[N+:1]([C:4]1[C:9]([O:10][CH3:11])=[CH:8][CH:7]=[CH:6][N:5]=1)([O-])=O.Cl[CH2:13][P:14](=[O:21])([O:18][CH2:19][CH3:20])[O:15][CH2:16][CH3:17].C(O[Na])(C)(C)C.Cl>CS(C)=O>[NH2:1][C:4]1[N:5]=[CH:6][C:7]([CH2:13][P:14](=[O:21])([O:18][CH2:19][CH3:20])[O:15][CH2:16][CH3:17])=[CH:8][C:9]=1[O:10][CH3:11]
A solution of 2-nitro-3-methoxypyridine (300 mg, 1.95 mmol) and diethyl chloromethylphosphonate (363 mg, 1.95 mmol) in DMSO (4 mL) was added dropwise to vigorously stirred solution of t-BuONa (0.561 g, 5.84 mmol) in DMSO (4 mL) at room temperature. The reaction mixture turned to deep orange immediately. Stirring was continued for 30 min, then the mixture was poured into 1 M HCl (aq) (10 mL). The product was extracted into ether (3×30 mL), dried over MgSO4, concentrated, and purified by silica gel chromatography (3% MeOH in DCM) to afford 102.6 mg of diethyl [(6-amino-5-methoxypyridin-3-yl)methyl]phosphonate (yield: 17%). 1H NMR (CD3OD, 400 MHz): δ=1.30 (t, J=6.8 Hz, 6 H), 3.45 (d, J=22.4 Hz, 2 H), 4.00 (s, 3 H), 4.09-4.17 (m, 4 H), 7.79 (t, J=2.4 Hz, 1 H), 7.97 (t, J=2.4 Hz, 1 H). MS (ES+): m/z 305.07 [MH+]. HPLC: tR=1.17 min (UPLC TOF, polar—3 min).
Wird geladen…
