[NH2:1][C:2]1[CH:7]=[C:6]([OH:8])[CH:5]=[CH:4][N:3]=1.C1CCN2C(=NCCC2)CC1.F[C:21]1[CH:26]=[CH:25][C:24]([N+:27]([O-:29])=[O:28])=[CH:23][C:22]=1[O:30][CH3:31].O>CC#N.CN(C=O)C>[CH3:31][O:30][C:22]1[CH:23]=[C:24]([N+:27]([O-:29])=[O:28])[CH:25]=[CH:26][C:21]=1[O:8][C:6]1[CH:5]=[CH:4][N:3]=[C:2]([NH2:1])[CH:7]=1To a suspension of 2-aminopyridin-4-ol (0.251 g, 2.28 mmol) in MeCN (4.0 mL) at RT was added DBU (423 μl, 2.80 mmol) and after 30 min a solution of 1-fluoro-2-methoxy-4-nitrobenzene (300 mg, 1.75 mmol) in DMF (2.0 mL) was added dropwise. The reaction mixture was maintained at RT for 1 hr and was then heated to 80° C. for 16 hr. After cooling to RT water (2.0 mL) was added and the mixture was evaporated in vacuo. The residue was partitioned between DCM (30 mL) and brine (20 mL) and the organic layer was separated and dried (MgSO4) and was evaporated in vacuo. The residue was purified by flash column chromatography (SiO2, 40 g, EtOAc in isohexane, 20-100%, gradient elution) to afford 4-(2-methoxy-4-nitrophenoxy)pyridin-2-amine as a bright yellow solid (234 mg, 50%); Rt 1.25 min (Method 2); m/z 262 (M+H)+ (ES+).
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