Reaktion #429357

Reaktionsgleichung

Magnesium

bromoethane

1-bromo-2-(2-tetrahydropyranyloxymethyl)benzene

diethyl oxalate

→

ethyl 2-oxo-2-[2-(2-tetrahydropyranyloxymethyl)phenyl]acetate

Ausbeute 77.3%

Lösungsmittel

water

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled to -78° C
2. 2
   workup.STIRRINGThe mixture was stirred at -78° C. for 1 hour
3. 3
   Extraktionthe mixture was extracted with ether (200 ml)
4. 4
   TrocknenThe extract was dried over anhydrous magnesium sulfate
5. 5
   Einengenconcentrated under reduced pressure
6. 6
   SonstigeThe resulting residue was purified by silica gel chromatography (ethyl acetate/n-hexane)

Vorschrift

Magnesium (2.67 g, 0.11 mol) and bromoethane (0.2 ml) were added to a mixed solution of 1-bromo-2-(2-tetrahydropyranyloxymethyl)benzene (27.11 g, 0.10 mol) and THF (50 ml) under an atmosphere of nitrogen gas. The mixture was stirred at room temperature for 1 hour to prepare a Grignard reagent. The Grignard reagent was added dropwise to a mixed solution of diethyl oxalate (29.23 g, 0.20 mol) and THF (100 ml) cooled to -78° C. The mixture was stirred at -78° C. for 1 hour, water (150 ml) was added, and the mixture was extracted with ether (200 ml). The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified by silica gel chromatography (ethyl acetate/n-hexane) to obtain ethyl 2-oxo-2-[2-(2-tetrahydropyranyloxymethyl)phenyl]acetate (22.60 g, Yield: 77.3%) as a colorless oil.

Quelle