Reaktion #78381

Reaktionsgleichung

water

methyl isobutyrylacetate

4-fluorobenzonitrile

tin tetrachloride

→

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

Ausbeute 60.7%

Lösungsmittel

toluene

dichloroethane

n-hexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITAfter half an hour at room temperature
2. 2
   Temperaturthe suspension was cooled to 10° C.
3. 3
   Sonstigethe phases were separated
4. 4
   WaschenThe organic phase was washed with 2×100 ml of 1N sodium hydroxide solution
5. 5
   EinengenAfter concentration in vacuo
6. 6
   Sonstige125.5 g of crude product were obtained in the form of a yellowish solid
7. 7
   Temperaturunder reflux
8. 8
   Filtrationfiltered hot
9. 9
   SonstigeThe product precipitated from the filtrate
10. 10
    Temperaturon cooling
11. 11
    FiltrationBy filtering through a frit
12. 12
    Waschenwashing the filter cake with 130 ml of n-hexane

Vorschrift

75.09 g of methyl isobutyrylacetate (0.50 mol, concentration 96%) and 61.8 g of 4-fluorobenzonitrile (0.50 mol, concentration 98%) were dissolved in 500 ml of toluene and treated with 144.72 g of tin tetrachloride (0.55 mol, concentration 99%) at room temperature over the course of 15 min. After half an hour at room temperature, the mixture was heated to 80° C. After 3 h, the suspension was cooled to 10° C. and treated with 500 ml of water. The mixture was diluted with 100 ml of dichloroethane and the phases were separated. The organic phase was washed with 2×100 ml of 1N sodium hydroxide solution. After concentration in vacuo, 125.5 g of crude product were obtained in the form of a yellowish solid. The solid was dissolved in 160 ml of n-hexane under reflux and filtered hot. The product precipitated from the filtrate on cooling. By filtering through a frit and washing the filter cake with 130 ml of n-hexane, 79.8 g of methyl 2-[1-amino-1-(4-fluorophenyl)methylene]-4-methyl-3-oxopentanoate were obtained in the form of a spectroscopically pure solid.

Quelle