Reaktion #936409

Reaktionsgleichung

3,4-dimethoxyacetophenone

hydrochloric acid

tetrahydrofuran

samarium(II) iodide

oxygen

tetrahydrofuran

methyl acrylate

→

5-(3,4-Dimethoxyphenyl)-5-methyl-dihydro-2-furanone

Lösungsmittel

tert-butanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONThe reaction solution is mixed thoroughly
2. 2
   Extraktionextracted with diethyl ether
3. 3
   WaschenThe ether phase is washed with sodium thiosulfate solution and water
4. 4
   Sonstigedried on sodium sulfate
5. 5
   Einengenconcentrated by evaporation in a vacuum
6. 6
   SonstigeThe oily residue is chromatographed on a silica gel column (Kromasil 100/10 μm) with a hexane-tert-butyl methyl ether mixture (4:1)
7. 7
   Waschen570 mg of (R,S)-5-(3,4-dimethoxyphenyl)-5-methyl-dihydro-2-furanone is eluted

Vorschrift

100 ml of a 0.1 M solution of samarium(II) iodide in tetrahydrofuran is mixed, with oxygen carefully excluded, with the solution of 710 mg of 3,4-dimethoxyacetophenone, 500 mg of methyl acrylate and 350 mg of tert-butanol in 5 ml of tetrahydrofuran. The reaction solution is mixed thoroughly, allowed to stand for two hours at room temperature and then poured into 100 ml of 20% hydrochloric acid. It is stirred for two hours at room temperature and extracted with diethyl ether. The ether phase is washed with sodium thiosulfate solution and water, dried on sodium sulfate and concentrated by evaporation in a vacuum. The oily residue is chromatographed on a silica gel column (Kromasil 100/10 μm) with a hexane-tert-butyl methyl ether mixture (4:1). 570 mg of (R,S)-5-(3,4-dimethoxyphenyl)-5-methyl-dihydro-2-furanone is eluted, melting point 71.2° C.

Quelle