Reaktion #445195

Reaktionsgleichung

ammonia

3,4-dihydro-3,3,5-trimethoxy-4-chloro-2(5H)-furanone

HCl

ammonia

→

3,3,5-trimethoxy-4-chloro-2-pyrrolidinone

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISTILLATIONfollowed by distillation under reduced pressure
2. 2
   ExtraktionThe residue was extracted with chloroform
3. 3
   workup.DISTILLATIONthe chloroform was distilled off
4. 4
   workup.DISSOLUTIONthe residual oil was dissolved in methanol-HCl-saturated methanol (20 ml)
5. 5
   Temperaturrefluxed for 1 hour
6. 6
   EinengenThe reaction mixture was concentrated under reduced pressure
7. 7
   Einengenconcentrated under reduced pressure
8. 8
   Sonstigeto give crystals
9. 9
   SonstigeRecrystallization from benzene

Vorschrift

Concentrated aqueous ammonia (10 ml) was cooled to -10° C. and 3,4-dihydro-3,3,5-trimethoxy-4-chloro-2(5H)-furanone (2 g) was gradually added. The mixture was stirred at 0° C. for about 5 minutes, at the end of which time the excess ammonia was neutralized with HCl-saturated methanol, followed by distillation under reduced pressure. The residue was extracted with chloroform, the chloroform was distilled off, and the residual oil was dissolved in methanol-HCl-saturated methanol (20 ml) and refluxed for 1 hour. The reaction mixture was concentrated under reduced pressure and the residue was subjected to silica gel column chromatography using hexane-acetone (5:3) as the eluent. The active fractions were pooled and concentrated under reduced pressure to give crystals. Recrystallization from benzene yielded 3,3,5-trimethoxy-4-chloro-2-pyrrolidinone as crystals (1.12 g).

Quelle