Nitric Acid → 5-Chloro-3-methyl-4-nitro-1-phenyl-1H-pyrazole

Reaction equation

[Cl:1][C:2]1[N:6]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=2)[N:5]=[C:4]([CH3:13])[CH:3]=1.[N+:14]([O-])([O:16]C(=O)C)=[O:15].[N+]([O-])(O)=O>C(OC(=O)C)(=O)C>[Cl:1][C:2]1[N:6]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=2)[N:5]=[C:4]([CH3:13])[C:3]=1[N+:14]([O-:16])=[O:15]

Participants

Procedure

A solution of 9.6 g (0.05 mole) of 5-chloro-3-methyl-1-phenylpyrazole and 25 ml of acetic anhydride was added at 10° C. to a solution of acetyl nitrate prepared from 25 ml of 90% nitric acid and 10 ml of acetic anhydride. The solution was stirred 2 hours at 20°-30° C. and carefully poured onto ice water. The solid was filtered off and washed with cold water. One recrystallization from ethanol gave long white needles of product.