Potassium Carbonate → HCID 178419375, compound

Participants

Reaction Steps

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%).

Provenance & Evidence