Reaktion #5274

Reaktionsgleichung

ethyl 3-amino-2-(4-chlorophenyl)propyl(diethoxymethyl)phosphinate

→

3-amino-2-(4-chlorophenyl)propylphosphonous acid

Lösungsmittel

hydrochloric acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto reflux for a period of 1 h
2. 2
   Einengenconcentrated under reduced pressure
3. 3
   workup.DISSOLUTIONThe crude product is dissolved in 20 ml of water
4. 4
   Waschenwashed twice with 20 ml of diethyl ether
5. 5
   Sonstigethe aqueous layer is then separated
6. 6
   Sonstigeevaporated under reduced pressure
7. 7
   workup.DISSOLUTIONThe crude product is dissolved in 50 ml ethanol
8. 8
   workup.ADDITION5 ml of propylene oxide is added dropwise
9. 9
   FiltrationThe precipitated solid is collected by filtration
10. 10
    Sonstigedried

Vorschrift

A solution of 5.0 g of ethyl 3-amino-2-(4-chlorophenyl)propyl(diethoxymethyl)phosphinate in 60 ml of 36% aqueous hydrochloric acid is heated to reflux for a period of 1 h. The reaction mixture is then allowed to cool to room temperature, concentrated under reduced pressure and co-evaporated twice with 20 ml of water under reduced pressure. The crude product is dissolved in 20 ml of water, washed twice with 20 ml of diethyl ether and the aqueous layer is then separated and evaporated under reduced pressure. The crude product is dissolved in 50 ml ethanol and 5 ml of propylene oxide is added dropwise. The precipitated solid is collected by filtration and dried to give 3-amino-2-(4-chlorophenyl)propylphosphonous acid (1/3M H2O), m.p. 235°-240° C., 31P=+23.9 ppm (D2O).

Quelle