Ammonia → 5-Amino-4-nitroso-1-phenylpyrazole

Participants

Reaction Conditions

Reaction Steps

To a flask having an inner volume of 25 ml and equipped with a stirring device, a thermometer and a reflux condenser were charged, 2.97 g (20 mmol) of 3,3-dimethoxy-2-hydroxyiminopropionitrile with a purity of 96.9% by weight synthesized in the same manner as in Example 1, 2.32 g (21 mmol) of phenylhydrazine with a purity of 98% by weight, 10 ml of methanol and 3.0 ml (36 mmol) of conc. hydrochloric acid, and the mixture was reacted at 50 to 52° C. for one hour. After completion of the reaction, 10 ml of water was added to the mixture to cool the same up to 10° C., then, 2.3 ml (37.9 mmol) of 28% by weight aqueous ammonia was gradually added dropwise to the mixture, and the resulting mixture was stirred for 30 minutes while maintaining the liquid temperature to 5° C. or lower for 30 minutes. Precipitated crystals were collected by filtration, and the crystals were washed with 5 ml of cold water and dried under reduced pressure to obtain 3.19 g of 5-amino-4-nitroso-1-phenylpyrazole (Isolation yield: 63.4%) as an ocherous solid with a purity of 74.9% by weight (absolute calibration curve method by high performance liquid chromatography).

Provenance & Evidence