[Cl:1][C:2]1[CH:3]=[C:4]([OH:11])[C:5]([N+:8]([O-:10])=[O:9])=[N:6][CH:7]=1.[H-].[Na+].Br[CH2:15][CH2:16][O:17][CH3:18].O>CN(C=O)C>[Cl:1][C:2]1[CH:3]=[C:4]([O:11][CH2:15][CH2:16][O:17][CH3:18])[C:5]([N+:8]([O-:10])=[O:9])=[N:6][CH:7]=1
5-Chloro-2-nitro-pyridine-3-ol (1.15 mmol) is dissolved in DMF (2 ml) and NaH (1.4 eq., 60% suspension in liquid paraffin) is added and the suspension is stirred 45 min at room temperature. 1-Bromo-2-methoxy-ethane (1 eq.) is added and the reaction suspension is heated to 100° C. for 24 hours. The reaction solution is pored into water and extracted with dichloromethane. The combined organic layers are washed with brine, dried over MgSO4 and the solvent is removed in vacuo. 5-Chloro-3-(2-methoxy-1-ethoxy)-2-nitro-pyridine is obtained after column chromatography as beige solid in a yield of 60%; mp. 71.5-72.5°; HPLC (method C): 1.63 min; LC-MS (method A): 1.36 min, 232.95 (M+H+).
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