反应详情

温度

80 °C

To a slurry of 212.0 g of 2,4-dinitrobenzoic acid in 1400 ml of toluene was added with agitation 101.0 g of triethylamine, followed by 122.7 g of N-methylpiperazine. Next 75.7 g of phosphorus oxychloride was added dropwise at such a rate to maintain the reaction temperature below 90° C. The mixture was refluxed for 5 hrs, cooled to 80° C., and poured slowly into 1000 ml of aqueous 5% NaHCO3 solution with stirring. The precipitate was filtered, washed with water and recrystallized from hot methanol to yield 161 g of N1 -methyl-N4 -(2,4-dinitrobenzoyl)piperazine, mp 130°-132° C.

1. temperatureto maintain the reaction temperature below 90° C
2. temperatureThe mixture was refluxed for 5 hrs
3. filtrationThe precipitate was filtered
4. washwashed with water
5. customrecrystallized from hot methanol