反应详情

Crude methyl 1-(4-(5-bromopyrimidin-2-ylamino)phenethyl)piperidine-4-carboxylate 20 is suspended in THF/MeOH/H2O (3:2:1, 10 mL) and 6N LiOH (9.3 mmol) and stirred at rt for 2 h. After neutralization to pH 6 by addition of HCl (1N), the solvent is removed under vacuum to give a solid which is dissolved in THF (20 mL). To the above suspension, excess Na2SO4 is added and filtered. The filtrate is concentrated to yield 1-(4-(5-bromopyrimidin-2-ylamino)phenethyl)piperidine-4-carboxylic acid 21. 1H NMR (400 MHz, d6-DMSO) δ 9.87 (s, 1H), 9.39 (bs, 1H), 8.59 (s, 2H), 7.66 (d, J=8.4 Hz, 2H), 7.20 (d, J=8.4 Hz, 2H), 3.58-3.64 (m, 2H), 3.48-3.28 (m, 1H), 3.22-3.27 (m, 2H), 2.88-3.03 (m, 4H), 2.05-2.15 (m, 2H), 1.66-1.80 (m, 2H). MS (m/z) (M+1)+: 405.1, 407.1.

1. customthe solvent is removed under vacuum
2. customto give a solid which
3. filtrationfiltered
4. concentrationThe filtrate is concentrated