Diethyl Malonate → HCID 178516615, compound

Temperature

80 °C

To 1H-pyrazol-3-amine (12.3 g, 148.0 mmol) in EtOH (50 mL) was added diethyl malonate (25.0 mL, 164.7 mmol), 21 wt % NaOEt in EtOH (110 mL, 294.6 mmol) and additional EtOH (50 mL). The resulting mixture was then heated at 80° C. under an atmosphere of argon for 16 hours, at which time the reaction was allowed to cool to room temperature. The reaction mixture was then concentrated in vacuo until almost dry, before H2O (500 mL) was added. Vigorous stirring aided the dissolving of solids, at which time conc. HCl was added until pH˜2 was attained (solid precipitate formed). The precipitate was collected and dried by vacuum filtration giving pyrazolo[1,5-a]pyrimidine-5,7-diol as a tan solid (17.13 g, 113.4 mmol, 77%).

1. temperatureto cool to room temperature
2. concentrationThe reaction mixture was then concentrated in vacuo
3. dry with materialuntil almost dry, before H2O (500 mL)
4. additionwas added
5. dissolutiondissolving of solids, at which time conc. HCl
6. additionwas added until pH˜2
7. custom(solid precipitate formed)
8. customThe precipitate was collected
9. customdried by vacuum filtration

ORD record

ord-917eec15830f4aa6bcbcc1c9886141d3

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08703784B2