Nitric Acid → 5,6-Dichloro-3-nitropyrazin-2-amine
Reaktionsgleichung
S(=O)(=O)(O)O.[NH2:6][C:7]1[C:8](C(O)=O)=[N:9][C:10]([Cl:14])=[C:11]([Cl:13])[N:12]=1.[N+:18]([O-])([OH:20])=[O:19]>>[Cl:14][C:10]1[N:9]=[C:8]([N+:18]([O-:20])=[O:19])[C:7]([NH2:6])=[N:12][C:11]=1[Cl:13]Komponenten
4
Versuchsvorschrift
To a 450 ml concentrated sulfuric acid cooled to 10 is added 50.0 g (0.2 m) 3-amino-5,6-dichloropyrazine carboxylic acid. To this solution cooled to 0°-5°, is added a cold solution of 15 ml fuming sulfuric acid in 15 ml fuming nitric acid dropwise over 15 minutes. The reaction mixture is stirred at 0°-5° for 2 hours and then at ambient temperature for 2 hours. The reaction mixture is the poured onto ice and the yellow solid is collected. This solid is taken up in ethyl acetate, and then washed twice with saturated sodium carbonate solution and then the solution is filtered through a pad of silica gel. The resulting solution is evaporated in vacuo to afford 35 g of 5,6-dichloro-3-nitropyrazinamine, m.p. 169°-170°.