Reaktion #713959

Reaktionsgleichung

Phosphorus(V) oxybromide

2-(2,6-dichlorophenyl)-7-methyl-2H-pyrazolo[4,3-c]pyridine-5-oxide

sodium carbonate

→

title compound

Ausbeute 38.0%

4-Bromo-2-(2,6-dichlorophenyl)-7-methyl-2H-pyrazolo[4,3-c]pyridine

Ausbeute 38.0%

Lösungsmittel

DCE

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat room temperature
2. 2
   Sonstigeovernight
3. 3
   workup.STIRRINGwas stirred for 10 minutes
4. 4
   ExtraktionThis was extracted with DCM
5. 5
   Waschenthe organic layer was washed with brine
6. 6
   Trocknendried over anhydrous magnesium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated under reduced pressure
9. 9
   SonstigeThe residue was purified by silica gel flash chromatography (0-30% ethyl acetate in cyclohexane)

Vorschrift

Phosphorus(V) oxybromide (921 mg, 3.43 mmol) was slowly added to a suspension of 2-(2,6-dichlorophenyl)-7-methyl-2H-pyrazolo[4,3-c]pyridine-5-oxide (404 mg, 1.37 mmol) in DCE (9.0 mL) at 0° C., under an atmosphere of nitrogen. The reaction mixture was stirred at 0° C. for 30 minutes and then at room temperature overnight. The orange suspension was poured onto saturated aqueous sodium carbonate solution and was stirred for 10 minutes. This was extracted with DCM and the organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel flash chromatography (0-30% ethyl acetate in cyclohexane) to afford the title compound as a white solid (185 mg, 38% yield). 1H NMR (300 MHz, DMSO-d6): δ 9.20 (s, 1H), 7.90-7.89 (m, 1H), 7.84-7.80 (m, 2H), 7.76-7.72 (m, 1H), 2.45 (d, J=1.2 Hz, 3H).

Quelle