Reaktion #9278

Reaktionsgleichung

7-bromo-2-ethylpyrazolo[1,5-a]pyridine

2,4-dichlorophenylboric acid

sodium carbonate

Water

→

title compound

Ausbeute 97.9%

7-(2,4-Dichlorophenyl)-2-ethylpyrazolo[1,5-a]pyridine

Ausbeute 97.9%

Lösungsmittel

ethanol

toluene

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added
2. 2
   Temperaturthe mixture was heated
3. 3
   Waschenthe organic layer was washed with brine
4. 4
   TrocknenAfter drying over anhydrous magnesium sulfate and filtration
5. 5
   Einengenthe solvent was concentrated under reduced pressure
6. 6
   Sonstigethe residue was purified by silica gel column chromatography

Vorschrift

After dissolving 7-bromo-2-ethylpyrazolo[1,5-a]pyridine (300 mg) in ethanol (2 mL) and toluene (4 mL), 2,4-dichlorophenylboric acid (508 mg), tetrakis(triphenylphosphine)palladium (0) complex (154 mg) and 2 M aqueous sodium carbonate (1.33 mL) were added and the mixture was heated and stirred at 80° C. for 3 hours under a nitrogen stream. Water was added to the reaction mixture, extraction was performed with ethyl acetate and the organic layer was washed with brine. After drying over anhydrous magnesium sulfate and filtration, the solvent was concentrated under reduced pressure, the residue was purified by silica gel column chromatography, and the title compound (380 mg) was obtained from the n-hexane:ethyl acetate (100:1) fraction as a light yellow oil.

Quelle