Reaktion #94447

Reaktionsgleichung

1-phenyl-2-(2-piperidinylidene)-1,3-butanedione

sodium

acetic acid

→

2-(2-piperidinylidene)-acetophenone

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture is then refluxed for 40 minutes
2. 2
   TemperaturAfter cooling
3. 3
   Filtrationfiltered off from the sodium acetate
4. 4
   EinengenThe filtrate is concentrated in the rotary evaporator
5. 5
   workup.DISSOLUTIONthe residue is dissolved in methylene chloride
6. 6
   ExtraktionThe solution is repeatedly extracted with water
7. 7
   Trocknenthe organic phase is dried over sodium sulphate
8. 8
   Sonstigethe solvent is evaporated off in the rotary evaporator
9. 9
   SonstigeThe oily residue is crystallised from ether/hexane

Vorschrift

12.15 g (0.05 mole) of 1-phenyl-2-(2-piperidinylidene)-1,3-butanedione are introduced into a prepared solution of 3.5 g of sodium in 120 ml of ethanol. The reaction mixture is then refluxed for 40 minutes. After cooling, it is neutralised with glacial acetic acid, and filtered off from the sodium acetate. The filtrate is concentrated in the rotary evaporator, and the residue is dissolved in methylene chloride. The solution is repeatedly extracted with water; the organic phase is dried over sodium sulphate, and the solvent is evaporated off in the rotary evaporator. The oily residue is crystallised from ether/hexane to yield 2-(2-piperidinylidene)-acetophenone, m.p. 59°-60°.

Quelle