[CH2:1]([O:3][C:4]1[C:9]([C:10]([F:13])([F:12])[F:11])=[CH:8][C:7]([N+:14]([O-])=O)=[CH:6][N:5]=1)[CH3:2].O.O.[Sn](Cl)Cl.C([O-])(O)=O.[Na+]>CC(=O)OCC>[CH2:1]([O:3][C:4]1[N:5]=[CH:6][C:7]([NH2:14])=[CH:8][C:9]=1[C:10]([F:13])([F:11])[F:12])[CH3:2]To a mixture of 2-ethoxy-5-nitro-3-(trifluoromethyl)pyridine (120 mg, 0.508 mmol) in EA (10 mL) was added tin(II) chloride dihydrate (459 mg, 2.033 mmol). The mixture was stirred at 50° C. for 16 h. Then the solution was distributed between EA and saturated NaHCO3 solution. The combined organic extract was washed with brine, dried over MgSO4, filtered and concentrated. The crude material was purified by preparative TLC (PE/EA=4:1, Rf=0.6) to yield a light yellow oil of 6-ethoxy-5-(trifluoromethyl)pyridin-3-amine (80 mg, 0.310 mmol, 61.1% yield): 1H NMR (400 MHz, CD3OD) δ 6.27 (d, J=2.5 Hz, 1H), 5.86 (d, J=3.0 Hz, 1H), 2.81 (m, 2H), 0.17 (t, J=7.0 Hz, 3H); ES-LCMS m/z 207.1 (M+H).
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