[CH2:1]([O:3][C:4]([C:6]1[C:7]([CH3:17])=[N:8][C:9]([Cl:16])=[C:10]([N+:13]([O-:15])=[O:14])[C:11]=1Cl)=[O:5])[CH3:2].[C:18]([NH2:22])([CH3:21])([CH3:20])[CH3:19]>C(N(CC)CC)C>[CH2:1]([O:3][C:4]([C:6]1[C:7]([CH3:17])=[N:8][C:9]([Cl:16])=[C:10]([N+:13]([O-:15])=[O:14])[C:11]=1[NH:22][C:18]([CH3:21])([CH3:20])[CH3:19])=[O:5])[CH3:2]55.8 g. of 4,6-dichloro-2-methyl-5-nitropyridine-3-carboxylic acid ethyl ester (0.2 mol.) are dissolved in 300 ml. of alcohol and 25 g. of triethylamine. At reflux temperature, 14.6 g. of tert. butylamine are slowly added dropwise and the mixture is heated with stirring for an additional 30 minutes. The solvent is distilled off in vacuo and the residue is dissolved in benzene. The precipitated triethylamine hydrochloride is filtered off and the benzene layer is evaporated to dryness. The remaining oil, 6-chloro-4-[(1,1-dimethylethyl)amino]-2-methyl-5-nitropyridine-3-carboxylic acid ethyl ester crystallizes with methanol, yield 38.4 g. (61%), m.p. 40°-43°.
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