反应详情

205 g. of 4,6-dichloro-3-pyridinecarboxylic acid, methyl ester (1 mol.) are dissolved in 1 liter of methanol. The solution is cooled to 0° and 100 g. of hydrazine hydrate are dropped in with stirring. The solution is kept at 0° for 12 hours. The precipitated 6-chloro-4-hydrazino-3-pyridinecarboxylic acid, methyl ester is filtered off and recrystallized from methanol, yield: 175 g. (87%); m.p. 163.3°.

1. temperatureThe solution is cooled to 0°
2. filtrationThe precipitated 6-chloro-4-hydrazino-3-pyridinecarboxylic acid, methyl ester is filtered off
3. customrecrystallized from methanol, yield: 175 g