Ammonia → HCID 11149124, compound

Temperature

10 °C

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, 3.43 g (21 mmol) of benzylhydrazine hydrochloride with a purity of 97% by weight, 1.4 ml of water, 6 ml of methanol and 1.3 ml (15 mmol) of conc. hydrochloric acid, and the mixture was reacted at 50 to 52° C. for 3 hours. After completion of the reaction, 5 ml of water was added to the mixture to cool the mixture 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. Precipitated crystals were collected by filtration, and then, the crystals were washed with 5 ml of cold water and dried under reduced pressure to obtain 3.89 g of 5-amino-1-benzyl-4-nitrosopyrazole (Isolation yield: 82.8%) as brown solid with a purity of 86.1% by weight (absolute calibration curve method by high performance liquid chromatography).

1. customTo a flask having
2. customan inner volume of 25 ml and equipped with a stirring device
3. additiona thermometer and a reflux condenser were charged
4. customthe mixture was reacted at 50 to 52° C. for 3 hours
5. additionwas added to the mixture
6. temperaturewhile maintaining the liquid temperature to 5° C.
7. customPrecipitated crystals
8. filtrationwere collected by filtration
9. washthe crystals were washed with 5 ml of cold water
10. customdried under reduced pressure

ORD record

ord-4f548fcbd914437c81438c5f71868c5c

Source dataset

uspto-grants-2007_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07227032B2