Lithium hydroxide, monohydrate → (S)-2-[4-(3-cyclopropyl-2-fluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-pentanoic acid

Beteiligte Stoffe

Reaktionsschritte

To a solution containing (S)-2-[4-(3-cyclopropyl-2-fluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-pentanoic acid ethyl ester (0.800 g, 0.002 mol) in tetrahydrofuran (30 mL) was treated with an aqueous solution of lithium hydroxide monohydrate (0.5N, 15 mL, 0.008 mol). The mixture was stirred at room temperature for 1 h, and the solvents evaporated. The residue was dissolved in water and washed with diethyl ether, and the diethyl ether layer discarded. The aqueous phase was acidified with dilute hydrochloric acid (pH <2), and extracted with ethyl acetate. The combined organic layers were dried over sodium sulfate and concentrated to afford (S)-2-[4-(3-cyclopropyl-2-fluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-pentanoic acid (0.71 g, 96%) as a yellow solid.

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