Hydrogen Bromide → HCID 178419310, compound

Temperature

0 °C

20 g of 3-amino-5-phenylpyrazole were suspended in 200 ml of a 24% aqueous hydrogen bromide solution and a solution of 9.5 g of sodium nitrite in 20 ml of water was added dropwise at 0° C. in the course of 10 min. The mixture was stirred at 0° C. for 10 min. Then the obtained suspension was added in portions to a suspension of 19.8 g of copper(I) bromide in 100 ml of a 24% aqueous hydrogen bromide solution. Subsequently, the mixture was stirred at room temperature for 2 h and then extracted three times with 300 ml each of EA. The combined organic phases were washed twice with 100 ml each of water and once with 100 ml of a saturated aqueous sodium carbonate solution. The organic phase was dried over magnesium sulfate and the solvent was removed in vacuo. Chromatography on silica gel with EA/HEP (1:5) yielded 5.7 g of the title compound as a colorless oil.

1. stirringSubsequently, the mixture was stirred at room temperature for 2 h
2. extractionextracted three times with 300 ml each of EA
3. washThe combined organic phases were washed twice with 100 ml each of water and once with 100 ml of a saturated aqueous sodium carbonate solution
4. dry with materialThe organic phase was dried over magnesium sulfate
5. customthe solvent was removed in vacuo

ORD record

ord-07fc6daeb124402e89e9250664833ba4

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08076324B2