Potassium Carbonate → HCID 178419375, compound

A suspension of 1-acetyl-3-hydroxy-pyrazole (1.0 g, 7.9 mmol), 2-bromobenzyl bromide (2.0 g, 7.9 mmol) and K2CO3 (1.2 g, 8.4 mmol) in 20 mL of 2-butanone was heated to reflux for 90 min. After cooling to room temperature, the precipitated salts were filtered off and rinsed with tert-butyl methyl ether (TBME). The filtrate was then concentrated under reduced pressure (50 mbar) and redissolved in a mixture of tetrahydrofuran (THF) and methanol (MeOH) (3:2, 25 mL). 1 mL of a 10% NaOH solution was added and the solution was stirred 60 min at ambient temperature. Then, all volatiles were removed under reduced pressure (50 mL). The residue was diluted with 10 mL of H2O and 20 mL of ethyl acetate (EtOAc). The aqueous phase was extracted with EtOAc (2×10 mL). The combined organic layers were washed with water and brine (both 20 mL) and dried over Na2SO4. The crude product was obtained after evaporation of all volatiles and used in the next step without further purification (1.9 g, 7.5 mmol, 95%).

1. temperaturewas heated
2. temperatureto reflux for 90 min
3. filtrationthe precipitated salts were filtered off
4. washrinsed with tert-butyl methyl ether (TBME)
5. concentrationThe filtrate was then concentrated under reduced pressure (50 mbar)
6. dissolutionredissolved in a mixture of tetrahydrofuran (THF) and methanol (MeOH) (3:2, 25 mL)
7. addition1 mL of a 10% NaOH solution was added
8. customThen, all volatiles were removed under reduced pressure (50 mL)
9. additionThe residue was diluted with 10 mL of H2O and 20 mL of ethyl acetate (EtOAc)
10. extractionThe aqueous phase was extracted with EtOAc (2×10 mL)
11. washThe combined organic layers were washed with water and brine (both 20 mL) and
12. dry with materialdried over Na2SO4

ORD record

ord-10fe0c12567e44fa80c8eeaad4330520

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08362271B2