Reaktion #57542

Reaktionsgleichung

1-(2-Bromo-4-fluoro-phenyl)-ethanone

phenyltrimethylammonium tribromide

→

2-bromo-1-(2-bromo-4-fluoro-phenyl)-ethanone

Ausbeute 63.0%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Einengenconcentrated
2. 2
   workup.DISSOLUTIONre-dissolved in ethyl acetate
3. 3
   WaschenThe organic layer was washed with water (2×150 mL) and brine (1×100 mL)
4. 4
   Trocknendried (MgSO4)
5. 5
   Filtrationfiltered
6. 6
   Sonstigeevaporated in vacuo
7. 7
   SonstigePurification

Vorschrift

To 1-(2-Bromo-4-fluoro-phenyl)-ethanone (2.5 g, 11.52 mmol) in anhydrous tetrahydrofuran (53 mL) under argon was added phenyltrimethylammonium tribromide (4.33 g, 11.52 mmol, 1.0 eq) at 0° C. The reaction mixture was stirred at ambient temperature for 16 h, concentrated, and re-dissolved in ethyl acetate. The organic layer was washed with water (2×150 mL) and brine (1×100 mL), dried (MgSO4), filtered, and evaporated in vacuo. Purification using MPLC chromatography (Biotage) gave 2.14 g (63%) of 2-bromo-1-(2-bromo-4-fluoro-phenyl)-ethanone as a clear oil. 1H-NMR (CD2Cl2) δ 7.57 (dd, J=9.6 Hz, 1H), 7.44 (dd, J=8, 2 Hz, 1H), 7.21 (m, 7.21-7.14, 1H), 4.51 (s, 2H); TLC Rf=0.38, 15% ethyl acetate-hexanes.

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