Reaktion #75914

Reaktionsgleichung

6-methoxy-2-methylindanone

benzene

iodine

benzene

ethyl bromoacetate

→

ethyl-(1-hydroxy-2-methyl-6-methoxy-indenyl) acetate

Lösungsmittel

ethanol

acetic acid

ether

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe reaction
2. 2
   Temperaturthe reaction mixture is maintained
3. 3
   Temperaturat reflux temperature (ca. 65°) with external heating
4. 4
   workup.WAITAt three-hour intervals, two batches of 10 g
5. 5
   Temperaturthe mixture is then refluxed for 8 hours
6. 6
   workup.ADDITIONAfter addition of 30 ml
7. 7
   SonstigeThe organic layer is separated
8. 8
   Extraktionthe aqueous layer is extracted twice with ether
9. 9
   WaschenThe combined organic layers are washed thoroughly with water, ammonium hydroxide and water
10. 10
    TrocknenDrying over sodium sulfate, evaporation of solvent in vacuo
11. 11
    Sonstigeby pumping at 80°

Vorschrift

A solution of 13.4 g of 6-methoxy-2-methylindanone and 21 g. of ethyl bromoacetate in 45 ml. benzene is added over a period of five minutes to 21 g. of zinc amalgam (prepared according to Org. Syn. Coll. Vol. 3) in 110 ml. benzene and 40 ml. dry ether. A few cyrstals of iodine are added to start the reaction, and the reaction mixture is maintained at reflux temperature (ca. 65°) with external heating. At three-hour intervals, two batches of 10 g. zinc amalgam and 10 g. bromoester are added and the mixture is then refluxed for 8 hours. After addition of 30 ml. of ethanol and 150 ml. of acetic acid, the mixture is poured into 700 ml. of 50% aqueous acetic acid. The organic layer is separated, and the aqueous layer is extracted twice with ether. The combined organic layers are washed thoroughly with water, ammonium hydroxide and water. Drying over sodium sulfate, evaporation of solvent in vacuo followed by pumping at 80° (bath temperature)(1-2 mm.) gives crude ethyl-(1-hydroxy-2-methyl-6-methoxy-indenyl) acetate (ca. 18 g.).

Quelle