反应详情

温度

-78 °C

n-Butyl lithium (2.18 M, 24 mL, 52.51 mmol) is added slowly to a solution of 4-(N-t-butoxycarbonylamino)-pyridine (4.08 g, 21 mmol) in THF (50 mL, stirred under N2 at −78° C. The solution is allowed to warm to 0° C., stirred for 3 h, then cooled again to −78° C. and poured into ether (100 mL) containing dry ice. The solution is warmed to room temperature with constant stirring. Water is added and the mixture is neutralized with acetic acid. The resulting solid is collected by vacuum filtration and dried in a vacuum oven to give 4-(N-t-butoxycarbonylamino)nicotinic acid (2.72 g, 54%) as a brown solid. 1H NMR (DMSO) δ 11.75 (1H, brs), 8.95 (1H, s), 8.50 (1H, d, J=6.0 Hz) 8.20 (1H, d, J=6.0 Hz), 1.49 (9H, s).

1. temperatureto warm to 0° C.
2. stirringstirred for 3 h
3. temperaturecooled again to −78° C.
4. temperatureThe solution is warmed to room temperature with constant stirring
5. filtrationThe resulting solid is collected by vacuum filtration
6. customdried in a vacuum oven