反应详情

To a solution of 3-methylthio-6-(p-fluorophenyl)-5-oxo-2,5-dihydro-1,2,4-triazine (2.5 g) in anhydrous dimethylformamide (50 ml), sodium hydride (50% dispersion, 0.5 g) was gradually added and stirred until the generation of hydrogen gas was not detected. o-Mesitylenesulfonylhydroxylamine (2.1 g) was added to the mixture, followed by stirring at room temperature for 6 hours. After completion of the reaction, the resultant mixture was poured into ice-water. The precipitated crystals were collected by filtration. Recrystallization of the obtained crystals from methanol gave 2.0 g of 2-amino-3-methylthio-6-(p-fluorophenyl)-5-oxo-2,5-dihydro-1,2,4-triazine in 74% yield. M.P., 192° C.

1. customAfter completion of the reaction
2. filtrationThe precipitated crystals were collected by filtration
3. customRecrystallization of the obtained crystals from methanol