Potassium Iodide → HCID 178469927, compound

Ethyl 3-amino-1H-pyrazole-4-carboxylate (860.0 mg, 5.54 mmol) was dissolved in acetic acid (5 mL) and water (5 mL). Potassium iodide (921 mg, 5.54 mmol) was added and the mixture was stirred until all solids had dissolved. A solution of sodium nitrite (386 mg, 5.54 mmol) in water (2 mL) was then added dropwise. The reaction was stirred at room temperature for 2 minutes when stirring became hindered due to precipitate formation. Additional water (5 mL) was added and the reaction was allowed to stir overnight. The acetic acid was removed under reduced pressure. The brown residue was taken up in saturated aqueous sodium bicarbonate and was extracted with ethyl acetate (2×50 mL). The combined organics were washed with saturated aqueous sodium thiosulfate (50 mL), dried over sodium sulfate, filtered, and concentrated. Purification by flash column chromatography (10-80% ethyl acetate/heptanes) gave the title compound (863 mg, 59%) as a white solid. +APCI (M+H) 267.2; 1H NMR (400 MHz, CDCl3, δ): 12.63 (br. s., 1H), 8.13 (s, 1H), 4.34 (q, J=7.0 Hz, 2H), 1.38 (t, J=7.2 Hz, 3H).

1. dissolutionhad dissolved
2. stirringThe reaction was stirred at room temperature for 2 minutes when
3. stirringstirring
4. customto precipitate formation
5. additionAdditional water (5 mL) was added
6. stirringto stir overnight
7. customThe acetic acid was removed under reduced pressure
8. extractionwas extracted with ethyl acetate (2×50 mL)
9. washThe combined organics were washed with saturated aqueous sodium thiosulfate (50 mL)
10. dry with materialdried over sodium sulfate
11. filtrationfiltered
12. concentrationconcentrated
13. customPurification by flash column chromatography (10-80% ethyl acetate/heptanes)

ORD record

ord-6ef57fcfffdb4498a96ff7e65d82a7dc

Source dataset

uspto-grants-2014_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08859773B2