反应详情

A solution of (S)-2-(3-Acetylamino-2-oxo-2H-pyridin-1-yl)-butyric acid tert-butyl ester (569 mg, 1.93 mmol) in dichloromethane (5 mL) was cooled to 0° C. Trifluoroacetic acid (5 ml) was added and the resulting mixture allowed to warm to room temperature and stir for 2 hours. The mixture was then concentrated under reduced pressure and the residue redissolved in dichloromethane. This process was repeated several times in order to remove excess trifluoroacetic acid. The resulting solid was slurried in diethyl ether, filtered and washed with more diethyl ether. The solid was then dried to constant weight under vacuum. This gave the title product as a white solid (327 mg, 71%); 1H NMR (400 MHz, d6-DMSO) δ 0.78 (3H, t), 2.02-2.17 (5H, m), 4.98 (1H, dd), 6.29 (1H, t), 7.35 (1H, d), 8.21 (1H, d), 9.30 (1H, s), 13.07 (1H, vbr s).

1. concentrationThe mixture was then concentrated under reduced pressure
2. dissolutionthe residue redissolved in dichloromethane
3. customto remove excess trifluoroacetic acid
4. filtrationfiltered
5. washwashed with more diethyl ether
6. customThe solid was then dried to constant weight under vacuum