Reaktion #2295091

Reaktionsgleichung

[5-(5-Bromo-thiophen-2-yl)-1-(2,4-difluoro-phenyl)-4,5-dihydro-1H-pyrazol-3-yl]-methanol

[5-(5-bromo-thiophen-2-yl)-1-(2,4-difluoro-phenyl)-4,5-dihydro-1H-pyrazol-3-yl]-methanol

magnesium dioxide

→

titled compound

Ausbeute 71.1%

5-(5-bromo-thiophen-2-yl)-1-(2,4-difluoro-phenyl)-4,5-dihydro-1H-pyrazole-3-carbaldehyde

Ausbeute 71.1%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Filtrationfiltered
2. 2
   Sonstigeto obtain a yellow filtrate
3. 3
   EinengenThe filtrate was concentrated under reduced pressure
4. 4
   SonstigeThe resulting residue was purified by silica gel column chromatography (eluent: n-hexane)

Vorschrift

[5-(5-Bromo-thiophen-2-yl)-1-(2,4-difluoro-phenyl)-4,5-dihydro-1H-pyrazol-3-yl]-methanol (12.9 g, 34.5 mmol) prepared in Step 4 and magnesium dioxide (MnO2) (30.0 g, 344.6 mmol) were added to dichloromethane (115.0 mL). The reaction mixture was stirred at room temperature for 3 days and then filtered to obtain a yellow filtrate. The filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: n-hexane) to give 9.1 g of the titled compound as a yellow liquid.

Quelle