反应详情

To a solution of methyl (2S)-{[(2S)-2-hydroxy-4-methylpentanoyl]amino}(phenyl)acetate (76a) (4.185 g) in THF (30 ml) and water (15 ml) cooled to 0° C. was added lithium hydroxide (1.45 g) portion wise. The mixture was stirred at RT overnight. The reaction was acidified with 1N hydrochloric acid until pH=1. The mixture was concentrated to remove THF and extracted with Ethyl acetate (3×). The organic layers were washed with water, brine, dried, filtered and evaporated to afford the title compound as a tacky white solid. Trituration with dichloromethane/diethyl ether yielded a free flowing solid (3.85 g). 1H NMR (300 MHz, CDCl3) δ 0.89-0.94 (m, 6H), 1.45-1.63 (m, 2H), 1.76-1.83 (m, 1H), 3.25 (bs, 2H), 4.20-4.25 (m, 1H), 5.56 (d, 1H, J=7 Hz), 7.35-7.39 (m, 5H), 7.53 (d, 1H, J=7 Hz). MS APCI, m/z=266 (M+1). LC/MS: 1.68 min.

1. concentrationThe mixture was concentrated
2. customto remove THF
3. extractionextracted with Ethyl acetate (3×)
4. washThe organic layers were washed with water, brine
5. customdried
6. filtrationfiltered
7. customevaporated