Reaktion #424899

Reaktionsgleichung

sodium hydrogencarbonate

cyclopentene oxide

1-methylpyrazole

n-butyl lithium

→

title compound

Ausbeute 21.3%

(1S*,2R*)-2-(1-Methyl-1H-pyrazol-5-yl)cyclopentanol

Ausbeute 21.3%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionfollowed by extraction with ethyl acetate (500 mL)
2. 2
   TrocknenThe thus obtained organic layer was dried over anhydrous sodium sulfate
3. 3
   EinengenAfter vacuum concentration
4. 4
   Sonstigethe residue was purified with silica gel chromatography (dichloromethane/methanol=97:3)

Vorschrift

To a solution of 1-methylpyrazole (13.4 g, 163 mmol) in THF (1 L), n-butyl lithium (1.63 M solution in hexane; 100 mL, 163 mmol) was added dropwise at −78° C. for 40 minutes. To the reaction solution, cyclopentene oxide (15.1 g, 179 mmol) was added at −78° C., and the reaction solution was stirred at room temperature for 20 hours. To the reaction solution, a saturated aqueous solution of sodium hydrogencarbonate (100 mL) was added, followed by extraction with ethyl acetate (500 mL). The thus obtained organic layer was dried over anhydrous sodium sulfate. After vacuum concentration, the residue was purified with silica gel chromatography (dichloromethane/methanol=97:3) to yield the title compound (5.77 g, 21%) as a colorless oil.

Quelle