Reaktion #8585

Reaktionsgleichung

sodium hydroxide

2-(6-chloro-2-pyridinyl)-1-(4-fluorophenyl)ethanone

hydroxylamine hydrochloride

→

2-(6-chloro-2-pyridinyl)-1-(4-fluorophenyl)ethanone oxime

Ausbeute 86.0%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto reflux for 2 hours
2. 2
   EinengenThe mixture was concentrated in vacuo
3. 3
   WaschenThe organic layer was washed with brine
4. 4
   ExtraktionThe aqueous layer was extracted with ether
5. 5
   Trocknenthe combined organics were dried over magnesium sulfate
6. 6
   FiltrationFiltration and concentration
7. 7
   Sonstigegave a solid residue which
8. 8
   Sonstigewas purified by recrystallization from ethyl acetate-hexanes

Vorschrift

To a solution of 2-(6-chloro-2-pyridinyl)-1-(4-fluorophenyl)ethanone (74.9 g, 299.8 mmol) in methanol (900 mL) was added hydroxylamine hydrochloride (104 g, 1.49 mol) followed by sodium hydroxide (600 mL, 10% aqueous, 1.5. mol). The resultant suspension was heated to reflux for 2 hours and then cooled to room temperature. The mixture was concentrated in vacuo and the residue taken up in ether and water. The organic layer was washed with brine. The aqueous layer was extracted with ether and the combined organics were dried over magnesium sulfate. Filtration and concentration gave a solid residue which was purified by recrystallization from ethyl acetate-hexanes to provide 2-(6-chloro-2-pyridinyl)-1-(4-fluorophenyl)ethanone oxime (67.9 g, 86%) as a white solid. 1H NMR (CDCl3): δ 8.69 (s, 1 H), 7.71 (dd, 2 H), 7.53 (t, 1 H), 7.18–7.16 (m, 2 H), 7.03 (t, 2 H), 4.37 (s, 2 H); 19F NMR (CDCl3) δ −111.77; MS m/z 265 (M+1).

Quelle