反应详情

First 25.6 g (0.25 mol) of acetic anhydride and then 27.8 g (0.25 mol) of pivaloyl cyanide were introduced, in each case at room temperature, into 49.0 g (0.5 mol) of concentrated sulphuric acid, which had been initially introduced into the reaction vessel. After subsequently stirring this reaction mixture for 0.5 hour, it was stirred into a solution of 26.6 g (0.25 mol) of thiocarbohydrazide in 300 ml of 1 N HCl at 20°-30° C. When the addition had ended, the mixture was subsequently stirred at 50°-55° C. for a further 1.5 hours; after cooling, the reaction product which had precipitated was filtered off, washed with 200 ml of water and dried. 48.6 g (97% of theory) of 4-amino-6-tert.-butyl-3-mercapto-1,2,4-triazin-5(4H)-one (V) were obtained as colorless crystals of melting point 212°-214° C.; content according to a determination by gas chromatography >99 %. No further purification operations were necessary for subsequent reactions.

1. additionhad been initially introduced into the reaction vessel
2. additionWhen the addition
3. stirringthe mixture was subsequently stirred at 50°-55° C. for a further 1.5 hours
4. temperatureafter cooling
5. customthe reaction product which had precipitated
6. filtrationwas filtered off
7. washwashed with 200 ml of water
8. customdried