Reaktion #70236

Reaktionsgleichung

O-(3-fluorobenzyl)hydroxylamine hydrochloride

3-fluoro-4-methoxyacetophenone

pyridine

→

3′-fluoro-4′-methoxyacetophenone-O-3-fluorobenzyloxime

Ausbeute 90.1%

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturat reflux under nitrogen for 4 h
2. 2
   EinengenThe solution was concentrated to a pale yellow oil which
3. 3
   workup.ADDITIONwas diluted with water
4. 4
   ExtraktionThe suspension was extracted with dichloromethane (×3)
5. 5
   WaschenThe combined organic phases were washed with water and brine
6. 6
   Trocknendried over magnesium sulphate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated to a white solid
9. 9
   SonstigeThe crude product was purified by column chromatography (SiO2)
10. 10
    Wascheneluting with 95:5 petrol/ethyl acetate

Vorschrift

A solution of 3-fluoro-4-methoxyacetophenone (0.063 g, 0.377 mmol), O-(3-fluorobenzyl)hydroxylamine hydrochloride (0.100 g, 0.569 mmol) and pyridine (0.14 ml, 1.73 mmol) in ethanol (5 ml) was stirred at reflux under nitrogen for 4 h and cooled to room temperature. The solution was concentrated to a pale yellow oil which was diluted with water. The suspension was extracted with dichloromethane (×3). The combined organic phases were washed with water and brine, dried over magnesium sulphate, filtered and concentrated to a white solid. The crude product was purified by column chromatography (SiO2), eluting with 95:5 petrol/ethyl acetate, to give 3′-fluoro-4′-methoxyacetophenone-O-3-fluorobenzyloxime (CP9-126) as a white solid (0.099 g, 90%), m.p. 67°.

Quelle