Reaktion #78378

Reaktionsgleichung

water

methyl isobutyrylacetate

4-fluorobenzonitrile

tin tetrachloride

→

methyl 2-[1-amino-1-(4-fluorophenyl)-methylene]-4-methyl-3-oxopentanoate

Ausbeute 54.3%

Lösungsmittel

toluene

ethyl acetate

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITAfter 2.5 h
2. 2
   Temperaturthe suspension was again cooled to room temperature
3. 3
   Sonstigethe phases were separated
4. 4
   ExtraktionAfter extraction of the aqueous phase with ethyl acetate (2×5 ml)
5. 5
   Trocknenthe combined organic phases were dried over magnesium sulphate
6. 6
   EinengenAfter concentration in vacuo
7. 7
   Sonstige3.50 g of crude product were obtained in the form of a pale yellow, tacky solid
8. 8
   Sonstigepurified by flash chromatography (n-hexane/ethyl acetate 5:1 to 1:1)
9. 9
   EinengenAfter concentration in vacuo

Vorschrift

1.50 g of methyl isobutyrylacetate (10.0 mmol, concentration 96%) and 1.24 g of 4-fluorobenzonitrile (10 mmol, concentration 98%) were dissolved in 10 ml of toluene and treated with 2.63 g of tin tetrachloride (10 mmol, concentration 99%) at room temperature over the course of 6 min. After 3 h at room temperature, the mixture was heated to 80° C. After 2.5 h, the suspension was again cooled to room temperature and treated with 10 ml of water. It was diluted with 5 ml of ethyl acetate and the phases were separated. After extraction of the aqueous phase with ethyl acetate (2×5 ml), the combined organic phases were dried over magnesium sulphate. After concentration in vacuo, 3.50 g of crude product were obtained in the form of a pale yellow, tacky solid. The solid was dissolved in ethyl acetate and purified by flash chromatography (n-hexane/ethyl acetate 5:1 to 1:1). After concentration in vacuo, 1.44 g of methyl 2-[1-amino-1-(4-fluorophenyl)-methylene]-4-methyl-3-oxopentanoate were obtained.

Quelle