[C:1]([C:3]1[C:8]([N+:9]([O-])=O)=[CH:7][C:6]([CH3:12])=[CH:5][N:4]=1)#[N:2].C([O-])(O)=O.[Na+].O>C(O)(=O)C.CCOC(C)=O.[Fe]>[NH2:9][C:8]1[C:3]([C:1]#[N:2])=[N:4][CH:5]=[C:6]([CH3:12])[CH:7]=1To acetic acid (300 mL) in a 3-neck 2 liter round bottom flask equipped with mechanical stirrer and a thermometer was added Fe powder (99.6 g, 1.78 mol) with stirring at 60° C. 2-Cyano-5-methyl-3-nitropyridine (97 g, 0.59 mol) was dissolved in acetic acid (400 mL) with gentle warming and added to the above reaction mixture drop wise with efficient stirring so that the reaction temperature kept below 80° C. over 3.5 hours. The reaction mixture was further stirred for an addition 30 min, cooled, diluted with EtOAc (750 mL), filtered through celite and washed with EtOAc (1×500 mL, 3×250 mL). Combined EtOAc layers were evaporated to dryness to obtain dark brown solid which was neutralized with saturated NaHCO3 solution (850 mL), after addition of water (250 mL) to obtain homogeneous, this aqueous layer was extracted with EtOAc (1×750 mL, 2×500 mL). Combined EtOAc layers were filtered through small pad of silica gel (sand-SiO2-sand in sintered funnel), dried (Na2SO4) and evaporated to obtain 3-amino-2-cyano-5-methylpyridine (60 g) as yellow solid in 76% yield including ˜10% corresponding amide.
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