Reaktion #9287

Reaktionsgleichung

4,6-dimethyl-2-methoxyphenylboric acid

barium hydroxide octahydrate

7-bromo-2-ethyl-4-methoxy-3-nitropyrazolo[1,5-a]pyridine

→

title compound

Ausbeute 98.3%

2-Ethyl-4-methoxy-7-(2-methoxy-4,6-dimethylphenyl)-3-nitropyrazolo[1,5-a]pyridine

Ausbeute 98.3%

Lösungsmittel

Water

ethyleneglycol diethyl ether

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextraction
2. 2
   Waschenthe extract was washed with saturated aqueous sodium hydrogencarbonate and brine
3. 3
   Trocknendried over magnesium sulfate
4. 4
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure

Vorschrift

After adding 4,6-dimethyl-2-methoxyphenylboric acid (191 mg), barium hydroxide octahydrate (334 mg) and tetrakis(triphenylphosphine)palladium (0) complex (123 mg) to a solution of 7-bromo-2-ethyl-4-methoxy-3-nitropyrazolo[1,5-a]pyridine (159 mg) in a mixture of ethyleneglycol diethyl ether (15 mL) and water (7.5 mL), the mixture was heated at 80° C. for 30 minutes. Water was added, extraction was performed with ethyl acetate, the extract was washed with saturated aqueous sodium hydrogencarbonate and brine and dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was subjected to silica gel column chromatography (20 g), and the title compound (185 mg) was obtained from the n-hexane:ethyl acetate (5:1) fraction as yellow crystals.

Quelle