Reaktion #9631

Reaktionsgleichung

methyl 4-(2-chloro-2-oxoethyl)tetrahydro-2H-pyran-4-carboxylate

bromobenzene

aluminum chloride

→

methyl 4-[2-(4-bromo-phenyl)-2-oxoethyl]tetrahydro-2H-pyran-4-carboxylate

Ausbeute 55.0%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe ice-water bath was removed
2. 2
   TemperaturThe mixture was then cooled at 0° C.
3. 3
   Sonstigequenched by the addition of 1 N HCl solution and water
4. 4
   ExtraktionThe mixture was extracted with dichloromethane
5. 5
   Trocknenthe combined organic phases were dried over sodium sulfate
6. 6
   SonstigeThe crude material was then purified by flash chromatography (Biotage Flash 40 M, 2:1 hexane/ethyl acetate

Vorschrift

To a solution of methyl 4-(2-chloro-2-oxoethyl)tetrahydro-2H-pyran-4-carboxylate (1.06 g, 4.8 mmol) and bromobenzene (1.13 g, 7.21 mmol) in dichloromethane (20 mL) at 0° C. was added aluminum chloride (1.92 g, 14.4 mmol). The ice-water bath was removed and the reaction mixture was stirred at rt for 16 h. The mixture was then cooled at 0° C. and quenched by the addition of 1 N HCl solution and water. The mixture was extracted with dichloromethane, and the combined organic phases were dried over sodium sulfate. The crude material was then purified by flash chromatography (Biotage Flash 40 M, 2:1 hexane/ethyl acetate, to afford methyl 4-[2-(4-bromo-phenyl)-2-oxoethyl]tetrahydro-2H-pyran-4-carboxylate (900 mg, 55%). LC-MS ret. time 2.76 min; m/z 342.9 (MH+); 1H NMR (300 MHz, CDCl3) δ 1.58–1.69 (m, 2H), 2.12–2.18 (m, 2H), 3.28 (s, 2H), 3.64 (s, 3H), 3.69–3.77 (m, 4H), 7.59 (d, 2H), 7.77 (d, 2H).

Quelle