Acetic Acid → 6-Bromopyrazolo[1,5-a]pyrimidine-3-carboxylic acid

Temperature

70 °C

A solution of ethyl 5-amino-1H-pyrazole-4-carboxylate (2 g, 12.89 mmol) and sodium hydroxide (19.34 mL, 38.7 mmol) (aqueous, 2M) in ethanol (30 mL) was heated at 80° C. overnight. The reaction mixture was concentrated in vacuo to give a crude mixture of carboxylate and sodium hydroxide. The crude mixture was dissolved in ethanol (4 mL) and acetic acid (14 mL, 245 mmol). Whilst stirring the mixture, bromomalonaldehyde (1.947 g, 12.90 mmol) was added and then the mixture heated to 70° C. for 1 h. The reaction mixture was allowed to cool and the precipitate was filtered and washed with ethanol. The solid product was dried in a vacuum oven to give the title compound (1.589 g).

1. concentrationThe reaction mixture was concentrated in vacuo
2. customto give a crude
3. additionwas added
4. temperatureto cool
5. filtrationthe precipitate was filtered
6. washwashed with ethanol
7. customThe solid product was dried in a vacuum oven

ORD record

ord-5249bd5d12a84c86b40b10be0ee46e27

Source dataset

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08093249B2