反应详情

139 g. of 4,6-dichloro-2-methyl-5-nitropyridine-3-carboxylic acid, ethyl ester (0.5 Mol.) are dissolved in about 500 ml. of methanol. 60 g. of triethylamine are added and the solution is heated at reflux temperature. At this point, 50.1 g. of [3-(dimethylamino)propyl]amine are added dropwise. After the addition is completed, heating is continued for 10 minutes. The solvent is removed in vacuo and the residue is suspended with 200 ml. of water. The aqueous mixture is made alkaline with 10% sodium hydroxide solution and extracted three times with 200 ml. portions of ethyl acetate. The organic layer is dried over calcium chloride, evaporated to dryness and crystallized with petroleum ether to obtain 4-[[3-(dimethylamino)propyl]amino]-6-chloro-2-methyl-5-nitropyridine-3-carboxylic acid, ethyl ester, yield 102 g. (59%), m.p. 20°.

1. temperaturethe solution is heated
2. temperatureat reflux temperature
3. additionAfter the addition
4. temperatureheating
5. customThe solvent is removed in vacuo
6. extractionextracted three times with 200 ml
7. dry with materialThe organic layer is dried over calcium chloride
8. customevaporated to dryness
9. customcrystallized with petroleum ether