反应详情

温度

12.5 °C

A suspension of (S)-3-(3′-chloro-biphenyl-4-yl)-2-((S)-1-ethoxycarbonyl-ethylamino)-propionic acid benzyl ester (10.0 g, 21.5 mmol) and 5% Pd on carbon (0.914 g) in EtOAc (200 mL) was treated with H2 (balloon) and stirred at 10-15° C. for 1.5 hour and at room temperature for 0.5 hour. The resulted precipitate was dissolved in methanol and filtered through celite pad. The filtrate was concentrated under reduced pressure and the obtained residue was re-crystallized from EtOAc to give (S)-3-(3′-chloro-biphenyl-4-yl)-2-((S)-1-ethoxycarbonyl-ethylamino)-propionic acid (5.6 g). The mother liquor was concentrated under reduced pressure and purified by silica gel column chromatography to give additional amount of (S)-3-(3′-chloro-biphenyl-4-yl)-2-((S)-1-ethoxycarbonyl-ethylamino)-propionic acid (1.4 g). 1H NMR (400 MHz, DMSO-d6) δ 1.13 (t, 3H, J=7.1 Hz), 1.15 (d, 3H, J=6.8 Hz), 2.85 (dd, 1H, J=7.1, 14.1 Hz), 2.93 (dd, 1H, J=6.3, 13.6 Hz), 3.30-3.37 (m, 1H), 3.48 (dd, 1H, J=6.5, 6.5 Hz), 4.03 (q, 2H, J=7.1 Hz), 7.32 (d, 2H, J=8.3 Hz), 7.38-7.43 (m, 1H), 7.48 (dd, 1H, J=7.8, 7.8 Hz), 7.59-7.65 (m, 3H), 7.70 (dd, 1H, J=2.0, 2.0 Hz); MS: m/z (MH+) 376.

1. additionwas treated with H2 (balloon)
2. filtrationfiltered through celite pad
3. concentrationThe filtrate was concentrated under reduced pressure
4. customthe obtained residue was re-crystallized from EtOAc