 g 1.00 mmol). The mixture was stirred at room temperature for 2 h. The reaction mixture was poured into water and washed with diethyl ether and the diethyl ether layer discarded. The aqueous phase was acidified with 1N aqueous hydrochloric acid (pH <2), and extracted with ethyl acetate (2×30 mL). The combined ethyl acetate layers were dried over magnesium sulfate, filtered and concentrated to afford (S)-2-[4-(2,6-difluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-pentanoic acid, (0.086 g, 87%), as an off-white solid: LR-ES-MS m/z calculated for C15H15F2NO4 [M+H]+ 312, observed 312.

1. washwashed with diethyl ether
2. extractionextracted with ethyl acetate (2×30 mL)
3. dry with materialThe combined ethyl acetate layers were dried over magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated