Reaktion #8296

Reaktionsgleichung

borontrifluoride etherate

4-(5-methoxy-tetrahydro-furan-3-yl)-benzoic acid ethyl ester

3-chloroperbenzoic acid

magnesium sulfate

→

title compound

4-(5-Oxo-tetrahydro-furan-3-yl)-benzoic acid ethyl ester

Lösungsmittel

ether

dichloromethane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeSolids are removed by filtration
2. 2
   workup.STIRRINGThe mixture is stirred at room temperature 18 h
3. 3
   Waschenwashed with a 10% solution of sodium thiosulfite (150 mL)
4. 4
   TrocknenThe mixture is dried over magnesium sulfate
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated in vacuo
7. 7
   SonstigeThe residue is chromatographed on SiO2 (elute with 20% ethyl acetate/hexanes)

Vorschrift

To a solution of 75% 3-chloroperbenzoic acid (2.7 g, 11.76 mmol) in dichloromethane (35 mL) is added magnesium sulfate (2.0 g, 16.6 mmol) and the mixture stirred for 30 min. Solids are removed by filtration and the filtrate treated with borontrifluoride etherate (0.5 mL, 3.92 mmol) and 4-(5-methoxy-tetrahydro-furan-3-yl)-benzoic acid ethyl ester (2.45 g, 9.8 mmol) in dichloromethane (5 mL). The mixture is stirred at room temperature 18 h, diluted with ether (200 mL) and washed with a 10% solution of sodium thiosulfite (150 mL), a saturated solution of sodium bicarbonate (150 mL) and brine. The mixture is dried over magnesium sulfate, filtered and concentrated in vacuo. The residue is chromatographed on SiO2 (elute with 20% ethyl acetate/hexanes) to yield the title compound, 2.2 g (96%), as an off-white solid.

Quelle