Réaction #657313

Équation de réaction

1-{[3-(4-fluorophenyl)-1H-pyrazol-5-yl]oxy}acetone

acetic acid

p-TsOH

→

6-(4-fluorophenyl)-3-methylpyrazolo[5,1-b][1,3]oxazole

Rendement 46.3%

Solvants

toluene

EtOAc

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONwas charged at RT
2. 2
   Lavagewashed with brine
3. 3
   SéchageThe organic layer dried over sodium sulphate
4. 4
   Concentrationconcentrated under reduced pressure
5. 5
   Autreto get the crude which
6. 6
   Autrewas then purified by column chromatography 100-200 mesh)
7. 7
   Lavageeluted with 5-10% ethyl acetate in hexane as eluent

Mode opératoire

To a stirred solution of 1-{[3-(4-fluorophenyl)-1H-pyrazol-5-yl]oxy}acetone (0.25 g, 1.0 mmol) in toluene, equipped with dean stark apparatus, acetic acid (2 ml) and p-TsOH (25 mg, cat.) was charged at RT and the reaction mass was refluxed at 130° C. for 16 h. After completion, the reaction was diluted with EtOAc (50 ml) and washed with brine. The organic layer dried over sodium sulphate and concentrated under reduced pressure to get the crude which was then purified by column chromatography 100-200 mesh) eluted with 5-10% ethyl acetate in hexane as eluent to get compound 6-(4-fluorophenyl)-3-methylpyrazolo[5,1-b][1,3]oxazole (0.1 g, yield 43%).

Source