反应详情

Diethyl [(5-methoxy-6-nitropyridin-3-yl)methyl]phosphonate (Compound 308B, 102.6 mg) was hydrogenated in the presence of 10% Pd/C (20 mg) in MeOH (5 mL) under 1 atmosphere for 4 h. The catalyst was filtered off, the filtrate was concentrated, and the residue (85 mg, 92% yield) was used in the next step without purification. 1H NMR (CDCl3, 400 MHz): δ=1.27 (dt, J=2.0, 6.8 Hz, 6 H), 3.02 (d, J=20.8 Hz, 2 H), 3.84 (s, 3 H), 4.01-4.08 (m, 4 H), 4.74 (s, 2H), 6.98 (t, J=2.0 Hz, 1 H), 7.52 (t, J=2.0 Hz, 1 H). MS (ES+): m/z 275.10 [MH+]. HPLC: tR=0.77 min (UPLC TOF, polar—3 min).

1. filtrationThe catalyst was filtered off
2. concentrationthe filtrate was concentrated