반응 #1152285

반응 방정식

acetic anhydride

pivaloyl cyanide

sulphuric acid

thiocarbohydrazide

→

4-amino-6-tert.-butyl-3-mercapto-1,2,4-triazin-5(4H)-one

수율 97.1%

용매

HCl

반응 조건

후처리

1. 1
   workup.ADDITIONhad been initially introduced into the reaction vessel
2. 2
   workup.ADDITIONWhen the addition
3. 3
   workup.STIRRINGthe mixture was subsequently stirred at 50°-55° C. for a further 1.5 hours
4. 4
   온도after cooling
5. 5
   기타the reaction product which had precipitated
6. 6
   여과was filtered off
7. 7
   세척washed with 200 ml of water
8. 8
   기타dried

실험 절차

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.

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